Images

A view east from Munra Point, Oregon showing Bonneville Dam, the Bonneville landslide, and snowy Mount Adams in the hazy distance.

Controlled laboratory experiments are conducted to characterize the biogeochemical processes controlling uranium bioavailability

Research Geologist Geoff Phelps measuring basalt flow thickness and magnetic susceptibility of individual basalt flows of the Broadwell Mesa Basalt in the central Mojave Desert near Ludlow, CA. 

Research Geologist Kevin Schmidt and Geoff Phelps examine satellite imagery on tablet computers during geologic mapping field work near Broadwell Mesa while supported by mule pack train.  

USGS scientist, Mark Reid, in front of the exact place where the main body of the landslide, composed of glacial lacustrine clay, overrode the liquified alluvium of the river valley.

The lower Colorado River supports a verdant delta at the upper end of Lake Havasu, a reservoir on the Arizona-California border. Lake Havasu filled in 1938 following the completion of Parker Dam.

Acidic waters from Cement Creek are discharged in the circum-neutral Animas River near Keystone, Colorado. Mixing of the waters produces colloidal-size iron and aluminum hydroxide precipitates.

Linear tracts and small patches of well rounded and varnished pebbles and cobbles mark the traces of ancient channels, bars, and floodplain terraces of the lower Colorado River.

Deformed sediment of the Bouse Formation in Chemehuevi Valley, California. Complex deformation is a likely consequence of subaqueous mass wasting of part of a growing delta of the Colorado River.

Outcrop of the Bouse Formation in Chemehuevi Valley, Whipple Mountains, Calfornia in background. The Bouse Formation includes sedimentary deposits that chronicle the first arrival of Colorado River water into desert basins downstream from Grand Canyon. The deposits in Chemehuevi Valley are particularly well-exposed.

USGS geologic mappers walkinbg out an intermediate age (likely middle Pleistocene) alluvial fan surface near Broadwell Mesa, in the northern Bristol Mountains, Kelso Dunes Wilderness Area, Mojave Desert, California.

A view west of the western Columbia River Gorge National Scenic Area from near Cascade Locks, Oregon. The toe of the Bonneville landslide is on the right, which blocked the Columbia River about 500 years ago.

Summer flash-floods can introduce large amounts, of fine reddish-orange sediment to the Colorado River with spectacular results

Freshwater tidal marsh of the Columbia River estuary, Cathlamet Bay in foreground, uplifted coastal ranges of the Cascadia forearc of Washington in background.

Union for International Cancer Control (UICC) Asbestos Anthophyllite Standard.

Union for International Cancer Control (UICC) asbestos chrysotile 'B' standard.

Union for International Cancer Control (UICC) asbestos chrysotile 'A' standard.

Union for International Cancer Control (UICC) asbestos crocidolite standard.

Cascadia encompasses the volcanoes of the Cascade Range and the subduction zone that feeds them. The region is home to nearly 10 million people. Where and how these people live, work, and play are influenced by the shape, or physiography, of Cascadia. This map is a tool for visualizing and interpreting the physiography of Cascadia.

Physiographic image of the Pacific Northwest, modified from USGS I-2689 by Haugerud (2004) Physiographic-Cascadia

Oblique orbital view of California looking NNW from above NW Sonora, Mexico, and northern Gulf of California