"The future foretold, the past explained, the present...apologised for.”
Doctor Who. BBC TV (1979)
Doctor Who. BBC TV (1979)
Paleogeography in Exploration: Lessons from the Past for the Next Generation of Explorers
Paleogeography in Exploration: Lessons from the Past for the Next Generation of Explorers
The original version of this article was published in the August 2020 issue of AAPG Explorer. This copy includes reference citations.
There is something about colored pencil crayons that we, as geologists, find impossible to resist. From geological maps to field sketches, to interpreting seismic on those never-ending rolls of paper taped to the longest corridor wall we can find. What more could any geologist want?
This is a source of much mirth amongst my non-geological friends and concern amongst management especially those having just purchased the latest expensive software.
Our need for powerful software, paper, and colored pencils reflects a fundamental problem in geology and especially exploration: how to manage, analyze and visualize the diversity and wealth of information required to solve exploration problems.
Figure 1. The nature of the problem: There is so much to take in. The view from the Castillo de Samitier north towards Ainsa.
There is simply so much to take in.
I am reminded of this each spring when Douglas Paton and I take the Leeds MSc Structural Geology with Geophysics students out to the central Pyrenees. This is an area familiar to many of you and highly recommended to those of you yet to visit.
As we look out from the Castillo de Samitier with the students, geological notebooks in hand, the challenge is always the same: how far should we, can we, 'stray' away from teaching only the structural geology?
If we only focus on the structures, we miss drawing student attention to the important interactions between deformation and the evolution of the turbidite transport pathways; something they will need to know if they ever look at deep-water West Africa or Equatorial South America. To fully understand those pathways requires knowledge of hinterland evolution and the whole source-to-sink story, a story that is heavily dictated by not only tectonic uplift, landscape dynamics, and drainage network evolution, but vegetation cover, bedrock and climate and how these impact weathering and erosion. When we talk about the contemporary climate, what climate? The 'background', 'average' (whatever that means) climate? Or a really 'bad day' in the Eocene? - the Castissent flood events of (Marzo, Nijman and Puigdefabregas, 1988; Mutti et al., 2000), and what does that do to submarine-channel architecture downstream and the interconnectivity, porosity, and permeability of potential reservoirs?...
...and suddenly we find ourselves discussing regional paleogeography, Earth System modeling, the PETM (Paleocene Eocene Thermal Maximum), the importance of extreme events, ala Derek Ager's catastrophic uniformitarianism (Ager, 1984; Ager, 1993) and plate tectonics, and we have lost most of the day and possibly our audience...
There is simply so much to take in.
So, what do we do?
Focus just on the structures? That is the MSc course title after all.
Or do we bring in the other parts of the story - the bigger picture?
The answer is, of course, the latter, and the reason is obvious.
To solve geological problems in exploration we need to consider all the components.
Explorationists, and therefore our students, need to know enough of the vocabulary of each part of the Earth system to know what questions to ask, where to look for answers, and how the components fit together to dictate source rock geometry and character, trap formation and timing, reservoir quality and all the other plethora of geological risks they will need to assess as explorationists.
Paleogeography as a solution
This is not a new problem. 200 years ago, the early geologists were faced with the same challenge, how to manage, analyze and visualize the rapidly expanding observations accumulating in the databases of the time – the world’s libraries and museums.
One solution was to map out (in color of course) the accumulated knowledge on reconstructions of the past distribution of land and sea such as those of Elie de Beaumont in France and Charles Lyell in Britain (Lyell, 1837). For the first time here were representations of what the Earth looked like in the geological past. But by the 1870s it was clear that more was needed, especially following the Pennsylvanian (1859) and Ontario (1858) discoveries and the birth of oil exploration (Sorenson, 2007).
Figure 2. Charles Lyell’s 1837 land-sea map of the Tertiary of NW Europe
It was one of the first petroleum geologists, Thomas Sterry Hunt, who saw the value of paleogeography in exploration, and who, in 1873, first coined the term 'paleogeography’ (Hunt, 1873). Hunt had worked in the Ontario discoveries (Hunt, 1862) and was one of several geologists who had simultaneously recognized the importance of anticlinal traps. It is probably this structural experience that led Hunt to realize that in order to reconstruct paleogeography (past landscapes) you first need to understand the underlying “architecture of the Earth”, the crustal architecture on which the landscapes are formed.
Despite the obvious benefits of mapping structural evolution and depositional systems spatially in geological time, Hunt's ideas were not immediately utilized. It is true, that over the following three decades there were a large number of paleogeographic maps drawn. From Alfred John Jukes-Brown’s Building of the British Isles (Jukes-Browne, 1888), in which he showed paleorivers, albeit only on a few maps, and somewhat schematically, to James Dana's first maps of North American paleogeography (Dana, 1863). By 1900 Albert August Cochon de Lapparent (Lapparent, 1900) felt confident enough to draw the first series of global paleogeographies, including a best guess at what was happening in the Atlantic and Pacific. But in all these cases the maps were still land-sea maps.
It was to be in Germany that geologists finally started to bring together crustal architecture and paleogeography as Hunt had originally advocated over 30 years before. From Franz Kossmat’s geological history of land and sea distributions (Kossmat, 1908), albeit heavy on text and light on maps, to Theodor Ardlts ‘Handbuch der Palaeogeographie’ (Arldt, 1917). But, with Alfred Wegener (Wegener, 1912), the potential to put together continental drift, palaeobiogeography, crustal architecture and Earth structure within paleogeography, seemed within reach. Indeed all of these elements were discussed in a single book by Edgar Dacqué in 1915 (Dacqué, 1915). The consequence should have been the first atlases of paleogeographies on plate reconstructions. “Should have been,” that is. Unfortunately, 1914-18 was a terrible time to be a German scientist trying to promote ideas to American and European audiences. And so, as a sad consequence of contemporary politics, there was no atlas, and development stopped and much of this literature was largely forgotten.
Or rather, almost forgotten.
The Yale View of Paleogeography
When in 1904 Charles Schuchert joined the faculty at Yale as Professor of Paleontology he was faced with a problem, how to teach the breadth of geology. His solution was to use paleogeographic maps to show how the Earth had changed over time. It was to become a life-long passion.
Schuchert knew the German work (his parents were German émigrés) and he was well versed in the 19th and early 20th-century geological literature, including that of Hunt. He was also a colleague of Joseph Barrell, one of the founders of modern stratigraphy. Consequently, Schuchert not only took Hunt's workflow, but also emphasized the importance of constraining time. For Schuchert, a paleogeographic map representing a large geological interval, such as the whole Cretaceous, was meaningless, given the major changes that occurred over even the shortest of geological intervals.
The resulting paleogeographic atlas of North America, first published in 1910, comprised 60 maps at much higher detail than before and set the tone for paleogeographic research for the rest of the 20th century. Considered together with paleo-climatology and -oceanography these paleogeographies could provide information on depositional systems. When this was linked with structure (it was Schuchert who first stressed the importance of understanding deformation by palinspastically reconstructing the past geography - deformable plates to you and me) this integrated view could have huge benefits for petroleum exploration (Schuchert, 1919).
Figure 3. Charles Schuchert’s paleogeographic map of the Turonian of North America
Missed Opportunities and Continued Frustration
And yet, 25 years after Schuchert's first maps, we find another petroleum geologist, John Emery Adams (1943), lamenting that paleogeography was still underutilized in the industry. Yes, there were more maps being drawn, but these were mostly local in extent, and more often than not more facies map than paleogeography. The standout exception was the work of Alexander Du Toit, another geologist familiar with the German literature and especially Wegener’s work. He had put all the components together to generate the first paleogeographic reconstruction of Gondwana back in 1937 (Du Toit, 1937) having already published a restored fit for South America and Africa (Du Toit and Reed, 1927). But hey, he was in South Africa and what did he know? Quite a lot as it turned out. But in North America and Europe little was done.
Adams suggested three reasons:
Having spent my career building paleogeographic maps, I empathize with Adams's frustration.
And yet, here was a great exploration opportunity, as Adams realized. Because if you put paleogeography together with reconstructions of climate and oceanography you could potentially predict source and reservoir facies, and what a great exploration advantage that would provide.
Plate Tectonics and the penny drops
Adams was to include some of these ideas in his eulithogeologic maps, which were very much a precursor to the play concept.
The importance of bringing paleogeography together with depositional systems, structure, paleo-climatology, and -oceanography was further developed by Marshall Kay a few years later (Kay, 1945).
But, it was to be another 30 years before the Industry realized what they had been missing when suddenly all the pieces fell into place, metaphorically and, as it happened, literally. This was the advent of plate tectonics. What the German workers had recognized and discussed at the turn of the century, now had observational support and a unifying mechanism (Heezen, 1960; Heirtzler, Pichon and Baron, 1966; Hess, 1962; Vine and Matthews, 1963; Wilson, 1963; Wilson, 1965).
Suddenly, geologists were rushing to plot their exploration data on the new plate reconstructions, together with paleo-coastlines and land-sea distributions. The result was an explosion in paleogeographic research with companies either generating their own maps internally or working with research groups to do so.
It was the late 1970s and exploration following the oil crisis of 1973 was in full swing. Great... But these were still land-sea maps (coastlines), and there was an increasing problem of how to deal with all the new data, especially now that this had to be rotated onto plate reconstructions which multiplied the volume of data created by orders of magnitude.
Paleogeography, Computers and big data in the Windy City
The Hinds Laboratory, home to the Department of the Geophysical Sciences at The University of Chicago, is one of those architectural 'wonders' that wins awards for architecture, and everyone 'wonders' why. In the 1970s and 1980s, the second floor was home to the leading figures in quantitative paleontology. Nothing short of the analysis of the entire fossil record. Big data indeed. The result was the discovery of the five great mass extinctions (Raup and Sepkoski, 1984; Sepkoski and Raup, 1985).
