Researchers studying prehistoric rocks and fossils from Mount Ashibetsu in Japan have refined the timing and duration of Ocean Anoxic Event 1a (OAE 1a), a major environmental disruption that depleted oxygen in Earth’s oceans and triggered significant extinctions, particularly among plankton.
Key Findings:
- Timing and Duration:
- OAE 1a began approximately 119.5 million years ago during the Mesozoic Era.
- The event lasted for just over 1.1 million years.
- Cause of the Anoxic Event:
- Researchers have strengthened the hypothesis that massive undersea volcanic eruptions released large amounts of carbon dioxide (CO2), leading to:
- Global warming.
- Oxygen depletion (anoxia) in the oceans.
- The study provides precise evidence linking volcanic CO2 emissions to this catastrophic environmental event.
- Researchers have strengthened the hypothesis that massive undersea volcanic eruptions released large amounts of carbon dioxide (CO2), leading to:
- Research Methodology:
- By analyzing rock layers and fossil evidence from Mount Ashibetsu, the team pinpointed the eruption’s timing and its correlation with OAE 1a.
Significance of the Findings:
- Understanding Climate Responses: The study sheds light on how Earth’s climate and ocean systems responded to extreme environmental stress caused by rapid CO2 increases.
- Modern Implications: Insights from this prehistoric event offer parallels to current anthropogenic climate change, where rising CO2 levels are also causing global warming and ocean stress. Understanding OAE 1a provides a historical framework for assessing the long-term impacts of carbon emissions on marine ecosystems and global climates.
(Source: PHYS)
