Coral dating uranium thorium
Atmospheric radiocarbon calibration beyond 11,900 cal BP from Lake Suigetsu.
Mass-spectrometric 230Th-234U-238U dating of the Devils Hole calcite vein.
Other factors that may have contributed to the formation and cessation of ice ages are the amount of greenhouse gases (mainly carbon dioxide, methane, and water vapor) in Earth’s atmosphere, the extent of sea and land-based ice across the northern hemisphere, and shifts in patterns of wind and ocean currents.
During ice ages, the most characteristic change to the planet has been the formation and spread large ice sheets and glaciers across much the Northern Hemisphere.
This will give us the precise measure of time that has elapsed since the disruption.
The basic principle of uranium – thorium series dating in corals is that uranium in oxygenated environments is about ten thousand times more soluble in seawater than thorium is.
The sheer weight of the ice at the height of the last ice age depressed Earth’s crust to such an extent that many areas are still slowly but noticeably rebounding to this day, 18,000 years after the retreat of the glaciers.[ MORE ]The formation of the ice also removed so much water from the global ocean that sea levels during ice ages were notably lower than interglacial periods such as the present day—as much as 400 feet lower during some periods.
The movement of the ice across the surface of the planet also scoured deep valleys, created extensive chains of hills known as moraines, and created extensive lakes, including the Great Lakes.
230Th/234U and 14C dating of a late Pleistocene stalagmite in Lobatse II cave, Botswana. Pleistocene extinction of Genyornis newtoni: human impact on Australian megafauna. Non-destructive gamma spectrometric U-series dating. Uranium series dating of impure carbonates: an isochron technic using total sample dissolution. A large drop in atmospheric 14C/12C and reduced melting in the Younger Dryas, documented with 230Th ages of corals.