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.
"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.
www.geosociety.org/science/timescale/timescl.pdf
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