Free Republic
Browse · Search
General/Chat
Topics · Post Article

Skip to comments.

Central Africa's tropical Congo Basin was arid, treeless in Late Jurassic
Southern Methodist University ^ | Nov 10, 2009 | Unknown

Posted on 11/10/2009 3:23:21 PM PST by decimon

Geochemical analysis of rare ancient soil produces new paleoclimate data

The Congo Basin — with its massive, lush tropical rain forest — was far different 150 million to 200 million years ago. At that time Africa and South America were part of the single continent Gondwana. The Congo Basin was arid, with a small amount of seasonal rainfall, and few bushes or trees populated the landscape, according to a new geochemical analysis of rare ancient soils.

The geochemical analysis provides new data for the Jurassic period, when very little is known about Central Africa's paleoclimate, says Timothy S. Myers, a paleontology doctoral student in the Roy M. Huffington Department of Earth Sciences at Southern Methodist University in Dallas.

"There aren't a whole lot of terrestrial deposits from that time period preserved in Central Africa," Myers says. "Scientists have been looking at Africa's paleoclimate for some time, but data from this time period is unique."

There are several reasons for the scarcity of deposits: Ongoing armed conflict makes it difficult and challenging to retrieve them; and the thick vegetation, a humid climate and continual erosion prevent the preservation of ancient deposits, which would safeguard clues to Africa's paleoclimate.

Myers' research is based on a core sample drilled by a syndicate interested in the oil and mineral deposits in the Congo Basin. Myers accessed the sample — drilled from a depth of more than 2 kilometers — from the Royal Museum for Central Africa in Tervuren, Belgium, where it is housed. With the permission of the museum, he analyzed pieces of the core at the SMU Huffington Department of Earth Sciences Isotope Laboratory.

"I would love to look at an outcrop in the Congo," Myers says, "but I was happy to be able to do this."

The Samba borehole, as it's known, was drilled near the center of the Congo Basin. The Congo Basin today is a closed canopy tropical forest — the world's second largest after the Amazon. It's home to elephants, great apes, many species of birds and mammals, as well as the Congo River. Myers' results are consistent with data from other low paleolatitude, continental, Upper Jurassic deposits in Africa and with regional projections of paleoclimate generated by general circulation models, he says.

"It provides a good context for the vertebrate fossils found in Central Africa," Myers says. "At times, any indications of the paleoclimate are listed as an afterthought, because climate is more abstract. But it's important because it yields data about the ecological conditions. Climate determines the plant communities, and not just how many, but also the diversity of plants."

While there was no evidence of terrestrial vertebrates in the deposits that Myers studied, dinosaurs were present in Africa at the same time. Their fossils appear in places that were once closer to the coast, he says, and probably wetter and more hospitable.

The Belgium samples yielded good evidence of the paleoclimate. Myers found minerals indicative of an extremely arid climate typical of a marshy, saline environment. With the Congo Basin at the center of Gondwana, humid marine air from the coasts would have lost much of its moisture content by the time it reached the interior of the massive continent.

"There probably wouldn't have been a whole lot of trees; more scrubby kinds of plants," Myers says.

The clay minerals that form in soils have an isotopic composition related to that of the local rainfall and shallow groundwater. The difference in isotopic composition between these waters and the clay minerals is a function of surface temperature, he says. By measuring the oxygen and hydrogen isotopic values of the clays in the soils, researchers can estimate the temperature at which the clays formed. For more information see www.smuresearch.com.

###

Myers presented his research, "Late Jurassic Paleoclimate of Central Africa," at a scientific session of the 2009 annual meeting of The Geological Society of America in Portland, Ore., Oct. 18-21.

The research was funded by the Roy M. Huffington Department of Earth Sciences at SMU, and the Institute for the Study of Earth and Man at SMU.

SMU: A private university located in the heart of Dallas, SMU is building on the vision of its founders, who imagined a distinguished center for learning emerging from the spirit of the city. Today, nearly 11,000 students benefit from the national opportunities and international reach afforded by the quality of SMU's seven degree-granting schools.


TOPICS: History
KEYWORDS: godsgravesglyphs; gottacongomaydastona

1 posted on 11/10/2009 3:23:23 PM PST by decimon
[ Post Reply | Private Reply | View Replies]

To: SunkenCiv

Bushes fault ping.