In another corner of the second floor, Fred Ziegler was also manipulating large datasets using early computer systems, this time to build paleogeographic maps (Ziegler et al., 1985).
Fred's background, like Schuchert’s, was Paleozoic paleobiology, especially the use of fossil assemblages to reconstruct paleobathymetry. It was to be this interest that was to differentiate the Paleogeographic Atlas Project and the students it spawned. Because Fred’s maps included reconstructions of paleo-bathymetry and paleo-elevation – the paleo-landscape. Schuchert had talked about this, and indeed there had been attempts to show paleolandscapes such as that of Pepper et al (1954), but those of the Atlas project were systematically constructed based on the underlying tectonics. They were also global in extent, constrained in time to stage level (probably the highest realistic resolution at a global scale), and took some account of palinspastic changes following the work of Kay (Kay, 1945) and Schuchert.
Fred's work had three immediate consequences.
First, the reconstruction of landscapes was key to understanding depositional systems because it was on these paleo-landscapes that the rock record was built. A particle sees topography, rivers, and oceans. It does not see mantle convection or hyper-extension, at least not directly. Weathering and erosion, transport, and ultimately deposition are a function of what happens at the surface.
Second, if you could model depositional systems, then you could model source, reservoir and seal facies, as Adams had suggested back in 1943. This led Judy Parrish, another of Fred’s students, to take the new paleogeographies, use these as the boundary conditions for her parametric climate modeling and then to take the results to retrodict (predict past events) the distribution of ocean upwelling and through this the areas of potential organic carbon accumulation - source facies (Parrish, 1982; Parrish and Curtis, 1982).
The third consequence was data management. Underpinning the new atlases of paleogeography were some of the first computer-based geological research databases. What Fred and his students realized as they built these was the need to better ‘know’ the data itself, specifically its provenance and reliability. ‘Big Data’ can be a very powerful resource, but only if the data is well-constrained. Unconstrained data is simply big bad data and that is worthless.
What Fred did was to find ways to qualify data quality and mapping confidence and provide an audit trail for interpretations. The confidence schemes Fred derived were simple (Ziegler et al., 1985), a categorization of 1-5 where “1” indicated caution and “5” represented the highest confidence. But that simplicity ensured clarity and, more importantly, that the databases would be populated. As Markwick and Lupia later wrote, having worked with Fred, “A database must be simple enough to be used, but comprehensive enough to be useful” (Markwick and Lupia, 2001). The Atlas Projects databases were then linked to the source data through a reference code to computerized reference database with physical copies of all papers stored alphabetically on shelves around the walls of Fred's workroom.
Figure 4. Fred Ziegler's Cenomanian map of North America. The use of computer databases and representation of paleotopography and paleobathymetry
Today, 50 years after plate tectonics, and 150 after Hunt, we are spoiled for choice by the plethora of maps that are readily available online such as those of Chris Scotese and the beautiful photoshopped images of Ron Blakey, which adorn many of the posters and presentations at AAPG each year.
The ideas of Hunt, Schuchert, Adams, Kay, and especially Ziegler have been developed and expanded, not least by Fred’s students, including Chris Scotese, who has perhaps done more than anyone else over the last 40 years to promote paleogeography. My own small contribution has been to build on Fred’s methods to improve paleogeographic boundary conditions for climate modeling (Markwick and Valdes, 2004), further developing the mapping workflow (Markwick, 2019) and then applying these methods to exploration through the development of the lithofacies prediction methodologies that ultimately became CGG Robertson’ Merlin and Getech’s Globe products, both of which used detailed global paleogeographies and Earth system models to retrodict depositional systems, as Adams had advocated back in the 1940s.
Figure 5. As Hunt, Schuchert, Adams, and Ziegler had all recognized, the greatest potential of paleogeography as an exploration tool has always been the ability to represent, analyze and understand all the components in the system. In this example to then use these to retrodict organic carbon and clastics for any time interval.
And yet, like Adams back in 1943, it feels that despite all this progress, for most explorationists paleogeographies are still only seen as backdrop images for presentations and montages rather than a key exploration tool. That is a great shame.
It is time to get out the colored pencils …
This article was first published in the August issue of AAPG Explorer. It is based on a talk I gave at last year's AAPG meeting in San Antonio. My thanks go to
Matt Silverman and Amanda Haddad who chaired the session, “Step Changes in Petroleum Geology: Historical Challenges and Technological Breakthroughs”, and especially to Matt for his kind invitation to write this article for Explorer. I am also indebted to Brian Ervin and Matt Randolph of AAPG in Tulsa who did such a great job with the layout.
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A pdf version of this blog is available here for download
“The sun was in our eyes…”
“The sun was in our eyes…”
After 20 years I had finally bought a road bike. It was great fun. Much had moved on since my steel-framed Dawes Windsor touring bike from the early 1980s.
The countryside around Otley is ideal for cycling, with enough hills to test even the most fit of athletes, some relatively quiet backroads, and a range of great views. I was getting out for up to 50 miles (80 kilometres) a week and I was starting to feel better for it.
But, as I lay flat on my back on the pavement staring at the sky, the joys and health benefits of cycling seemed a little less clear.
COVID-19 has rather stolen the headlines of late, with other major concerns such as the ‘obesity crisis’ and global warming pushed to the inner pages. But this has ‘suddenly’ changed with reports about how obesity may make us more vulnerable to COVID-19 (Actually, this was being reported in the early days of the pandemic https://www.nytimes.com/2020/04/16/health/coronavirus-obesity-higher-risk.html) . Boris Johnson, the UK PM has now announced that he is to promote cycling and that GPs will prescribe bicycles to mitigate obesity.
Although one hopes not to be taken orally.
With atmospheric carbon dioxide concentrations reaching 416.39 ppm in June (https://www.esrl.noaa.gov/gmd/ccgg/trends/), even with lockdown, and rapidly heading to Miocene values, a geological time that ended some 5 million years ago, could this also be the start of mitigating both climate change and obesity by getting the population away from cars and out walking or cycling?
But this needs to be more than a headline and more than just lending someone a bike.
I was certainly minded to think on this as I lay flat out on the pavement...
A car heading towards me had cut across me into a side road without stopping. Unfortunately, I was in-between. I remember being hit, then nothing, and then looking up at the sky and people around me.
Ok, so there are bad cyclists, and certainly, in some of our cities, there are idiots without helmets or lights or, unbelievably, brakes, who are a threat to everyone not least themselves.
But car drivers have the upper hand. No matter how bad the cyclist, if you hit them in a car, the cyclist will come off worse.
So, let me suggest some ideas to mitigate the risks and get more people out and fit.
Some of you will disagree vehemently with some of these I am sure.
Grounds for a potential conflict in the kitchen..
What can Governments and planners do?
What cyclists can do
What drivers can do
At the end of the day, I was lucky. I didn’t have a broken femur as initially thought, and my shoulder is still in one place, the right place. Yes, I did have to cancel a month of business meetings, but I lived to cycle another day, albeit with some ‘major’ scars to remind me of how vulnerable life is.
But in the two years since my accident, I have only ventured out on my bike once… That is not so good
"The sun was in our eyes" is a very poor excuse indeed.
A pdf version of this blog is available here for download
Field sketching in geology: time to think
Field sketching is something that many geology students dread, at least those whose departments still take them outside to see rocks in their natural habitat.
“What am I supposed to draw?”
“I cannot draw”
“I have an iPhone so why do I need to draw?”
Part of this reticence is a fear of what our colleagues will think when they see what we have drawn. And certainly, the sketching of some of our past MSc’s, who will remain nameless, has erred towards the surrealist movement more than one might hope. But this belies the fundamental reason for sketching in geology. The aim is not to create a Rembrandt. If it were, we would be issuing oils and watercolor paints (tempting for next year). The objective is to help us to observe, to think and to understand what we are looking at. That is also why the iPhone, brilliant that it is (and it is certainly part of my workflow as you will see), does not make sketching redundant.
So out with the sketchbook and pencils.
Figure 1. The view east from near Aren, central Pyrenees (Locality 1.4. on the Leeds MSc course). So much to take in so where do we start?
Geology is a highly visual subject and a very diverse one. Like all science, it is grounded in primary observations.
But the diversity of what we need to consider for us to understand those observations gives us a problem. There is so much to take in.
Where do we start? In Spain, the first thing we get our MSc students to do when they look at an outcrop is to draw a sketch.
For me there are three principal reasons for starting with a sketch:
A workflow for sketching
This is how I go about a sketch. This is not the only way, and others will have their own, preferred methods. My background (in the very distant past) was art, which may bias my approach. I have included links to some other resources at the end of this article.
1. Decide on how much of the view you need to capture
The first question is how much of the view to capture. This depends on the focus of your study. In the example used in this blog from the central Pyrenees, the focus of this outcrop is the seismic-scale stratigraphic relationships and what they tell us about the evolution of the underlying structure, and what that structure might be.
Figure 2. The first step is to identify what part of the view you need to sketch. This will depend on the scientific subject you are investigating.
2. Use the full extent of your notebook or input device
For sketches of large outcrops, especially if, as in this example here, you are capturing seismic-scale features, use the full extent of your notebook page. Ideally, use your notebook in landscape orientation across two pages. This gives you more space to add notes.
Figure 3. Use a notebook that you can place into landscape orientation.
3. Identify the central vertical and the edges of the view you intend to draw.
Again, using your notebook in landscape orientation can help, with the central vertical being the spine of the book. Mark in the left and right limiting verticals and keep to these extents
4. Identify key reference points and mark 3-4 of these on your page (useful as a guide especially if you are not confident in your sketching
If you have a field notebook with ruled feint lines and other lines (or a square grid) then these provide you with a very useful guide that can be lined up with key points in the landscape
5. Draw in the horizon
Drawing the horizon and foreground limits will define the extent of the sketch. These are the first lines I draw. I tend to draw from left to right in one go, but sometimes it can be useful to draw away from the edges and center references points.
