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Accueil du site → Doctorat → États-Unis → 1984 → Chronologic and climatic control on soil development, northern Bighorn Basin, Wyoming and Montana

Colorado University Boulder (1984)

Chronologic and climatic control on soil development, northern Bighorn Basin, Wyoming and Montana

Reheis, M. C.

Titre : Chronologic and climatic control on soil development, northern Bighorn Basin, Wyoming and Montana

Auteur : Reheis, M. C.

Université de soutenance : Colorado University Boulder

Grade : Doctor of Philosophy (PhD) 1984

Résumé
Four soil chronosequences in the northern Bighorn Basin develop at different rates in different climates. Soils along Rock Creek are formed in granitic glaciofluvial terrace deposits. Multivariate statistics show that properties develop at power or logarimthmic rates in mountain-front soils (cool moist climate), whereas properties of basin soils (semiarid climate) develop at logarithmic or linear rates. The Kane fan soils (arid climate) are formed in calcareous alluvial deposits of Cottonwood Creek and develop at linear rates. Linear age trends of A-horizon properties in semiarid and arid climates reflect the cumulative addition of aerosolic dust, whereas log or power trends in basin B horizons and in all mountain-front horizons are attributed to decreasing rates of chemical weathering with time. The strongest climatic differences among the chronosequences are : (1) log or power rates of soil development in moist areas, as opposed to linear rates in dry areas ; (2) CaCO3 and gypsum accumulation in semiarid and arid soils respectively ; and (3) clay mineralogy.

Mots clés : BIGHORN MOUNTAINS (MT-WY), CHRONOLOGY, CLIMATE, MONTANA, SOILS, WYOMING, ARID LANDS, GYPSUM, MOISTURE, STATISTICAL ANALYSIS, WEATHERING

Présentation (SAO-NASA)

Page publiée le 11 novembre 2013, mise à jour le 17 novembre 2018