Posted on 10/22/2009 3:06:22 PM PDT by decimon
Thirty million years ago, before Ethiopia's mountainous highlands split and the Great Rift Valley formed, the tropical zone had warmer soil temperatures, higher rainfall and different atmospheric circulation patterns than it does today, according to new research of fossil soils found in the central African nation.
Neil J. Tabor, associate professor of Earth Sciences at SMU and an expert in sedimentology and isotope geochemistry, calculated past climate using oxygen and hydrogen isotopes in minerals from fossil soils discovered in the highlands of northwest Ethiopia. The highlands represent the bulk of the mountains on the African continent.
Tabor's research supplies a picture of the paleo landscape of Ethiopia that wasn't previously known because the fossil record for the tropics has not been well established. The fossils were discovered in the grass-covered agricultural region known as Chilga, which was a forest in prehistoric times. Tabor's research looked at soil fossils dating from 26.7 million to 32 million years ago.
Fossil plants and vertebrates in the Chilga Beds date from 26.7 million to 28.1 million years ago, Tabor says. From his examination, Tabor determined there was a lower and older layer of coal and underclay that was a poorly drained, swampy landscape dissected by well-drained Oxisol-forming uplands. A younger upper layer of the Chilga Beds consists of mudstones and sandstones in what was an open landscape dominated by braided, meandering fluvial stream systems.
Tabor is part of a multi-disciplinary team combining independent lines of evidence from various fossil and geochemical sources to reconstruct the prehistoric climate, landscape and ecosystems of Ethiopia, as well as Africa.
The project is funded with a three-year, $322,000 grant from the National Science Foundation. The team includes paleoanthropologists, paleobotanists and vertebrate paleontologists from the University of Texas at Austin, Miami University, Southern Methodist University, the Fort Worth Museum of Science and History, Washington University and the University of Michigan.
Tabor presented the research in a topical session at the Oct. 18-21 annual meeting of the Geological Society of America. The presentation was titled "Paleoenvironments of Upper Oligocene Strata, NW Ethiopian Plateau." His co-researcher is John W. Kappelman, Department of Anthropology, University of Texas. — Margaret Allen
Related links: SMU Research: Ethiopian fossils define prehistoric ecosystems, human evolution, climate change Ethiopia project home page Neil J. Tabor Why fossils matter SMU Student Adventures blog: Research team in Ethiopia, 2007-2008 Roy M. Huffington Department of Earth Sciences Dedman College of Humanities and Sciences
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Thanks decimon. |
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And, apparently, lots more SUVs.
Obviously the rampant irresponsible release of carbon by SUV drivers 27 million years ago/before present caused this and we need a bailout for Ethiopia and a tax increase all of which is Bush’s fault.
...and probably higher I.Q.s in it's population, than the reprobates that are running this country at the moment.
5.56mm
Gotta be.
Shhhh... you might be accused of being a scientist or a DUer or someone who uses sources other than Sean Hannity.
Do you know which correction(s) they applied?
Corrections?
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