Use your pencils held at arm’s length to get a sense of scale and perspective.
By constraining the extent from the outset, you can avoid running out of space. There is nothing worse than starting a ‘great’ sketch and finding that all the action is off the page.
Figure 4. The first lines on the map are the horizon and foreground limits that help define the extent of the sketch.
6. Add location information and azimuths
Add the locality number and other spatial information. This should include the date and weather conditions. The latter is useful for understanding what you can and cannot see.
Use your compass to identify the azimuth of your key verticals on the page and write this information as a 3-digit number at the top of the page in line with each vertical. Add north, south, east, and west as appropriate.
In the past, I have put this locality information on the page first, but having run into space problems I now generally do this after I have drawn the horizon and baseline, so I at least know what space I have. Note that in this example the vertical axis of the sketch is exaggerated with respect to the original photograph. This means that I can record more information.
This is also the point when you can add distances and other measurements. This is always less easy that one would think. In this example, the distance along the foreground from north to south is about 2-3 km. It looks less in the photo! As for the distance to the far hills? We can estimate this, but there are better ways available. Maps and Google Maps! So, the advice is to pencil in estimates but to then revisit your sketch once you are back at your computer.
Figure 5. Add annotation, including details of the locality and geographic orientation (azimuths). You can add the locality information first, but doing so after you have identified the best use of the page for your sketch extent means that you can place the data where you have space.
7. Draw in the middle ground
The aim of this is to further constrain geometric relationships and distances on your sketch. Follow plateau tops or hill slopes into the valleys. This gives you more of a framework for understanding the geology.
Figure 6. The middle ground provides the rest of the framework of the landscape you are capturing. Follow slopes down into the valley, cliffs and tree lines. This will help tie your sketch together.
8. Draw in trees
Why draw in trees and vegetation? I find that adding landscape features such as trees can help me better remember the landscape and, more importantly, provide reference points and guides to scale that I can then see in related photographs. The vegetation also reminds me of the extent of the visible geology.
Figure 7. Adding trees and buildings provide indications of scale. They also provide reference points for locating where you are.
9. Locate and capture key geological features
This includes features such as bedding or unconformities that you want to draw attention to.
Figure 8. The final drawing stage is to add bedding and other key geological features that have not already been represented by the previous stages.
10. Annotate geological features
Include any information on bedding geometry, apparent and real dip, major color changes. Any relationships between the landscape geomorphology and underlying geology. Include notes to any scaling issues resulting from your sketch (this is ad to memory for comparing with the photographs you take).
Include notes of any uncertainties about interpretations or things that you want/need to investigate further.
Figure 9. The final stage is to add geological annotation, dips, notes, ideas, hypotheses to test.
Whether or not you should add color to your sketch is highly contentious (Hi Amicia 😊). An advantage of keeping your sketch in black and white is that you can then scan or photograph it and add color in Microsoft Powerpoint, Apple Keynote or other graphics software (see below). However, I have found over the years that color helps me remember what I am looking at. In figure 10, I have colored the trees because they are not the geology, but they do help bring out the depth of the landscape and what parts are exposed. I have also colored the red-beds because of their importance as a marker unit.
Figure 10. Adding color is highly contentious as I found out last year when one of our Ph.D. students posted a questionnaire and competition on Twitter Amicia won... black and white came top. But sometimes color can help you remember the landscape. This is less of an issue when the sketch is supported by digital photographs. Here I have colored the trees which provide information on what geology is exposed and what is not. I have also colored the red-beds as a key marker unit.
12. Photograph your sketch
Just in case you drop your notebook in a puddle, you leave it in the coffee shop or at the outcrop, or it is stolen and eaten by goats. Yup, it happens..
13. A sketch is never finished
Earlier, I left open the question of dimensions, the height of the mountains, distance to the background hills. Traditionally, and even today, it is good practice to estimate these in the field (your estimates will get better the more you do this), but today we have other tools to help us in addition to checking a physical map on our return. The easiest of these is Google Maps.
I touched on the use of Google Maps in my Field Photography blog last year.
You can use Google Maps to look at relationships that were not clear to you in field and also to measure distances if you don’t have a physical map available. Do be careful about using the 3D perspective view (as picked here) for absolute dip measurements. My advice, is don’t. But the overall stratal geometries will usually be fine.
Figure 11. The Google Map view of the locality in this field sketching exercise. Immediately you get much more information on relationships, the fanning of dips and especially the sub-Late Eocene unconformity. Information that you can add to your sketch. Note that the lithological variations in the Paleocene-Eocene section become much clearer too, with the limestone unit (the Alveolinid Limestone) is a much more prominent feature. This was discussed in my blog on field photography last year.
Figure 12. The addition of distances and elevations (in black) read from either Google Maps or a printed map, depending on which is available. Using simple geometry, you can then start to estimate unit thicknesses.
There is another important lesson here: your sketch is never finished.
As a student, or indeed any field geologist, do not draw your sketch and then walk away. By checking your observations back at base (hotel, office or tent) you can better enhance your understanding.
Use all the tools available to you
With access to the internet and maps back at your office or hotel you can manipulate your field sketch in a graphics package to extract more information. Using maps and publications you can test out some of your hypotheses, answer questions that you wrote to yourself on the sketch, and see what others have made of the outcrop. This might mean that you have to return to an outcrop (if that option is available) as you revise your hypotheses and ideas.
The aim here is, as much as anything, to help enhance your understanding of the outcrop.
In this example, I have used Microsoft Powerpoint because I always have Microsoft Office on the laptop I take into the field. This means that I can simultaneously build any presentations that I might be asked to give.
This is where the black and white versions of the sketch give you the most flexibility and where you can add color to pick out key geological features you want to draw attention to.
In the examples here I have colored the sketch to bring out the age of units and bedding, dominant grain size and depositional environment (part of my input for a paleogeographic map).
Figure 13. An advantage of keeping your sketch uncolored is that you can add color later to a digital version as here. This example was constructed in Microsoft Powerpoint with the sketch first lightened and then polygons drawn to represent unit age. This can then be added to a presentation if you are asked to give one.
Figure 14. In this example, the units are colored according to the dominant lithology identified in the sketch and from the related geology map.
Figure 15. This example shows the same sketch now colored according to the dominant depositional environment.
15. And the answer is?
At the beginning of this blog, I said that the aim of this outcrop was to identify and investigate the stratal relationships and from this interpret the nature and evolution of the structure that caused them. As in all good Agatha Christie novels, I have left answering this to the very end.
This is best examined by constructing cross-sections using high-resolution geological maps (available from the excellent IGME and ICGC websites) or even better, seismic. Here let us look at this as a quick back of the envelope interpretation using the sketch.
As drawn, the dips decrease to the south. This ‘fanning of dips’ is consistent with a growing structure to the north, conveniently just off picture. We are seeing the steep southern limb of the resulting anticline. The fanning appears to start with the Maastrictian-Paleocene red-beds, which indicates that this is a growing, positive topographic feature at the time. This is why this unit is such an important marker bed in this sketch.
The question is what is the vergence of this structure? Here I show one interpretation.
Figure 16. A back-of-the-envelope structural interpretation based on a first look at the stratal architecture. This does not immediately answer the question about vergence of the underlying structure (although we do know this from other sources) but does give us an age for the activity which is Maastrichtian – Paleocene.
The general guidance is to use a pencil in the field and to then generate an inked-in version each evening. This has the benefit of ensuring you have two copies of your notes.
Figure 17. A sketching kit. The key elements are a notebook that can be used in landscape orientation and a good pencil.
My personal preference is the Chartwell 2006Z top opening survey book. Although this lacks the waterproofing and very useful look-up information contained at the back of the Rite in the Rain Geological Notebooks, which are great, I do like the fact that I can open up the Chartwell notebook in landscape orientation which gives me two pages for sketches. It also has two parallel lines which provide great reference lines for sketching and also for logging when in portrait view.
Pencils and Pens
Mechanical or regular pencils are a matter of personal choice. In the past I used Staedtler HB pencils with an eraser, but then I make sure that I have at least 6 with me each day, and 2 pencil sharpeners. But two years ago I tried out the Pentel Graphgear 1000 mechanical pencils, after reading numerous reviews, and I have to say they are impressive (all my nieces and nephews got them for Christmas! Lucky them...).
To keep my pencils organized I use a Derwent Canvas Pencil Wrap . It takes up limited space and unrolls to give you easy access to pencils, pens, crayons and pencil sharpeners.
There are so many different colored pencil crayon brands on the market and you will probably have your favorites. I tend to pay a little bit more for my pencils to minimize broke leads - there is nothing worse than finding that the pencil leads are broken throughout the pencil – you pay for what you get!
Brands like Derwent and Faber-Castell are very good. I can recommend the Faber-Castell’s GRIP pencils which are very good quality for the price with a good range of useful colors. I currently use a set of Faber-Castell Polychromos Colour pencils. They are great pencils, but probably more than needed for field sketching or seismic - I use them because I enjoy more artistic sketching as well as field sketching.
This is all very much a personal and budget choice.
There are a range of good A4 and A3 Waterproof clipboards on the market. Check out Amazon or your local art or hobby store (viz., Hobbycraft in the UK, Michaels in the US).
Cameras and Phones
Most of us still take large digital SLR cameras into the field. But the cameras on phones are now so good that in most circumstances these will meet your needs and certainly be ideal for capturing your field sketches. The panorama mode on the iPhone is especially useful for capturing big picture landscapes such as the example in this blog.
Please remember to save your photos to the cloud or to your computer. I use Dropbox or iCloud as further backup insurance.
