Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists Discover Effects from Rapid, Global Climate and Ocean Changes of the Past

21.03.2003


An international team of marine geologists has just completed an expedition to an area off the coast of Surinam known as the Demerara Rise. The scientists were part of the two-month Leg 207 of the NSF-supported Ocean Drilling Program (ODP) expedition in the equatorial Atlantic Ocean. The project studied periods in Earth’s history that have undergone rapid climate and ocean circulation changes and likely led to mass extinctions of plants and animals.


The National Science Foundation supports the Ocean Drilling Program. Using equipment like the drill pictured here, workers obtain geologic samples from the deep seafloor that provide scientists with new information on Earth’s history. Examples of information documented by these samples include a history of the ocean basins and evidence of drastically changing climates on earth, including more ice ages than were previously known.
Photo Credit: Texas A&M University



Three decades ago, geologists found sediments in the Demerara Rise from the Cretaceous Period (140-65 million years ago) that contained evidence of times when the equatorial Atlantic Ocean was without oxygen. These periods, known as “ocean anoxic events,” indicate that the oceans had a vastly different circulation pattern than they do today.

"Therefore, climate would have been significantly different. We don’t yet fully understand the reasons for these differences," said Jochen Erbacher of the Federal Institute for Geosciences and Natural Resources in Germany. "Our objective [on this cruise] was to re-core the former site to understand past ocean circulation with respect to water depth change."


Scientists also brought up sediment cores that show other periods of dramatic change in Earth’s history. In these sediments are well-preserved intervals of the Cretaceous/Tertiary boundary. At that time, some 65 million years ago, a huge asteroid or comet crashed into the Earth. Scientists believe the resulting cloud of debris may have blocked out sunlight, resulting in the extinction of plants and animals, including dinosaurs.

The Leg 207 team included sedimentologists, stratigraphers, paleontologists, geochemists, engineers, and geophysicists.

"It is only through the integration of all these disciplines that we can begin to understand the causes and effects of these periods of climatic and oceanographic change," said scientist David Mosher of the Geological Survey of Canada. "With a better understanding of what happened in the past, we can perhaps know more about what the Earth is presently enduring," he said.

Adds Paul Dauphin, program director for ODP at NSF, "The research team chose this area for the potentially high-resolution paleoceanographic records that could be recovered [in sediments] for the time intervals of interest, and for the important role that tropical regions play in driving ocean and atmospheric circulation."

ODP is an international partnership of scientists and research institutions organized to study the evolution and structure of the Earth. It is funded principally by NSF, with substantial contributions from international partners.

Cheryl Dybas | NSF

More articles from Earth Sciences:

nachricht Ice cave in Transylvania yields window into region's past
28.04.2017 | National Science Foundation

nachricht Citizen science campaign to aid disaster response
28.04.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>