Development
This climatic and chronological framework was composed of four glacial and interglacial stages. It was developed between 1894 and 1909 by geomorphologists and Quaternary geologists to subdivide glacial and nonglacial deposits within the United States of America. 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. 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".
Read more about this topic: Yarmouthian (stage)
Famous quotes containing the word development:
“Other nations have tried to check ... the fulfillment of our manifest destiny to overspread the continent allotted by Providence for the free development of our yearly multiplying millions.”
—John Louis O’Sullivan (1813–1895)
“Such condition of suspended judgment indeed, in its more genial development and under felicitous culture, is but the expectation, the receptivity, of the faithful scholar, determined not to foreclose what is still a question—the “philosophic temper,” in short, for which a survival of query will be still the salt of truth, even in the most absolutely ascertained knowledge.”
—Walter Pater (1839–1894)
“The man, or the boy, in his development is psychologically deterred from incorporating serving characteristics by an easily observable fact: there are already people around who are clearly meant to serve and they are girls and women. To perform the activities these people are doing is to risk being, and being thought of, and thinking of oneself, as a woman. This has been made a terrifying prospect and has been made to constitute a major threat to masculine identity.”
—Jean Baker Miller (20th century)