There are some useful guides available on the internet of which the following are good to check:
Maggie Williams (University of Liverpool). “Field sketches and how to draw them”
Geobus (2016). “How to draw a field sketch”
Geological maps for study area:
A pdf version of this blog is available here for download
A higher resolution version of the field photo used in this example can be downloaded here. Feel free you use this to practice your sketching.
Bring the photo up on your computer screen, iPad or TV and then sketch it into your notebook. Have fun!
Creativity and communication are inextricably linked in science. Ideas in isolation, stay in isolation. For such a visual science as geology, good communication is as much about graphical presentation as the clarity, depth, and veracity of scientific arguments. The current wealth of powerful graphics and mapping software should make this easier. There are certainly some impressive publications out there that maximize this power. But sadly, not all. This is all the more important when building commercial products, where the look and feel impact user perception as much as scientific correctness.
I have always been frustrated, if not a little impressed, that a client who has just bought a technical report will instantly find the one typo in 100 pages of text and imagery.
The concern, as a business, is that the client’s view of that report will then be forever tarnished by that discovery. If the typo is compounded by scrappy graphics or a poor choice of color scheme, the reader may not get as far as the science and a failed sale is the result, or even worse, no future sales.
And yet, too many knowledge-based companies focus only on their scientific cleverness or just getting the project done.
Twenty years ago, that may have been enough. Hand-drawn figures, typed manuscripts and photocopied images from papers were accepted. That is no longer the case.
This is not only because of tighter copyright laws (understandably) but also because client expectations are much higher. Consequently, the overall look and ‘feel’ of a scientific report in knowledge-based businesses is critically important. It is about perception and most of all trust.
In my last directorial role, I was fortunate to hire an excellent editor and a talented draftsman to make the process easier for all and ensure quality. But you need buy-in from all your staff to make this effective. Otherwise, the pressure will fall on your editing department who will spend more and more time making staff work fit the standards you have set.
Everyone involved needs to understand why a client’s perception of their work is so important and through this to get them to care about what they produce.
The Italians have a wonderful phrase that encompasses my philosophy for writing and visualization, “La Bella Figura”.
Although the phrase literally means “beautiful figure”, it encompasses a far broader concept, the central importance of making a ‘good impression’ that makes what you do more meaningful.
With that in mind, and in the tradition of the internet, let me offer 10 tips for designing and producing knowledge-based products.
In this blog, the focus will be on writing. We will look at generating figures and digital products in a future article.
When thinking of form and function it is impossible to ignore the Renaissance and the rediscovery of the lessons of classical Greece and Rome
1. Care about what you build
This is the key starting point. If you care about your work and what others think of it, you will do all you can to ensure the quality of what you build.
This is fundamental to the concept of la bella figura
One way to encourage this in business is to include the names of all those who built the product in an author list. This provides a sense of ownership but also of responsibility.
2. Define the take-home message from the start
Different readers will need/want to extract different levels of information from a technical report.
For senior managers it is about the key take-home message - they will not have time for anything more. Get this written up-front and make it clear.
This take-home message is the "elevator pitch" that you will frequently see referred to in marketing guides - you find yourself in an elevator with a potential client and have three floors to explain what you do and why they should buy it. The number of floors varies with the author and vintage of the elevator.
In a presentation, it is often useful to state the take-home message at the beginning of your talk, in case you lose management during the presentation, and then to finish your presentation with the same statement.
In print, the take-home message can form a key part of what is frequently called the “Executive Summary”, aimed, as the name suggests, at executives with limited time.
The Executive Summary should be a distinct, independent printable page that can stand alone if necessary.
As an example of a summary with major ramifications, have a look at that of the IPCC who direct their summary to policymakers with a series of take-home headlines.
If you search for “Executive Summary” on Google (other search engines are available) you will find numerous websites focused on the design of Executive Summaries.
3. Be organized: Everything has a beginning, middle, and end
Start by following the fundamental rules of writing. The most fundamental of which is that a report or presentation, just like a novel, will have a beginning, middle, and end.
In the beginning, you outline what you are going to say or do, in the middle you say or do it, and at the end, you conclude by saying what you have just done.
Now, this may appear a little simplistic. It is. But starting with this simple structure can help facilitate your writing. You can add detail and embellishment later.
This also applies to presentations. Ending a talk with a blank screen – a particular bugbear of mine as Leeds students will know - is a missed opportunity, since this last slide will likely stay longest on the screen
The simplest structure of any report, presentation or novel. Everything has a beginning, middle, and end
In this final slide from AAPG 2019, there is the usual outcrop picture (a version of the photo I began the talk with and which was used to set up the problem being addressed), here with a take-home which refers to the importance of using sketches and maps to manage and photo analyze diverse datasets. The sketch was animated to add a further dimension to the end of the talk and draw attention to the slide. This is also where you might include acknowledgments to funding bodies or other authors
4. What? Why? How?
A beginning, middle, and end provide the overall structure. But what of the actual content?
This will depend on the application and audience. For papers, reports, and presentations I usually approach this part in the same way, with an A2 piece of blank paper in front of me on which I sketch out the structure. A whiteboard will work equally well, or touch screen for those of you not familiar with paper and pen.
To start with, consider the following:
I write these out first on my piece of paper or whiteboard.
Remember that the what, why and how will fit within the beginning, middle and end.
Adding the “What?” “Why?“ and “How?” forces the writer to think about their study. What it is, and most importantly why they are doing it
4.1. The “what?
The “What?” can be divided into two sections/slides:
And yes, there is a difference between aims and objectives:
For example, you might want to understand why the Earth's climate changes. That would be your aim. The objectives might then include (1) measuring CO2 in the atmosphere over 10 years and producing a table and/or graph to show this; (2) a review of past observed changes in climate written as text (or a graph); (3) running a climate model with different atmospheric CO2 concentrations with physical results.
The key differentiator is that each objective has a tangible outcome. The aim, in contrast, need not be achieved, frustrating as that will be (been there...). This also means that for any project, and certainly for a commercial report, you should be able to tick off each objective on completion within your project plan.
4.2. The “why?
The “Why?” is critically important. If you don't know why you are doing something, then why on earth are you doing it.
I usually include a section or slide with the title of "The Nature of the Problem". This includes a statement of the problem to be solved and its history.
In a paper "the why" can include the background to the subject. Frequently the background will form a separate section to do service to those who have gone before, which is very important in understanding what needs to be done and why. Understanding the current and past literature is essential in my view.
(There is certainly a place for exploratory science, where you don’t know the why, nor the possible outcomes, but such studies are not the easiest to get funded, for obvious reasons).
5.3. The “how?
The “How?” relates to the "Data and Methods", usually included in any paper or presentation as a section in its own right. This includes the data used as input to whatever you are doing.
The methods include any techniques or workflows that will help the reader understand how you have solved the problem and also ensures that they could if needed, replicate what you have done. This is the basis of good scientific practice, whether academic or commercial.
We have now posed the “What?”, “Why?” and “How?”, and it is time to show the results of the “What?”. This is usually titled, unoriginally, but clearly as a "Results" section.
A “Discussion” can follow which takes the results of the objectives (part of the “What?”) and discusses it within the context of aim(s) (the “What?”). This is the section in which you as the author get to the nitty-gritty of the project and what it means.
The conclusions bring the report, paper or presentation to an end. Here you succinctly reiterate the take-home message, and any other key headlines you want your audience to walk away with.
We can then top and tail the report with the “Executive Summary” and bibliography, acknowledgments and appendices
In presentations, we can provide a talk structure for the audience to follow. For my talks, I will frequently use labels at the bottom of the screen that shows where in the talk we are (darker blue fill in this case). The overall structure is the same
Here, we can see this applied to an actual slide from a talk. In this case a talk on paleogeography
In reports or papers, we think of the ordering from top to bottom as given in a Table of Contents, rather than as the left to right progression in a presentation
5. Hyperlinks and document navigation
As a reader, it is important to be able to find information quickly within a text or database(s). This is similarly important in a report.
Navigating within this structure and through the content is much easier in the digital world. Software such as Adobe InDesign or Microsoft Word will allow you to quickly add sections, tables of contents, bookmarks, and indexes.
In digital products, the use of hyperlinks is common and very useful, but do check that hyperlinks work. The use of relative paths and a systematic folder structure for your associated files is strongly recommended and something to establish before you start a project.
6. Keep it simple and succinct
.Clarity and simplicity are key if you want to be fully understood. Do not try to prove your cleverness by making what you produce only decipherable by you.
As someone who can be rather ‘Victorian’ in my writing style, this has been a hard-learned lesson - one of my colleagues recently referred to my writing style as “chatty”... I do not think that this was meant as a compliment.
In the age of social media and especially Twitter, attention spans are short, and you need to convey your message as quickly and precisely as possible to your audience.
Most scientific journals now provide a supplemental data section that will allow you to place additional information outside of the main paper. This shortens the main text, whilst still enabling fellow scientists to replicate what you do, which is fundamental to the scientific method
7. Choose your font(s) with care
Frequently, choosing a font is something of an afterthought. That is a shame because much of what your reader will see is what is written, i.e, the font (typeface).
Journals will have their own preferred sense over which you will have no control, but if you are setting up a business you may want to consider the look and ‘feel’ of your written word.
In choosing a font, think about how you want your clients and readers to view your work. A classic, academic look (viz., Times New Roman font) or a more modern fresher look (such as Century Gothic or Avenir).
Also, consider whether the font will be used online or printed or both. There are a number of websites that can help you chose the right look. But in so doing also bear in mind that some fonts are freely available on all platforms (Windows, Mac), others are not, or, worse, will require a license.
Once you have a font assigned with a look that is 'yours', keep to it.
My preference has been to go with Century Gothic for online work (I prefer Avenir, but it is not freely available on Windows) and Garamond for printed text. Both are readily available and free.
A comparison of three different fonts with different ‘feels’ and applications.
