Glacial Chronology

North American glacial and interglacial stages of the Pleistocene are as follows: Pre-Nebraskan, Nebraskan glacial (began 1,800,000 years ago), Aftonian interglacial

(began 500,000 years ago), Kansan glacial (began 435,000 years ago), Yarmouth interglacial (began 300,000 years ago), Illinoian glacial (began 265,000 years ago), Sangamon interglacial (began 125,000 years ago), and Wisconsinian glacial (began 75,000 years ago). These stages correspond to the European stages of the Pre-Günz, Günz, Günz-Mindel, Mindel, Mindel-Riss, Riss, Riss-Würm, and Würm (Table 1). The Holocene (10,000 years ago to present) represents the postglacial age, from which we are likely to slip back into another glacial stage.

Detailed information on the chronology of the Pleistocene glaciation comes from oxygen isotope ratios in foraminifera skeletons preserved in deep-sea sediments. A fairly good record of oxygen isotope ratios for the last 160,000 years comes from glacial ice samples cored from the Greenland and Antarctic ice sheets since 1966.

Worm Farming

Worm Farming

Do You Want To Learn More About Green Living That Can Save You Money? Discover How To Create A Worm Farm From Scratch! Recycling has caught on with a more people as the years go by. Well, now theres another way to recycle that may seem unconventional at first, but it can save you money down the road.

Get My Free Ebook


Post a comment