Deep-sea sediment core
Part of Hall of Planet Earth.
Part of Hall of Planet Earth.
Walvis Ridge, southern Atlantic Ocean | circa 55–56 million years ago
The abrupt shift from light tan to dark sediment in the core modeled here shows a rapid increase in atmospheric CO2 during an event called the Paleocene-Eocene Thermal Maximum. Lighter layers, laid down before CO2 rose, contain shells from sea life. Darker layers mark when elevated CO2 raised ocean acidity, dissolving shells before they could reach the seafloor.
Courtesy of the International Ocean Discovery Program, JOIDES Resolution Science Operator