One further point on fonts, if you will forgive the pun, is not to mix too many fonts in the same document or presentation.
8. Check your spelling
With spell checkers built into Microsoft Word and other programs, there is no excuse for typos.
There are also 3rd party programs that are worth considering. I can recommend using the free version of Grammarly which I have found to be accurate and informative. This is the software I use regularly.
Kilometres or Kilometers? British English or American English
9. Choose your language and keep to it
This is becoming increasingly contentious given increasing nationalistic buffoonery, especially for English speakers where the language can be quite fluid and varies by region. I live in Yorkshire… enough said…
The main choice for those of us writing for the international market is whether we use American English or British English. Having spent eight years of my life in Chicago and having academic co-workers across the US and many clients in Houston and around the world, I do find myself mixing these two English variants.
At one level, this does not matter. At the risk of being trolled for suggesting such a thing, bear in mind that prior to Noah Webster's first Webster dictionary English in the 18th century, spellings and pronunciations were interchangeable across the Atlantic, gray and grey, labour and labor, etc.
Journals and publishers will have their own strict rules about spelling and language that you will need to keep to. But if you have a choice in setting up a business, then go with one and stick to it. I suggest that If you do international business that you use ‘American’ English because it is now more widely accepted and the form that most people learn and experience via the internet, film, and TV.
10. Print out the final results and ask yourself one simple question: would you pay monies for this?
I find it useful to print out what I produce to give me a sense of what the reader will experience.
This can be also important where you are binding material in a book or magazine format and where margins become very important but may not be so onscreen.
Looking at the results are you proud of what you have written and produced?
Think la bella figura
Always print out what you write and create and ask yourself one simple question: would I pay for this
There are a large number of guides to writing, including physical books and online resources.
I can recommend “The Elements of Style” by William Strunk, Jr. This is concise, and an easy read (a few hours).
”The Chicago Manual of Style” produced by The University of Chicago, is a more comprehensive reference book and one that sits on my shelf for emergency reference. This book is now in its seventeenth edition.
For a discussion on the meaning of the phrase "bella figura" have a look at this interesting article by Carol King (2012). Italy Magazine. “Bella figura and brutta figura: Italy’s beauty and the beast”
I use Blurb.com for publishing. Check out their website for guides on layouts.
A pdf version of this blog is available here for download
Finding time and colour in Venice
The quiet and colors of the back streets of Venice. May 2013, Nikon D600, Nikon 24-85mm at 24mm at f/4.5 hand-held at 1/80 at ISO 400. Away from the tourist sites you can begin to appreciate a world without the dull, continuous hum of road traffic. This is one of my favourite shots from my trip to Venice and one I have printed many times - the best result has been to print on a textured watercolour inkjet paper (I use Canson papers, which I can highly recommend). To me it is about the colours, the light and the architecture. That is the joy of photographing in Venice.
When thinking of Venice, probably the most common images are of canals, gondoliers, the Rialto Bridge or St Marcos Square. But for the photographer, artist and cultural historian there is much more to the city that can be found in the streets that lie just beyond the tourists
Venice is a place that lives up to expectations. It is a beautiful city. As a photographer, it seems that no matter in which direction you look, there is another great picture. As such, it is too easy to forget that people live and work here, locals for whom visitors such as me must be both a boon and a bane.
Thankfully, for all concerned, most tourists tend to stick to well-mapped routes as they rush from one selfie to the next, and it is surprisingly easy to slip into the back streets where you can take time to absorb the history, colour and beauty of the city, enjoy a quiet moment or two over an espresso (surely one of the greatest contributions to the culture of the world since afternoon tea), and most of all appreciate a world without that dull, continuous hum of road traffic.
My last visit to Venice came after a series of business meetings in Milan and a need to take a couple days off to relax. Relaxing is not what I do, so this meant either hiking in the Alps or something cultural. A two-and-a-half-hour train journey from central Milan and I found myself caught up in a torrent of tourists as they rushed from the station to St. Marco’s Square, via the Rialto Bridge and then straight back home, the sound of roller trolleys rumbling in anything but unison. Thankfully my hotel was on the way and I could peel off onto a back street, and away from the turisti, of whom I was desperate not to be considered a part – wishful thinking.
A quiet evening on the Grand Canal, Venice, May 2013, Nikon D600, Nikon 24-85mm at 24mm at f/4.0 hand-held at 1/400 at ISO 400. Photographic clichés abound in Venice, and all are worthy of numerous frames, and few will disappoint. Here the view north along the Grand Canal from the Rialto Bridge
Photographic clichés abound in Venice, and all are worthy of capture and I am sure that few pictures you take will disappoint you. But it is the quiet, the colours and the textures of the back streets that photographically caught my attention. This is not a pristine city. The perpetual damp of the lagoon takes its toll, but that is part of its charm, photographically at least; I am sure it is less than ‘charming’ to try and maintain. The results are building whose walls are not one single colour, or finish, but where hues change on a single building, paint peels back to reveal a depth, and stonework varies as plaster gives way to the underlying building fabric. There is a story and history here at every turn, but also a recognition of city living through a perpetual battle against nature. I know that that is a cliché, but none the less true.
Character born of age and weather in Venice. May 2013, Nikon D600, Nikon 24-85mm at 24mm at f/6.3 hand-held at 1/160 at ISO 200. The details of many of the buildings make interesting compositions with a story. These are people’s homes, so do be respectful
A rainy evening in Venice, May 2013, Nikon D600, Nikon 24-85mm at 85mm at f/4.5 hand-held at 1/30 at ISO 1100. Photographing in the rain never quite captures the moment or the damp, but here in Venice, the mix of light, water and buildings makes the attempt a little easier. Helped in no small way by the presence of umbrellas. Next time I will take a tripod
Light and contrast in Venice, May 2013, Nikon D600, Nikon 24-85mm at 24mm at f/5.6 hand-held at 1/125 at ISO 320. The light and contrast in Venice, like so much of Italy and Spain, plays directly to photography. But in Venice the addition of water gives an added dimension as here. In programs such as Adobe’s Lightroom you can readily experiment with contrast levels. Here I have kept the interior quite dark to emphasize the light beyond. Black and white can work quite well in such circumstances.
The colors of Venice, May 2013, Nikon D600, Nikon 24-85mm at 32mm at f/8.0 hand-held at 1/250 at ISO 125. The canals are central to what Venice is, and the reflections in the water on a clear day make for a great colour palette to experiment with. But, be careful since canals are canals, so keep an eye open for interesting colours, textures and reflections. This may mean zooming into an area rather than a general canal shot as here
Venice, May 2013, Nikon D600, Nikon 24-85mm at 75mm at f/8.0 hand-held at 1/250 at ISO 100. There is so much going in any scene here. The mix of colours, shapes and textures and behind each a story.
So, do take your photos of the Grand Canal, the Rialto Bridge and St Mark’s Square, and the obligatory gondola. They all make great pictures. But, consider taking time to wander. This will help you find some interesting photographic compositions, but it will also allow you to absorb the atmosphere and history of Venice, and a world less hectic. And you will quickly realise why: the dull hum of traffic is absent, and that is wonderful.
Gondolas. May 2013, Nikon D600, Nikon 24-85mm at 24mm at f/8.0 hand-held at 1/250 at ISO 140. Who can resist a cliché! Ahh…, Venice
Photos were taken using a Nikon D600 with a standard 24-85mm lens.
Data management and post-production was using Adobe Lightroom
Printed copies were made using an Epson R3000 A3+ inkjet printer and Canson papers: http://www.canson-infinity.com/en
I do have a photo book from this trip which I can make available for purchase via Blurb if there is interest.
A pdf version of this blog is available here PDF
Data is only useful when accessible. A guide to scanning with the Fujitsu ix500
The Fujitsu Scansnap ix500 scanner
During my Ph.D I built up a substantial research library of papers and notes, which have travelled with me for the past 30 years. For much of that time they been ensconced in boxes, which rather limits their use. Knowledge may be power, but only when its accessible.
Over the past decade the internet has become a resource for reviews of just about every product, device and service and I, like many others, have sought these out to help in deciding on what to buy. It is now time to return the favour and add to this online resource as an actual user of a product.
In this case the Fujitsu Scansnap IX500 document scanner.
Ok, so some of you have switched off already. And it must be said that document scanning tends to fall into the same category as project and data management when it comes to entertainment value.
But if you are faced with a mountain of physical documents and the need to make these accessible, you may start to feel a little differently.
The problem I had to solve was this: an extensive and potentially powerful library of 25,000+ physical documents, scientific notebooks and papers, stored in my basement.
During my Ph.D I built up a substantial research library of papers and notes, which have travelled with me for the past 30 years. For much of that time they been ensconced in boxes, which rather limited their use. Knowledge may be power, but only when its accessible.
Each paper and document was housed in a manila card folder, with a label and arranged alphabetically. This followed the data management methods used by in the Paleogeographic Atlas Project at The University of Chicago, where I did my PhD.
After my house was flooded a few years back, much of this library also ended up a little soggy. Sadly, some of my library was beyond saving, except as the stock for making papier mâché volcanoes, but it prompted me to act.
Although having physical copies is still often the best way to work, access is even more important. Today we have the technology to turn all this paper into searchable pdfs, technology we did not have back in the 1980s and 1990s.
The Fujitsu Snapscan ix500
The Fujitsu Snapscan iX500 is a dedicated document scanner that is compatible with both Mac and PC. The unit I have is still available (ix500) although it has now been replaced by an updated model, the iX1500
The Snapscan iX500 can scan documents up to a resolution of 600 dpi (Color, grayscale) and 1200 dpi (B&W). I have mine set at 300 dpi (color, grayscale), 600 dpi (B&W), which is a compromise of the need to have high enough resolution figure scans, but also ensuring that file sizes are manageable.
