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Book Chapters

Browse more than 5,500 book chapters authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.

Filter Total Items: 6155

Collision of astronomically observable bodies with the Earth Collision of astronomically observable bodies with the Earth

There are at present about 1,000 Earth-crossing bodies of asteroidal appearance that have diameters greater than 1 km. It is calculated that on the average about 3 of these bodies impact the Earth every million years. Because there are many more small bodies than large ones, impacts of 10-km-diameter objects, as postulated by Alvarez and others to explain the Cretaceous/Tertiary...
Authors
G. W. Wetherill, Eugene Merle Shoemaker

The geology of Europa The geology of Europa

The map units and lineations of Europa are detailed, and the geologic processes, and history, and thick and thin ice models of the satellite are discussed. It is concluded that Europa lacks evidence of a horizontally stratified crust; the geology appears characterized by disruption of the crust and intrusions into an icy shell. The surface consists of plains and mottled terrain, the...
Authors
Baerbel K. Lucchitta, Laurence A. Soderblom

A case history of a dynamic resource--the red fox A case history of a dynamic resource--the red fox

Red fox (Vulpes vulpes) population trends in midwestern North America since 1800 were examined. During 1801-1900, the red fox expanded its range south to include most of the region, but populations remained low in most areas. During 1901-30, it became scarce or absent in many northern areas but was common in southern areas. During 1931-45, populations in most of the region increased to...
Authors
A.B. Sargeant
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