2 posted on 11/10/2009 3:24:06 PM PST by decimon
[ Post Reply | Private Reply | To 1 | View Replies]

To: decimon
Then the Ugandans began to drive their Southern Ugandan Vehicles and the Warming and Rains came.
3 posted on 11/10/2009 3:26:35 PM PST by Young Werther ("Quae Cum Ita Sunt - Julius Caesar "Since these things are so!")
[ Post Reply | Private Reply | To 1 | View Replies]

To: Young Werther

LOL

Reminded me of this:

http://sophistacat.blogspot.com/2007/04/time-to-act-is-now.html


4 posted on 11/10/2009 3:33:04 PM PST by Famishus (North of the equator, the Death Spiral is clockwise.)
[ Post Reply | Private Reply | To 3 | View Replies]

To: decimon

.....”was far different 150 million to 200 million years ago”.....


5 posted on 11/10/2009 3:41:51 PM PST by cranked
[ Post Reply | Private Reply | To 1 | View Replies]

To: decimon

Well, if it was an arid envionrment that must mean there was some kind of climate-change or global warming going! So what caused that and why isn’t Al Gore all over this!?! Bloody dinosaurs!! That who started global warming! sacrasm)


6 posted on 11/10/2009 3:47:10 PM PST by JoeMac ("Dats all I can stands 'cuz I can't stands no more!'' Popeye The SailorMan)
[ Post Reply | Private Reply | To 1 | View Replies]

To: decimon

Bushosaurus’ fault!


7 posted on 11/10/2009 4:02:20 PM PST by rfp1234
[ Post Reply | Private Reply | To 1 | View Replies]

To: decimon

8 posted on 11/10/2009 4:18:22 PM PST by FroggyTheGremlim
[ Post Reply | Private Reply | To 1 | View Replies]

To: decimon; StayAt HomeMother; Ernest_at_the_Beach; 1ofmanyfree; 21twelve; 24Karet; 2ndDivisionVet; ...

· join list or digest · view topics · view or post blog · bookmark · post a topic · subscribe ·

 
Gods
Graves
Glyphs
Thanks decimon.

To all -- please ping me to other topics which are appropriate for the GGG list.
GGG managers are SunkenCiv, StayAt HomeMother, and Ernest_at_the_Beach
 

·Dogpile · Archaeologica · ArchaeoBlog · Archaeology · Biblical Archaeology Society ·
· Discover · Nat Geographic · Texas AM Anthro News · Yahoo Anthro & Archaeo · Google ·
· The Archaeology Channel · Excerpt, or Link only? · cgk's list of ping lists ·


9 posted on 11/10/2009 4:23:19 PM PST by SunkenCiv (https://secure.freerepublic.com/donate/__Since Jan 3, 2004__Profile updated Monday, January 12, 2009)
[ Post Reply | Private Reply | To 1 | View Replies]

To: eCSMaster
Ripp of the original by Gary Larson.

The Earth is amazingly old, and the same area has experienced different flora and fauna and different climates such that you simply don't find modern angiosperm plants or modern placental mammals in the gullets of our cute cig smoking dinosaurs; or jungle plants when the Congo was arid, etc, etc.

10 posted on 11/10/2009 4:24:10 PM PST by allmendream (Wealth is EARNED not distributed, so how could it be RE-distributed?)
[ Post Reply | Private Reply | To 8 | View Replies]

To: allmendream

You left out the part where large chunks of ground were once underwater and large chunks of the surface that are underwater used to be above ground.

The Earth has been around a long time indeed.


11 posted on 11/10/2009 5:29:38 PM PST by coconutt2000 (NO MORE PEACE FOR OIL!!! DOWN WITH TYRANTS, TERRORISTS, AND TIMIDCRATS!!!! (3-T's For World Peace))
[ Post Reply | Private Reply | To 10 | View Replies]

To: coconutt2000
Yes, and with appropriate marine fossils to the era that you would expect them to be underwater, thus geology and biology supply independent confirmation.
12 posted on 11/10/2009 6:22:45 PM PST by allmendream (Wealth is EARNED not distributed, so how could it be RE-distributed?)
[ Post Reply | Private Reply | To 11 | View Replies]

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
General/Chat
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson