Publications

The paleoclimatic history of western Utah is being investigated as part of the USGS Global Change and Climate History Program studies of long-term climatic changes in the western United States. The initial objective of the study is to document the environmental conditions during the mid-Pliocene period of warmer-than-modern global climates (the focus of the USGS Pliocene Research, Interpretation,

Dust samples collected annually for 5 years from 55 sites in southern Nevada and California provide the first regional source of information on modern rates of dust deposition, grain size, and mineralogical and chemical composition relative to climate and to type and lithology of dust source. The average silt and clay flux (rate of deposition) in southern Nevada and southeastern California ranges

Stable oxygen and carbon isotope geochemistry of ostracode valves, abundance and assemblages of ostracode species, and sedimentological parameters from cores taken in Williams and Shingobee Lakes in north-central Minnesota show changes in climatic and hydrologic history during the Holocene. Isotopic records are consistent with the following scenario:Before 9800 yr B.P. the two lakes were connected

During the Pinedale (Late Wisconsinan) glaciation, an outlet glacier from a mountain ice field flowed eastward across the Continental Divide through Marias Pass in northwestern Montana. This outlet glacier was the major source of the Two Medicine glacier, a large piedmont glacier that extended from the mountain front east about 55 km onto the plains. An accelerator mass spectrometry radiocarbon ag

Estimates of the epicentral location and maximum intensity of the earthquake of 14 December 1872, the largest and oldest historic earthquake documented in the Pacific Northwest, are controversial largely because the estimates are based on ground effects. The Ribbon Cliff landslide is one of the more critical ground effects used to argue that the epicenter was in the vicinity of Lake Chelan in cent

Eolian sediment covers about 60% of Colorado east of the Rocky Mountains; about 30% of the sediment is sand and 70% is loess. Initially, flood plains were the principal sources of eolian sediment, but during the Holocene, dunes formed from older eolian sand and alluvium on uplands. Since latest Pleistocene time, dominant dune-forming winds have been northwesterly in the northern part of the region

No abstract available.

No abstract available.

The isotopic composition of strontium contained in the carbonate fractions of soils provides an excellent tracer which can be used to test models for their origin. This paper reports data on surface coatings and cements, eolian sediments, playas and alluvial fan soils which help to constrain a model for formation of the extensive calcretes and fault infillings in the Yucca Mountain region. The pla

The accumulation of radon indoors is commonly due to movement of radon from adjacent soil and rock into a building foundation through joints, utility openings, cracks, or porous block walls. When air pressure inside the building is lower than that in the soil, pressure-driven flow of radonbearing soil gas can occur (see Chapter 2). Whether or not an indoor radon problem results depends on: (1) the

No abstract available.

Sedimentologic and geochemical studies of box and gravity cores recovered from the Black Sea during the first leg of a multileg international Black Sea expedition in 1988 allow reconstruction of the basinwide Holocene environmental history of the Black Sea. In the deeper parts of the basin, box cores typically recovered a flocculent surface layer (“fluff”), laminated coccolith marls of Unit I (25–