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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: 6158

Yellowstone bears Yellowstone bears

No abstract available.
Authors
R.R. Knight, B.M. Blanchard, P. Schullery

Potassium-calcium decay system Potassium-calcium decay system

Potassium has three isotopes (see Potassium); potassium-40 ( 40K) is radioactive and decays to both calcium-40 ( 40Ca) and argon-40 ( 40Ar). The combined half-life of 40K is 1.25 billion years. The branched decay scheme of 40K is shown in Figure P33. It decays by β- decay to 40Ca and to 40Ar by both electron capture and positron decay (see Potassium-argon decay system). Although 89.52%...
Authors
Brian D. Marshall

Dating methods Dating methods

One of the greatest contributions of geochemistry to man's knowledge of the Earth and solar system has been the development and application of chemical and isotopic techniques used to measure the passage of time. Rates of geologic processes, rates of biological evolution, and contemporaneity of past events all depend on accurate ages of geologic materials. Many geochemical methods have...
Authors
Brian D. Marshall

Continental diatoms as indicators of long-term environmental change Continental diatoms as indicators of long-term environmental change

It is curious that diatoms, whose short lifespans and capacity for rapid regeneration make them especially suitable for short-term paleoenvironmental studies, would also have a significant role as indicators of long-term environmental change. This chapter explores the nature of long diatom records, their relation to global environmental changes, guidelines for their interpretation, and...
Authors
J. Platt Bradbury

Laramide to Holocene structural development of the northern Colorado Front Range Laramide to Holocene structural development of the northern Colorado Front Range

The Rocky Mountain province of the United States is a classic basement-involved foreland orogen. Deformation during the Late Cretaceous to Eocene Laramide orogeny created an anastomosing system of basement-cored arches that bound the northern and eastern margins of the Colorado Plateau and the elliptical sedimentary basins of the Rockies. The tectonic mechanism for Laramide deformation...
Authors
Eric A. Erslev, Karl S. Kellogg, Bruce Bryant, Timothy K. Ehrlich, Steven M. Holdaway, Charles W. Naeser

PB isotopes, ore deposits, and metallogenic terranes PB isotopes, ore deposits, and metallogenic terranes

No abstract available.
Authors
R. M. Tosdal, J. L. Wooden, R. M. Bouse

Hydrogeologic structure of the Newark Basin, Pennsylvania, from borehole geophysical logs Hydrogeologic structure of the Newark Basin, Pennsylvania, from borehole geophysical logs

The Brunswick and the underlying Lockatong Formations are comprised of littrifled Mesozoic sediments that constitute part of the Newark Basin in southeastern Pennsylvania (USA). These fractured rocks form an important regional aquifer that consists of gmdational sequences of shale, siltstone, and sandstone, with fluid transport occurring primarily in fractures. An extensive suite of...
Authors
R. H. Morin, L.A. Senior, E.R. Decker

Common Raven Common Raven

No abstract available.
Authors
W.I. Boarman, B. Heinrich
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