Wednesday, August 20, 2014

Geology Sonnet 2

As mentioned previously, I am writing Geology Sonnets for National Science Week.  These are articles from the high-profile scientific journal Geology, presented in the form of Elizabethan verse. I don’t know how many of these I will get through this week, but here is the second:

The Central Atlantic Magmatic Province
Erupted tholeiitic and potassic.
C O two upset atmospheric balance.
Eco-collapse ended the Triassic.
Green sulfur bacteria’s isotopes
Show photic zone euxinia prevailed.
Stomatal size decreased (show microscopes)
And carbon biomass was soon curtailed.
Compound-specific isotopes will tell
Which phytoplankton thrived in these tough times,
While wax from leaves and calcite from a shell
Record recovery in clastic slimes.
The Triassic ended as it began.
Can those extinctions be surpassed by man?

Caroline M.B. Jaraula, Kliti Grice, Richard J. Twitchett, Michael E. Böttcher, Pierre LeMetayer, Apratim G. Dastidar and L. Felipe Opazo. (2013) Elevated pCO2 leading to Late Triassic extinction, persistent photic zone euxinia, and rising sea levels. Geology 41 955-958.


The Late Triassic mass extinction event is the most severe global warming–related crisis to have affected important extant marine groups such as scleractinian corals, and offers potential insights into climate change scenarios. Here we present evidence from Chlorobi-derived biomarkers of episodic and persistent photic zone euxinia. From biomarkers and stable carbon isotopes, we present evidence of rapid mixing of atmospheric and oceanic carbon reservoirs. Global versus regional trends are resolved in kerogen organic matter type, carbonate δ13C, and bulk and pyrite δ34S. This suite of data demonstrates for the first time a comprehensive organic and stable isotope geochemical reconstruction of events leading up to the Late Triassic extinction event and its aftermath. The cascade of events prior to, during, and after the extinction is remarkably similar to those reported for the Late Permian extinction, the largest extinction event of the Phanerozoic. We predict that similar conditions will have occurred during all past episodes of rapid global warming and biotic crisis that are associated with similar rises in pCO2.

Other geosonnets: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28

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