Mass Mortality and its Environmental and Evolutionary Consequences

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

53

Scientific paper

The latest Mesozoic and earliest Tertiary sediments at Deep Sea Drilling Project site 524 provide an amplified record of environmental and biostratographic changes at the end of Cretaceous. Closely spaced samples, representing time intervals as short as 102 or 103 years, were analyzed for their bulk carbonate and trace-metal compositions, and for oxygen and carbon isotopic compositions. The data indicate that at the end of Cretaceous, when a high proportion of the ocean's planktic organisms were eliminated, an associated reduction in productivity led to a partial transfer of dissolved carbon dioxide from the oceans to the atmosphere. This resulted in a large increase of the atmospheric carbon dioxide during the next 50,000 years, which is believed to have caused a temperature rise revealed by the oxygen-isotope data. The lowermost Tertiary sediments at site 524 include fossils with Cretaceous affinities, which may include both reworked individuals and some forms that survived for a while after the catastrophe. Our data indicate that many of the Cretaceous pelagic organisms became extinct over a period of a few tens of thousands of years, and do not contradict the scenario of cometary impact as a cause of mass mortality in the oceans, as suggested by an iridium anomaly at the Cretaceous-Tertiary boundary.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Mass Mortality and its Environmental and Evolutionary Consequences does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Mass Mortality and its Environmental and Evolutionary Consequences, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mass Mortality and its Environmental and Evolutionary Consequences will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-843905

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.