Since the Yarmouthian (Yarmouth) interglacial was named, the stratigraphy of Pleistocene deposits was found to be far more complex than the two glacial tills and one volcanic ash bed on which the Yarmouthian, Kansan, Nebraskan, and Aftonian glacial - interglacial nomenclature was originally based.
Detailed research by various geomorphologists and Quaternary geologists demonstrated that the two glacial tills and one ash bed stratigraphic model, on which the Yarmouthian, Kansan, Nebraskan, and Aftonian glacial - interglacial nomenclature was based, was completely wrong.
Later the Yarmouth (Yarmouthian) stage in Illinois was defined on the basis of the Yarmouth Paleosol (Soil) developed in the surface of what were thought at that time to be "Kansan" glacial tills and buried by Illionian glacial tills of the Glasford Formation in southeast Iowa and east-central Illinois.
At this time, it was incorrectly presumed that the Yarmouth Paleosol formed during a single interglacial stage that separated a younger glacial stage, the Illinoian Glaciation, represented by the sediments of the Glasford Formation in Illinois and the glacial deposits of an older glacial stage, called the "Kansan Glaciation".
When considering the best places to have a dip in the waters, you may first think of the Bahamas or the Mediterranean.
This new series is a golden opportunity to have a secret peek into the lives of the reception-age children as they take their first steps towards independence, forge friendships and find their feet away from their families.For example, the so-called "Kansan" glacial sediments in which the Yarmouth Soil developed are now known to date to different periods of glaciation depending on where it is examined within the Midwest and other parts of North America.In addition, fission track dating and geochemical analysis demonstrated what was thought to be one volcanic ash layer was actually three separate volcanic ash layers, i.e.From youngest to oldest, they were the Wisconsin glaciation, Sangamonian (interglacial), Illinoian Stage (glacial), Yarmouthian, Kansan glaciation, Aftonian (interglacial), and Nebraskan stages.
The Yarmouthian (Yarmouth) Interglacial was defined first on the basis of "interglacial" sediments encountered in wells dug in southeasterm Iowa.
the 602,000 year-old Lava Creek B volcanic ash; the 1,293,000 year-old Mesa Falls volcanic ash, and the 2,003,000 year-old Huckleberry volcanic ash.