Filters: Tags: Black Mesa (X)
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Eolian deposition on the semiarid southern Colorado Plateau has been attributed to episodic aridity during the Quaternary Period. However, OSL ages from three topographically controlled (e.g. falling) dunes on Black Mesa in northeastern Arizona indicate that eolian sediments there were deposited in deep tributary valleys as early as 35–30 ka, with most sand deposited before 20 ka. In contrast, the oldest OSL ages for sand sheets fall within the Pleistocene-Holocene climatic transition (~ 12–8 ka). Thus most eolian sediment accumulated on Black Mesa under climatic conditions that were in general cooler, moister, and more variable than today, not more arid, pointing to a considerable increase in sediment supply....
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Black Mesa,
Eolian geomorphology,
Falling dunes,
Linear dunes,
OSL geochronology,
This is a point coverage containing 12 years (1984 through 1995) of coal mining history in the Colorado Plateau coal assessment study area. This layer was derived from the Mine Safety and Health Administration's (MSHA) Information Resource Center data for the years 1984 through 1995.
Categories: Data,
pre-SM502.8;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Arizona,
Black Mesa,
Colorado,
Colorado Plateau,
Greater Green River Basin,
USGS Historical Quadrangle in GeoPDF.
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