With 25,000+ documents to scan, speed is key and the iX500 makes the task tractable. The published numbers of 25ppm for color scanning seem about right in practice. I have included three examples from my scanning workflow in the table below. For each example I used the following settings:
As an explanation of the workflow stages:
“Preparation” refers to removing document covers and staples and ensuring that all pages are separated, especially where papers are water-damaged.
“Scanning” refers to the actual process of scanning through the scanner.
“Post-production” refers to the process of adding the results to my data management system, and where appropriate linking the file to my bibliography database. This also includes any rotation of individual pages using Adobe Acrobat.
OCR (text recognition)
The OCR software bundled with the ix500 is good. On occasions it does fail with an error message on the computer to ask if you want to save the file as images only. From experience if this happens then I recommend rescanning the document to see if it works the second time around. If that fails, turn the document 180 degrees and scan again. I am not sure why this would work, but in most cases, it solves the problem.
Ease of Use
The unit is incredibly easy to use, but here are few things to remember, especially if you ‘forget’ to read the instructions:
Wrinkling of paper sheets due to water damage. If you have a similar problem, make sure that you first separate all the sheets before loading them into the scanner. You may find that you have to load each sheet separately if the wrinkling is particularly bad. Also, be aware that this sort of damage can lead to sheets being fed at an angle through the scanner. Again, this why my setup has the <Continue scanning after last page> switched to “on” because you can then quickly reload the page. The other thing to aware of is that water-damaged paper may have spores and other fungal damage. This may loosen and get into the scanner mechanism. I use an air spray designed for photography to clean any loose material from the scanner.
Size of unit
The iX500 is relatively small and light in weight and sits easily on any desk or table. The quoted dimensions are 292 mm x 159 mm x 168 mm (11.5 in. x 6.2 in. x 6.6 in.). But this is probably easier to visualize in the photo below. The scanner size will not be an issue.
The scanner with the paper feed open, but not with the output tray folded down, which I don’t use. The DVDs provide a sense of scale.
Paper size limits
The scanner can scan up to A4, Letter and Legal sizes. The accompanying user guide states a maximum weight of 209 g/m2 and certainly I would not want to put anything thicker through the unit. For larger documents I use an A3 Brother MFC-J69300W All-in-one printer scanner, which has been great and is highly recommended especially when you can find it on offer.
This is not the cheapest scanner available, but frankly, for the price, it is worth every penny. Expect to pay anything from around $400-500 (c. £400 in the UK).
The ix500 receives great reviews on the internet. Here are a selection of the reviews I have used:
pcmag (UK): Review of Fujitsu Scanscap ix500
TechGearLab: Review of Fujitsu Scansnap ix500
ExpertReviews: Review of Fujitsu Scansnap ix500
Amazon (US): Customer reviews
Amazon (UK): Customer reviews
There are also numerous YouTube videos you can look at to see the scanner in operation.
Field photo of the base of a turbidite sandstone bed showing load structures, flute marks, and trace fossils. The obligatory scale. Early Eocene, Arro, Central Pyrenees.
Digital photography has made taking field photographs so much easier. Immediate results, high resolution, relatively low cost and the ability to take almost unlimited pictures. And then you can instantly upload them to the cloud. How can anything possibly go wrong? Here are 10 simple tips for ensuring it does not.
Photography is an essential part of fieldwork in the Earth sciences.
Today, digital photography makes capturing field information easier than ever before. Immediate, high-quality images can now be achieved even using a smartphone, and results uploaded to a computer or the cloud.
Go back 20 years and the ‘picture’ was very different….
Before digital there was film.
Now for those of you too young to know what film is and who may never have heard of "Kodak" (i.e. anyone younger than 20), imagine being limited to how many pictures you can take, which means that you must choose your field shots with care. Each roll of 35mm film could capture up to 36 images. And film cost. Imagine changing between rolls of film, ensuring the film was not exposed when you loaded it in your camera. Now imagine doing that in the rain, with the back of your camera open to the elements.
So far so good...
Now imagine that you cannot see the results until you have the film processed, which you cannot do until you return home or to a base with either a post-box or photo store, and then it might take a week or more turnaround time between sending, processing and return.
Only then can you see what you captured weeks before.
Imagine getting a nice blank film back... Doh!
There was an 'immediate' film option, which was to use a Polaroid instant camera. But prints were small, and the resolution limited. It was also still film technology, and as already said, film cost.
Thank goodness for digital.
What is there not to like and how can this possibly go wrong?
Well, of course, it can.
Whilst digital makes field photography easier, there are things that you must take account of whether you are taking field photos with Digital or with Film.
In this first blog on field photography, I want to provide 10 simple tips to remember. Although this list is largely designed to help students, it may be useful to others.
(We will look at camera kit in a future blog)
1. Record your location
You need to record where you are.
Some digital cameras have GPS (Global Positioning System) built in, and certainly many/most phones do (if you are within range of a signal). If not, you can buy separate units that plug into most makes of digital camera. I use a Solmeta Geotagger GPS attachment for a Nikon D810. It is pretty accurate, although I usually have a larger Garmin 64s GPS with me if I am in a new area and want more accurate results (and as a double check).
If you don't have a GPS then the traditional approach is to use a map grid reference. Be aware of local grid schemes and what system you will publish. Latitude and longitude are the clearest and most useful for international research (frankly the use of local grid schemes in publications only frustrates; it certainly drives me nuts, having spent my Ph.D trying to translate various national grid systems into latitude and longitude; and don't even mention the Township and Range system of the US).
It is then important to ensure that this location information is assigned to each photograph, either through metadata (digital) or physically written on slide frame borders or the back of prints.
Geographic orientation (azimuth) of the subject is usually derived using a compass, but again, this can now be done digitally. The Solmeta Geotagger GPS attachment I use also records the direction in which you are pointing the camera as well as elevation.
However, I recommend using a compass. This provides a double check of your digital equipment but is more reliable in its simplicity. It is better to do this in the field than question results once you are back in the office.
This information is then recorded in your field notebook; don't rely 100% on digital information. Record what your source of location and orientation was.
2. Get a picture of the overall context
Capturing the geological context of a field subject generally means stepping back and taking a photograph of the whole outcrop and, ideally, the landscape in which that outcrop occurs.
Panoramas are a great tool for this and allow you to then place your detailed shots; this also needs a sketch, so you don’t forget where each is.
Panoramas using film take up a large number of shots. When I first experimented with 360 panoramas back in the 1990s using some of the early Apple stitching tools, a single 360 panorama would take at least 18 - 36 shots. i.e. a whole roll of film.
Digital means that the number of photos needed for a high-resolution panorama is no longer a constraint. What is more, the stitching software has improved tremendously, although it should be said that the Apple software was well ahead of the curve.
Many phones and cameras provide an automatic panorama tool, which is amazing.
As a recommendation always build panoramas using the camera in portrait orientation. This will increase your ability to accommodate for vertical movement when not using a tripod.
Panoramas built from single shots can then be stitched together using either a dedicated panorama stitching software such as PTGui which I use, or the extensions now available for Adobe Photoshop and Lightroom or other photo processing software.
One further thing about context using panoramas. Remember that the orientation of the image will, by definition, encompass a range of azimuths, so you need to ensure that you record this. For limited extent panoramas (not the full 360) record the azimuth of each end of the panorama as a minimum requirement.
If your camera appends azimuth (orientation) to each photography that builds a panorama then you will be able to revisit this later.
There is also another way to check on the context of an outcrop and that is to use Google Maps back in the office or basecamp. With the ability to now generate 3D views of landscapes in Google Maps you can go back to any locality and relook at the context from various orientations. This is a great tool. But it does come with a health warning. In most areas, the landscapes in Google are draped on an elevation model, which means that bedding dips and geometries will be compromised.
Google view of the panorama shown above. The position of person indicates the viewpoint, and the extent by the white lines.
3. Then focus on the detail
With the context captured, you can focus in on key features within the outcrop. This might be fossils, sedimentary structures, or tectonic structures, petrology etc.
If you are focussing in on detail, be careful especially of light and focussing (see below).
Ensure that on at least one version of each picture you have a clear scale that shows dimensions and any possible distortion (see below).
With a high-resolution digital camera with a large megapixel count, you will be able to zoom in and extract detailed clip-outs from a single overview photo in processing software such as Adobe Lightroom. This can help limit / manage the number of pictures you take if this is a concern.
4. Keep track of scale
Size is important. All field photos need to include an indication of the scale. Traditionally geologists have used coins and lens caps, all of which vary in size.
Today, it is easy to buy professional scales used for archaeology or, as I use, for crime scenes (evidence markers are great for drawing attention to key features for students to look at, although chalk body outlines might scare the more sensitive and are probably best avoided…).
The metric system is the standard measurement system for science. However, many of my scales have both metric and imperial given that much of my own audience is based in the U.S.
A word of caution, which also applies to coins as scales, is light reflection and exposure. Although I use white scales (see photos), I now also have a set of grey colored scales, which present fewer light issues.
A 5 cm (2 inch) scale used for smaller features
5. Watch out for distortion
Zooming into a scene can have an unwanted consequence. Distortion. This can get even worse if you get close to an outcrop and then decide to use a wide-angle setting. Not recommended. But is often done.
The scales I use have a circle drawn on which will give an immediate measure of distortion which you can then account for in Lightroom or Photoshop (or equivalent).
For larger extent field shots look for verticals that you can use to constrain distortion. For example, signposts, roadside lamp posts, etc.
A scale ‘square’. The right angle and circles allow for any image distortion to be quickly assessed.
6. Check your focussing and light settings
One of the real frustrations of using film was getting your slides or prints back and realizing that you had set the wrong aperture or shutter speed. The same is true for digital but can be checked immediately in the field.
The recommendation is that you frequently check your settings and that you go back through your last few shots to ensure that there is nothing amiss.
