Skip to main content
U.S. flag

An official website of the United States government

Publications

Filter Total Items: 1441

Isotopic studies of fracture coatings at Yucca Mountain, Nevada, USA Isotopic studies of fracture coatings at Yucca Mountain, Nevada, USA

No abstract available.
Authors
Brian D. Marshall, J. F. Whelan, Zell E. Peterman, Kiyoto Futa, Shannon A. Mahan, John S. Stuckless

Role of chemical change in the paleomagnetic record Role of chemical change in the paleomagnetic record

To produce an outline of how either to isolate or capitalize on changes in magnetic properties resulting from chemical changes, the workshop, “Effects of Chemical Changes on Magnetization,” was held in Santa Fe, N. Mex. from August 13 to 16. It was sponsored by the Institute for Rock Magnetism (IRM) in Minneapolis, Minn., and funded by the National Science Foundation. Graduate students...
Authors
S. Banerjee, Richard L. Reynolds

Isotopic signatures of black tektites from the K‐T boundary on Haiti: Implications for the age and type of source material Isotopic signatures of black tektites from the K‐T boundary on Haiti: Implications for the age and type of source material

U‐Th‐Pb, Rb‐Sr, and Sm‐Nd isotopic signatures of corroded, but unaltered, black glassy tektites from Cretaceous‐Tertiary (K‐T) boundary rock on Haiti are not consistent with their derivation from an impact on MOR‐derived oceanic crust or continental regions involving middle Proterozoic or older crustal material. Two single‐grain and two batches of these tektites yielded present‐day ∍Nd =...
Authors
Wayne R. Premo, G. A. Izett

Allochthonous impact-shocked rocks and superimposed deformations at the Beaverhead site in southwest Montana Allochthonous impact-shocked rocks and superimposed deformations at the Beaverhead site in southwest Montana

Upward-pointing shatter cones in sandstones of uncertain age (Middle Proterozoic? to Lower Cambrian?) and older crystalline basement rocks are exposed over an area of approximately 25 × 8 km in southwestern Montana. These shatter cones, together with pseudotachylites and breccias of various types (particularly in basement gneisses), are inferred to be products of a meteorite or cometary...
Authors
R.B. Hargraves, Karl S. Kellogg, P.S. Fiske, S.B. Hougen

Effects of weather and soil characteristics on temporal variations in soil-gas radon concentrations Effects of weather and soil characteristics on temporal variations in soil-gas radon concentrations

Concentrations of radon-222 in soil gas measured over about 1 yr at a monitoring site in Denver, Colorado, vary by as much as an order of magnitude seasonally and as much as severalfold in response to changes in weather. The primary weather factors that influence soil-gas radon concentrations are precipitation and barometric pressure. Soil characteristics are important in determining the...
Authors
R. Randall Schumann, Douglass E. Owen, Sigrid Asher-Bolinder

Chapter 4: Cretaceous thrusting and Neogene block rotation in the northern Portneuf Range region, southeastern Idaho Chapter 4: Cretaceous thrusting and Neogene block rotation in the northern Portneuf Range region, southeastern Idaho

The Putnam thrust has long been recognized as an important Mesozoic structure in the northern Portneuf Range, southeastern Idaho. At most localities, the thrust places Ordovician rocks above Permian and Pennsylvanian rocks, although near its southeastern extent, it ramps laterally downsection to the southeast. At its southeasternmost exposures, Cambrian rocks are juxtaposed above...
Authors
Karl S. Kellogg

The extent of temporal smearing in surface-temperature histories derived from borehole temperature measurements The extent of temporal smearing in surface-temperature histories derived from borehole temperature measurements

The ability of borehole temperature data to resolve past climatic events is investigated using Backus-Gilbert inversion methods. Two experimental approaches are considered: (1) the data consist of a single borehole temperature profile, and (2) the data consist of climatically-induced temperature transients measured within a borehole during a monitoring experiment. The sensitivity of the...
Authors
Gary D. Clow
Was this page helpful?