Sunday, January 18, 2015

Rant on fossil fuel age inaccuracies on the web!

In the last couple weeks, I have found a few websites with gross inaccuracies about the geologic age of fossil fuel resources. I was disappointed, but just rolling my eyes, after the first finds one day, mostly because they were not science websites. But the second incident pushed me over the threshold of frustration, partly because it was the second occurrence in so many weeks and partly because it was on a state government energy education webpage.

The first were on various Pennsylvania anthracite region websites, including http://www.blaschakcoal.com/wp-content/uploads/Anthracite-Advantage-Fact-Sheet1.pdf and http://huberbreaker.org/home/history/history-of-anthracite-region/. Blaschak is an anthracite coal producer in northeastern Pennsylvania (PA), USA. Although I found their fact sheet through Google, I cannot find it from within the Blaschak website, a well-done website that describes the current mining practices, reclamation, and coal quality data. On the fact sheet, however, they state "Today, anthracite is the oldest, hardest and cleanest type of coal". The Huber Breaker historical site also calls anthracite the oldest type of coal ("that is, it took nature the longest to form"). About.com (http://energy.about.com/od/Coal/a/Anthracite-Coal.htm) writes
"Anthracite is mined from the oldest geological formations, and therefore has spent the longest time underground and been subjected to the most pressure and heat, making it the most compressed and hardest coal. Hard coals contain greater potential to produce heat energy than do the softer, geologically 'newer' coals." Yikes!

In fact, in Pennsylvania, the rock formations of both the anthracite coals (eastern PA in Valley and Ridge physiographic province) and bituminous coals (western PA in Allegheny Plateau province) are time equivalents (p. 21 [page 2 of .pdf]: https://www.dep.state.pa.us/dep/deputate/minres/bmr/beneficial_use/10%20CHAPT%202/Chapter%202%20final.pdf). The higher rank of PA anthracite is due to increased deformation and probably advective (heated) groundwater flow (Harrison, M. J., Marshak, S., and Onasch, C. M., 2004, Stratigraphic control of hot fluids on anthracitization, Lackawanna synclinorium, Pennsylvania: Tectonophysics, v. 378, p. 85-103). The coals were deposited during the Pennsylvanian subperiod (323-299 Ma*) of the Carboniferous Period. The folding and thrusting that created the Valley and Ridge province occurred during the late Paleozoic Alleghanian orogeny, but was west of the most intense deformation and metamorphism in the Piedmont.

More concerning is information in the fossil fuel chapter of the award-winning "Energy Quest" education pages (http://energyquest.ca.gov/about.html) of the California Energy Commission (http://www.energyquest.ca.gov/story/chapter08.html). The page says 
    "There are three major forms of fossil fuels: coal, oil and natural gas. All three were formed many hundreds of millions of years ago before the time of the dinosaurs – hence the name fossil fuels. The age they were formed is called the Carboniferous Period. It was part of the Paleozoic Era. "Carboniferous" gets its name from carbon, the basic element in coal and other fossil fuels. . . . Some deposits of coal can be found during the time of the dinosaurs. For example, thin carbon layers can be found during the late Cretaceous Period (65 million years ago) – the time of Tyrannosaurus Rex. But the main deposits of fossil fuels are from the Carboniferous Period."

This is very incorrect! The major coal deposits of western Europe and the eastern US are indeed Carboniferous in age. BUT, world-wide there are coals as old as Devonian, and peats and soft brown coals as young as Pleistocene (epoch of recent Ice Ages). Texas and North Dakota lignites (western US) are Paleogene (just after dinosaurs); "Gondwanan" coals of India, Australia, Antarctica and Africa are Permian (Taylor, G. H., Teichmüller, M., Davis, A., Diessel, C. F. K., Littke, R., Robert, P., 1998, Organic petrology: Gebrüder Borntraeger, Berlin, 704 pages) (see also Geologic Time Scale link at bottom). Petroleum (liquid or gas) has been found in 1 billion year old rocks (thinking of the Nonesuch Formation, White Pine, MI); California's most hydrocarbon-prolific formation is the much younger Miocene Monterey Formation, whose age ranges from 15-4 Ma (http://archives.datapages.com/data/pac_sepm/030/030001/pdfs/87.htm).

I have no idea where these webpage authors got their information! In a deep basin where sediments are sequentially buried by younger and younger rocks, organic matter in the older rocks would be more indurated or metamorphosed. But those discussing anthracite seemed to have gone backwards and assumed that higher coal rank means older, without looking up the actual age of the anthracite coals compared to the bituminous ones on the other side of the state: it is other factors like maximum burial depth, deformation and tectonics that caused the difference in PA coal rank.

The California energy page information is even more disappointing, given the excellent resources right there in state: the California Geological Survey, state public and private universities, and the oil industry itself. I found the webpages because a technology education teacher acquaintance uses them as source information for students on types of conventional and alternative energy. I did send the Energy Quest media contact an e-mail describing the inaccuracy and suggesting (hoping) they contact either the state survey or a university geology department to get their geology information in order.

*Ma= million years ago; Here is a link to the geologic time scale:
www.geosociety.org/science/timescale/timescl.pdf

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