I shoot in Raw format on my Nikon, which gives me the ability to 'correct' many exposure issues in the office.
That’s ok at one level, but whilst light issues can be addressed to some degree, focusing problems cannot. If your image is out of focus, then no amount of playing with the clarity or sharpness options in Adobe Lightroom is going to rectify this. I know, I have tried.
Again, this problem can be avoided by regularly checking your focusing settings at each new locality if not more often. Be aware that on some cameras it can be very easy to accidentally switch off auto-focus, or vibration compensation systems on lenses.
Another way of mitigating the focusing problem is by stopping down the aperture to increase the depth of field (those parts of your image that are in focus). With most new digital cameras, you can stop down even in dark, overcast settings by simultaneously increasing the ISO. With film, high ISOs were equated with an increase in the graininess of the final result. This is far less of an issue with digital.
7. Make notes and sketches
Sketching an outcrop is an essential skill for field geologists and has not been eliminated by digital photography, no more than it was by film.
Even the most basic sketch allows you to record what you have photographed, and to record locality and measurement information (azimuth, dimensions) as well as key features that you can observe in the field, annotations to help your memory once you are back in the office, and also any questions you have about the outcrop.
Given that with digital you can take a large number of images for any outcrop, it is important to ensure that you remember what you photographed, and this is where an annotated sketch will help (more on field sketching in a few weeks).
Another tip here is to use graphics or presentation software to create an annotated version of your photographs. These are then useful for presentations.
n this example from one of my own presentations, the panorama field photo is annotated with some key observations that I want to draw attention to and then related to the outcrops position stratigraphic chart using some animated graphics. In this case, the position is shown both temporally and spatially. If you are asked to give a presentation with limited time to prepare this sort of slide is relatively quick to produce. The stratigraphy is from a paper downloaded from the internet (in this case the excellent Ph.D. thesis of Elisabet Amorós, 2013) and the panorama can be generated at the outcrop. In MS Powerpoint the annotation and animation take 5-10 minutes depending on what you want to highlight.
8. Be organized
Ensure that once you are home you upload your images immediately and that you tag your pictures whilst they are fresh in your mind. (ideally, you should do this each evening when you are in the field).
If you leave it a week it will be too late, and likely you will never do it.
Tags are useful because they are attributed to each picture in your processing software as metadata and will allow you to search your photo libraries for location, subject, data etc., depending on what keyword system you use.
Adobe Lightroom will, by default, organize your photographs by date, which is still my preferred management scheme.
9. Use post-production to enhance your image library
Post-production in this definition means what happens after you have taken the photograph. With digital, you have much greater flexibility to correct or enhance images to show key features using post-production software, of which there is a range of options. I use Adobe Lightroom.
Whilst these tools are extremely useful, they do take time. So, unless you have unlimited time available, then you will need to be choosey about which images you process. This is about cropping photos for particular tasks or changing the light balance.
Post-production is a subject in its own right, but a couple of key things to think about:
10. Backup your pictures
As with anything on your computer, ensure that you make backups. Storage space is relatively cheap. Losing your photographs is forever.
I had an interesting discussion with a colleague a few years back who was very concerned at how vulnerable’ digital pictures were to loss. The threat of hard-drive failure, viruses, attacks on the cloud, etc. The reply was easy (1) back-ups (2) having one copy of a slide is much, much more vulnerable, and film can deteriorate with time (mildew for one)
My personal recommendation is that you have two backups on physical hard drives. This may sound like overkill but hard-drives do fail. SSDs (solid state drives) should be more resilient but the storage costs of SSD are currently incredibly high in comparison with traditional spinning patter technologies. I would also recommend using a cloud solution such as Dropbox, iCloud or oneDrive.
And make sure that one of these backups is off-site...
This blog is co-posted on the Knowing Earth website (www.knowing.earth)
Paleogeographic maps come in a variety of forms. But it is as reconstructions of past landscapes that they are the most useful. Why? Because it is on these landscapes that the geological record is built. A particle sees topography, rivers, and oceans. It experiences rain and floods and the heat from the sun. It does not see mantle convection nor crustal hyper-extension nor differentiate between a compressional or extensional tectonic setting, at least not directly. How sediment is formed in the hinterland through weathering and erosion, transported and ultimately deposited is a function of what happens at the surface and therefore what that landscape is.
A Google search for the term "paleogeography" reveals a wide range of maps and images. From simple black and white sketches showing past shorelines to maps of depositional systems or the distribution of tectonic plates, to full-color renditions of paleo-elevation and -bathymetry. Many, if not most, are informative, some are aesthetically quite beautiful.
For most geologists, such maps need little introduction. They have a long history of usage in the literature, and today have become something approaching de rigueur for conference presentations and corporate montages.
But paleogeography is more than just images in presentations. It is or can be, a powerful tool for managing, analyzing and visualizing geological information, for investigating the juxtaposition and interaction of Earth processes, as well as acting as the boundary conditions for more advanced Earth system modeling with which to better understand how our planet works.
Over the next few months, I will present a series of blogs that will explore paleogeography.
It will be a journey that will take us through the history of paleogeography, a look at how maps are generated, a guide to some of the pitfalls and caveats of mapping, a review of some of the mapping tools available, as well as examples of how paleogeographic maps have been used to solve real-world problems, especially in resource exploration where I have the most experience.
It is a journey that I hope you enjoy and find useful.
In this first blog, I want to set the scene by addressing two simple questions. What is paleogeography? And why should you care?
The Nature of the Problem: there is simply so much to take in.
If we look at any landscape and the processes responsible for forming it and which are acting on it, such as in the central Pyrenees shown above, we are faced with something of a dilemma: There is simply so much to take in.
For example, if we are teaching field geology in such an area do we focus on the structural evolution, or the stratigraphy, or the depositional systems or the climate, or vegetation or any one of the many components that together comprise the Geological record and the Earth system in this view?
Or do we try and cover all the bases?
Ideally, we want to try and cover everything. But we have limited time. We also do not want to overwhelm all concerned with diverse technical vocabulary and concepts. The risk of losing our audience.
Consequently, we usually focus on a specific field of study.
The same is true in exploration. Whether we are assisting management to make strategic decisions about where to explore or are a member of an asset team identifying and evaluating blocks and then prospects. We need to understand all the components of the Earth system if we are to make informed decisions.
30 years ago, companies would have had an army of in-house specialists on whom they could call for help to do this, and even more academic experts on retainers. But, those days have long since gone.
Unfortunately, one thing that has not gone is the budget constraints of the commercial world.
Exploration is, by its very nature, a net cost to an energy exploration business.
So, in addition to the scientific challenges, in exploration, we are also faced with trying to extract the maximum value from limited budgets.
So, what do we do?
Finding solutions: Paleogeography as a key tool in the geologist’s toolbox
We need a tool with which we can bring together (gather), manage, visualize and interrogate diverse geological information, information which is often sparse (especially in frontier exploration areas), sometimes questionable, and often equivocal.
If we look to history for guidance, we find 19th-century geologists faced with the same problem. A growing volume of diverse geological information and how to deal with it.
Over the preceding 100 years, scientists had tried to encapsulate the contemporary knowledge of the Earth system into a single book or series of books. Humboldt's Cosmos or Lyell's Principles are examples. But this had become next to impossible by the middle of the 19th century due to the sheer volume of information, resulting in an exacerbation of the scientific specialism that we have today. Humboldt’s opus itself was unfinished at his death and completed based on his notes.
One solution to this problem was to use maps to distil visually this wealth of information. Ami Boué’s maps of the World, more commonly known through Alexander Keith Johnston's “Physical Atlas of Natural Phenomena” (Johnston, 1856) in the middle of the century., or Élisée Reclus’ excellent “The Earth” (Reclus, 1876)
Reclus’s book on the Earth (Reclus, 1876) included maps showing the distribution of mountains and volcanoes. With the distribution of seismicity and you have all the information necessary for plate tectonics.
With geology, the problem was exacerbated by the time dimension. This was not simply a matter of mapping the current physical state of the Earth and its processes but how this had evolved over time. The past geography of the Earth. This is Paleogeography.
It is no coincidence that Thomas Sterry Hunt, the author attributed with first coining the term “paleogeography”, was also one of the first petroleum geologists, looking for ways to manage and analyze geological data for exploration. (We will revisit this in a later blog).
Paleogeographic maps can summarise a wealth of geological information in a simple, visual way by distilling the record into representations of depositional environments and structures. This then allows additional information to be added and juxtapositions and relationships investigated.
Such maps can also show lithological distribution and character, although strictly speaking facies maps are distinct from paleogeography’s in that they represent the product of processes, i.e. the rock record (as do GDEs for that matter), whilst a paleogeography represents the environment and landscape in which and on which those processes act and upon which the geological record is built.
The late Ypresian paleogeography for the central Pyrenees showing one transport pathway that takes in the three outcrops shown. From Markwick (2019)
In practice, this definition of paleogeography has become blurred. Facies maps, GDEs (Gross Depositional Environments), and plate reconstructions are all frequently referred to as “paleogeography”.
The original definition of paleogeography proposed by Hunt was as a field within geology to describe the “geographical history” of the geological record, which to him included the depositional environments, such as deserts and seas (Hunt, 1873).
This view of paleogeography as being the representation of the depositional environments that comprise a landscape is useful for two important reasons.
First, because it allows us to distinguish between the landscape, the processes acting on the landscape, the processes that created the landscape, and the rock record that is the product of all of the above. This makes the Earth system more manageable. It also means that when building a map we can audit each step (something we will look at another time).
