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Paleoceanographic events and deep-sea ostracodes
Science (New York, N.Y.)
|June 22, 1984
Summary
Paleoceanographic events significantly impacted deep-sea ostracodes. The Cretaceous-Tertiary boundary and psychrosphere formation events dramatically reshaped marine ecosystems and ostracode distribution.
Area of Science:
- Paleoceanography
- Marine Biology
- Paleontology
Background:
- The deep sea harbors unique fauna adapted to extreme conditions.
- Ostracodes are valuable microfossils for reconstructing past ocean environments.
- Understanding paleoceanographic events is crucial for marine ecosystem studies.
Purpose of the Study:
- To investigate the impact of major paleoceanographic events on deep-sea benthic ostracode faunas.
- To correlate changes in ostracode distribution with specific geological time intervals and oceanographic shifts.
Main Methods:
- Analysis of global deep-sea benthic ostracode faunal changes.
- Correlation of faunal shifts with eight recognized or theorized paleoceanographic events over the past 70 million years.
Main Results:
- Two events, the Cretaceous-Tertiary boundary event (66 Ma) and the psychrosphere formation (40 Ma), showed the most significant impacts.
- Prior to 40 Ma, ostracodes were provincial despite free radiation into deeper waters.
- Thermal stratification led to the isolation and adaptation of deep-water taxa, survivors of the K-T event.
Conclusions:
- The Cretaceous-Tertiary boundary and psychrosphere formation events were pivotal in shaping deep-sea ostracode diversity and biogeography.
- Oceanographic changes, particularly thermal stratification, created new, widespread, and frigid ecosystems for surviving ostracode lineages.
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