Publications

The Nenana coal basin extends 240 km in length and 1.5-50 krn in width along the northern foothills of the Alaska Range in central Alaska. Located at the western end of the Nenana basin is the Usibelli Coal Mine, approximately 120 km southwest of Fairbanks. The Tertiary Usibelli Group consists of coal-bearing fluvial and lacustrine sedimentary deposits that were derived from the Yukon...

The production, consumption, and applications of fluorspar are reviewed. In 1994, the U.S. exported about 45 kt of fluorspar, but, according to the U.S. Bureau of the Census, 493 kt were imported during the same period. Consumption, according to preliminary figures from the U.S. Bureau of Mines, was about 473 kt. China continued to be the main supplier of imports to the U.S. with 61...

The Clipper Mountains in the eastern Mojave Desert expose evidence of Jurassic plutonic intrusion along what was an active thrust at the east fringe of the exposed Cordilleran Jurassic magmatic arc. This event occurred during a period of widespread arc magmatism and intra-arc thrusting in the Cordillera related to subduction under the west edge of North America. Jurassic plutons in the...

This Open-File report is a digital geologic map database. This pamphlet serves to introduce and describe the digital data. There is no paper map included in the Open-File report. This digital map database is compiled from previously published sources combined with some new mapping and modifications in nomenclature. The geologic map database delineates map units that are identified by...

Over 62 percent of the 193,000 metric tons of gold discovered to date is located in four countries and more than 68 percent occurs in four types of mineral deposits. About 55 percent of the 1,740,000 metric tons of silver found is in four countries and 45 percent is in four types of deposits. Fifty-six percent of the 1.52 billion metric tons of discovered copper is from four countries...

No abstract available.

When a powerful earthquake strikes an urban region, damage concentrates not only near the quake's source. Damage can also occur many miles from the source in areas of soft ground. In recent years, scientists have developed ways to identify and map these areas of high seismic hazard. This advance has spurred pioneering legislation to reduce earthquake losses in areas of greatest hazard.

Crystalline basement in central California extends westward from the exposed Sierra Nevada beneath the sedimentary fill of the Great Valley and under the eastern edge of the Coast Ranges at mid-crustal depth. The surface of this basement is defined from three types of control: in the Sierra Nevada from the topography itself, beneath the eastern two thirds of the Great Valley in...

Part of the 1994 Industrial Minerals Review. The production, consumption, and applications of strontium are reviewed. Consumption for the year is estimated to have been about 35 kt for strontium contained in celestite, strontium carbonate, and strontium nitrate. Exports of strontium totaled only about 1.1 kt for the year. U.S. strontium imports and consumption increased about 30 percent...

Part of the 1994 Industrial Minerals Review. The production, consumption, and applications of construction aggregates are reviewed. In 1994, the production of construction aggregates, which includes crushed stone and construction sand and gravel combined, increased 7.7 percent to 2.14 Gt compared with the previous year. These record production levels are mostly a result of funding for...

Every year in the United States, millions of measurements are made on the chemical composition of items that affect us on a daily basis. Determining the accuracy of these measurements is based on the analysis of appropriate reference materials whose composition was previously determined through rigorous testing. Today, reference materials help us evaluate the composition of the food we

This Open-File report is a digital geologic map database. A pamphlet serves to introduce and describe the digital data. There is no paper map included in the Open-File report. This digital map database is compiled from previously published sources combined with some new mapping and modifications in nomenclature. The geologic map database delineates map units that are identified by...