But second, it allows us to deconstruct what the rock record directly responds to. What is important to consider. Where we need to focus our time (and monies). If we think of a sedimentary particle formed in the hinterland through weathering and erosion, transported and ultimately deposited, what does it really ‘see’ (i.e. respond to – at the risk of personifying clastic particles too much). A particle sees topography, rivers, and oceans. It experiences rain and floods and the heat from the sun. It does not see mantle convection nor crustal hyper-extension nor differentiate between a compressional or extensional tectonic setting, at least not directly.
It responds to the contemporary landscape and the processes acting on it.
A particle eroded from the hinterland and transported to its depositional location responds on its journey to processes at the Earth surface
Paleogeography defined: the problem of time
We now need to add another component to our definition of what paleogeography is. And that is time.
This is something that was identified by Charles Schuchert, a professor at Yale and colleague of Joseph Barrell, one of the founders of modern stratigraphy.
Cenomanian – Turonian section, Steinaker Reservoir. What would a Cretaceous paleogeography meaningfully represent? The transgressive shales or prograding sands or any range of other units through the Cretaceous
The Earth is dynamic and landscapes and depositional environments and their products the rock record can change over relatively limited geographic distances and short temporal intervals. For Schuchert, a global Cretaceous map was meaningless, for the very simple reason of what exactly did it represent? A landscape at the beginning of the Cretaceous, the end, the maximum extent of marine conditions, or as more likely, a pastiche of lots of different parts of that Cretaceous record? Schuchert’s recommendation was to use the finest stratigraphic intervals possible, which for him were represented by stratigraphic formations.
Kay went further to suggest that ideally paleogeography should represent a “moment in time”. Rather like looking at a satellite image. In this definition, paleogeography was a snapshot of the depositional environment and the landscapes at a specific moment. That makes perfect sense, but there is a problem. In the absence of a global correlation tool that can pick out a moment in time, this is next to impossible to achieve, especially over large distances. But it is an aspiration. It is also a reminder to ask of a map, what does it represent? Again, this is something we will return to in a later blog.
What is paleogeography?
Paleogeography is the representation of the past surface of the Earth, at a ‘moment’ in time.
Why is it important and why should you care?
Because it allows us to bring together diverse information that will help us better understand the Earth system, whether we are teaching in Spain or faced with deciding on where to explore. Paleogeography gives us the spatial context for gathering, managing, visualizing and analyzing a wide array of geological information in a way that is easy to digest.
At the end of the day, paleogeography is far more than just an image in a presentation.
Maastrichtian paleogeography showing the distribution of DSDP and ODP sites (small red circles) and vertebrates (Markwick and Valdes, 2004; Markwick, 2007)
This blog is one of a series based on a lecture course on paleogeography. Readers are also directed to a new paper on paleogeography published in the Geological Magazine: https://www.cambridge.org/core/journals/geological-magazine/article/palaeogeography-in-exploration/444CC2544340A699A01539A2D4C6E92A
Hunt, T. S., 1873, The paleogeography of the North-American continent: Journal of the American Geographical Society of New York, v. 4, p. 416-431.
Johnston, A. K., 1856, The physical atlas of natural phenomena, London, William Blackwood & Sons, 137 p.:
Markwick, P. J., 2007, The palaeogeographic and palaeoclimatic significance of climate proxies for data-model comparisons, in Williams, M., Haywood, A. M., Gregory, F. J., and Schmidt, D. N., eds., Deep-time perspectives on climate change: London, The Micropalaeontological Society & The Geological Society of London, p. 251-312.
Markwick, P. J., 2019, Palaeogeography in exploration: Geological Magazine (London), v. 156, no. 2, p. 366-407.
Markwick, P. J., and Valdes, P. J., 2004, Palaeo-digital elevation models for use as boundary conditions in coupled ocean-atmosphere GCM experiments: a Maastrichtian (late Cretaceous) example: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 213, p. 37-63.
Reclus, É., 1876, The Earth. A descriptive history of the phenomena of the life of the Globe, Leicester Square, London, Bickers and Son.
Paleogeographic maps are common throughout the Earth sciences. There seem to be few geological presentations today, in either Academia or Industry, that do not include at least one paleogeography, some of which have become aesthetically quite beautiful. But, despite this, the full power of paleogeography as a tool in geological problem solving remains underutilized. In many, if not most cases, maps are used simply as a backdrop image for locating data. That is a great shame.
When Thomas Sterry Hunt first coined the phrase 'paleogeography' in 1873 (Hunt, 1873), it was not just as a 'pretty' picture for a presentation, but as a way to bring together diverse geological information to better understand the Earth system.
Hunt was one of the first petroleum geologists, and by the time of his paper, he was faced with the problem of a rapidly expanding library of geological observations and ideas that needed to be managed. A situation that is all the more applicable today.
Earlier geologists had used land-sea maps as one means of managing and visualizing this wealth of information. But, it was Hunt who applied these maps to exploration and who established the first systematic workflow for building paleogeography by stressing the importance of the underlying crustal architecture. This workflow was expanded and developed by Charles Schuchert in the early 20th century (Schuchert, 1910, 1928) and later by Fred Ziegler (Ziegler et al., 1985) and the Paleogeographic Atlas Project (the subjects of future blogs).
Paleogeography has long been a passion with me ever since I was an intern at BP’s research center in Sunbury-on-Thames back in the mid-1980s. The first atlases of global plate reconstructions had been published 10 years before (Briden et al., 1974; Smith and Briden, 1977; Smith et al., 1973) and by the 1980s were becoming much more widely used. In Chicago, Fred Ziegler’s Paleogeographic Atlas Project was developing new methods for mapping and applying the results directly to exploration problems (Ziegler et al., 1985), including the use of paleogeography with paleoclimatology to retrodict (predict the past state) the distribution of source rocks. This had demonstrated to the oil and gas exploration industry that there might be a better and cheaper way to do preliminary basin screening.
This is where I came into the story, working on paleogeographic maps, paleoclimatology, source rock databases, and retrodictions. It was a great time with so many new developments and ideas about the Earth.
Many groups have developed paleogeographies over the years. Too many to mention in one blog or paper. One could mention the influential atlases of Peter Ziegler at Shell (Ziegler, 1982), the ground-breaking Russian atlases of Vinogradov (1968, 1969; 1967; 1968) and then Ronov (1989; 1984) and their teams in Moscow, the coastline maps of Smith et al., at Cambridge (and BP) (Smith and Briden, 1977; Smith et al., 1994); the maps of Dore in Statoil (Doré, 1989), and Dércourt in France (Dercourt et al., 1993), and more recently the excellent work by the University of Rennes research group of Francois Guillocheau (Chaboureau et al., 2013). Not forgetting, of course, the highly influential and widely used maps of Chris Scotese (Scotese, 2008; Scotese et al., 1979; Scotese and Golonka, 1992), who has perhaps done more than most geologists to promote plate reconstructions and paleogeography. It was on Chris’s maps that Ron Blakey from Arizona first generated his beautiful 'Photoshopped' maps which many of you have seen and probably used.
But, for me, it was the developments by what I refer to as the 'Chicago School' that were the most influential, especially in the exploration Industry. It was at Chicago that Chris Scotese published his initial work as a post-doc of Fred's, where Dave Rowley and Ann Lottes published a series of papers on plate modeling, and where many of Fred’s students, including Mike Hulver (now at Saudi Aramco), myself (Markwick and Valdes, 2004) and others learned and developed our understanding of geology and paleogeography, as well as methodologies for data management, auditing, and visualization.
The Paleogeographic Atlas Project is important to the story of paleogeography and its applications in two principal ways:
1. The reconstruction of paleolandscapes, not just depositional systems or facies.
2. Data management, data verification, and auditing and digital databasing, building on the ideas of earlier workers such as Schuchert (1910) and Kay (1945)
Paleolandscapes are key because at the end of the day this is what the rock record sees. A particle weathered from the highlands in the hinterland of a basin, does not see mantle anomalies, or hyper-extended crust, at least not directly. It sees the vegetation, rivers, lakes, and sea. It sees the surface of the Earth, which is the landscape.
Data management, because without an audit trail how do you know how good the maps are? This was and is critical for the exploration industry with their need to understand exploration risk, in order to make informed decisions. Decisions that have a financial cost.
The Paleogeography Atlas Project was sponsored by the oil and gas industry and so these questions and drivers were foremost in Fred's mind. It was also this link with the Industry that stimulated the work of Judy Parrish in the early 1980s and her seminal publications on source rock retrodiction using early parametric paleoclimate models and paleogeography to reconstruct the location of ocean upwelling. These models were subsequently computerized by Scotese and Summerhayes (1986).
Over the last 18 months, I have been revisiting this story.
One result is this paper on “Paleogeography in Exploration” (Markwick, 2018).
This is designed to provide an introduction to the history and methodologies of paleogeography, including the latest version of Hunt’s mapping workflow. Associated with this is a new mapping legend, which is available through the publication as supplemental data, as well as online as digital .style files for use with ESRIs ArcGIS. Three case studies are given which show how paleogeography can be applied at different scales to solve different exploration problems.
There is much more to add to this story and more will follow. But, for now, my aim to get the next generation of geologists, and especially explorationists, thinking about how they can use paleogeography maps more effectively in their workflows. And also, I hope, to get them excited about reconstructing the Earth system, an excitement I first discovered back in BP in the mid-1980s.
At the very least I hope that readers will see that paleogeography is so much more than just a flat image, beautiful that these may be.
"Palaeogeography in Exploration" was published online in June 2018 in the Geological Magazine and will be published as part of the “Advances in Palaeogeography” volume in early 2019.
I wish to thank the volume editor, Guido Meinhold, for all his hard work in putting together a very interesting collection of papers on this important topic and for his kind inclusion of my research. I am also indebted to the reviewers, especially Tony Doré, for their perseverance in reading the original draft, which as they described it, read “more like a book…” The final version greatly benefited from their suggested changes and their dedication to the review process. They will be relieved to hear that the final version is considerably shortened. A book will be out shortly.
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