3 posts were split to a new topic: Side Comments on : Petroleum geology predictions
It takes time to deposit the sediments that eventually wil generate hydrocarbons, reservoirs and cap rocks. It takes time to deform strata to create traps and it takes time for hydrocarbons to migrate from their source area into the reservoirs
My layman’s understanding is that the time required is a matter of physics. Eg, the “mud problem” is about how long it takes for a given thickness of mud to solidify. Based on the physics that working engineers use in real projects today, very thick layers would need much longer times than YEC can allow. So any YEC model for oil exploration would need to posit different physics at work (and explain that change) or appeal to a miracle. The miracle itself would need a theological explanation - see The Burning Bush Reversed: the Unbiblical Miracles of Young Earth Creationism.
@faded_Glory can you elaborate on some of the ways that oil and gas models require long periods of time? Edit: Whoops, you actually did elaborate before this post got approved. Thanks!
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@faded_Glory This is all super interesting, thanks so much for explaining.
A basin in the geological sense is a confined geographical area where significant thicknesses of sediments have been deposited over time. Such basins are often very favourable for oil and gas accumulation because many of the critical elements are present, such as source, reservoir and cap rocks. Basins are formed by subsidence of the Earth crust over time, generating space for large volumes of sediment to accumulate, often derived from erosion of surrounding land masses but also from more local formation of biogenic calcareous sediments.
Ooh, I’ve imagined animated 3D models showing areas of deposition and erosion changing as the landscape and/or sea level rises and falls over time. I bet those are fascinating to see.
It is of no use if the source rock goes through the oil and gas window before the reservoir rocks have been deformed into the structures that can trap hydrocarbons.
In that case, do they just “leak out” onto the surface and dissapate?
Also, going back to something you said earlier:
due to the highly competitive nature of the industry a great amount of data and models reside in corporate archives and will only very slowly be released into the public domain
I read a claim somewhere that the industry has records of multiple basins on earth where the entire geologic column has been found in one place. I wonder if you have any knowledge of that?
Me too. My (crashed) dissertation project involved so hydrologic modeling, and I 've always dreamed of adding geologic modeling to that. It’s probably not feasible in the way I think of it, but it sure is fum to think about.
Not all in one place, I think, but long overlapping sections in separate basins that can be used to construct a complete record, Also multiple basins that allow the constructions to be verified.
3D Basin Models (actually, 4D!) are quite common nowadays but don’t expect to see a lot of what happened near the surface. The emphasis is very much on the deeper subsurface because that is where the hydrocarbons are generated and currently reside. Usually the models have a flat sea level as their baseline. The only surface feature of direct interest would be sea level rise and fall because that impacts the pressure distribution in the subsurface, a factor relevant for hydrocarbon generation, and pressure will usually also have an effect on reservoir rock properties. Too high overburden pressure and the porosity of the reservoir will decrease and ultimately be completely destroyed.
To answer your other question, hydrocarbons are lighter than formation water and will migrate up towards the surface unless stopped by a trap. If the traps aren’t there when the migration occurs it will simply escape to the surface. Numerous seeps of oil and gas found all over the world illustrate this nicely.
I don’t have personal experience of a basin where the entire geological column is present. The earth is a very dynamic environment where vertical crustal movements take place in most places most of the time. On the one hand this can create vertical space for sedimentary basins, but on the other hand this means that a lot of rock previously laid down at times gets uplifted, exposed and eroded away again. So, generally there are missing sections. As Dan_Eastwood said, we can usually work around this by correlating between wells to identify sections missing in one well as being present in another. Of course this usually requires accurate determination of the times of deposition, something that YEC is incapable of (after all these years they still haven’t reached basic agreement on what are pre, syn and post flood rocks).
Another limiting factor pertinent to the industry is that we usually stop drilling when we reach basement, either crystalline rocks that generally are non-reservoirs (with a few rare exceptions) or sediments buried so deep that all porosity has been destroyed so they are no longer capable of hosting or producing hydrocarbons. Technological advances and depletion of shallower reservoir have meant that nowadays ever deeper wells are being drilled, over 8000 m is no longer exceptional. However, if you know that basins can often contain over 10 km. of sediment, with the thickest being the Bengal Fan that contains a sedimentary pile of 20 km thick, it is clear that we haven’t sampled everything, and are unlikely to do so.
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My niece, the geologist, studied sand dune formation and shapes, as these “sandstone lenses” are where oil and gas tend to get trapped.
That’s pretty cool. I did some surface water modeling on a much smaller scale. And LOL - because that article has only self-citations, We had already figured out the results would be largely irrelevant before it was published, but that’s what they paid us to do. 
Remember, there are multiple types of “geological columns”.
Consider a chronostratigraphic column versus a lithostratigraphic column. A chronostratigraphic column is organized along the time periods of the units, while a lithostratigraphic column is organized by rock types.
A chronostratigraphic column is kind of like a desk calendar, where we jot in notes about what we did on each day. Every personal calendar has the same days, weeks, months, etc but each will record very different events on each day. The geological periods (Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian for example) are the same in any part of the world, but the rocks and events in each period (lithology) can be very different in different places.
So a chronostratigraphic column can indeed be “complete” anywhere in the world, but specific rocks may or not be present. There are some locations where some rocks of each Paleozoic period are present, but even then there are unconformities (missing layers) in each period.
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Cool! I’ve worked Jurassic dune sands (Entrada Formation in the San Juan Basin) for both O&G prospects and for acid gas disposal wells.
The Entrada sands are typically covered by carbonates and gypsum (Wanaka and Todilto formations), which form excellent cap rocks.
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