Publications
Filter Total Items: 1441
Acoustic stratigraphy of Bear Lake, Utah-Idaho: late Quaternary sedimentation patterns in a simple half-graben Acoustic stratigraphy of Bear Lake, Utah-Idaho: late Quaternary sedimentation patterns in a simple half-graben
A 277-km network of high-resolution seismic-reflection profiles, supplemented with a sidescan-sonar mosaic of the lake floor, was collected in Bear Lake, Utah–Idaho, in order to explore the sedimentary framework of the lake's paleoclimate record. The acoustic stratigraphy is tied to a 120 m deep, continuously cored drill hole in the lake. Based on the age model for the drill core, the...
Authors
Steven M. Colman
Soil respiration in the cold desert environment of the Colorado Plateau (USA): Abiotic regulators and thresholds Soil respiration in the cold desert environment of the Colorado Plateau (USA): Abiotic regulators and thresholds
Decomposition is central to understanding ecosystem carbon exchange and nutrient-release processes. Unlike mesic ecosystems, which have been extensively studied, xeric landscapes have received little attention; as a result, abiotic soil-respiration regulatory processes are poorly understood in xeric environments. To provide a more complete and quantitative understanding about how abiotic...
Authors
D. P. Fernandez, J. C. Neff, Jayne Belnap, Richard L. Reynolds
Understanding the spatial heterogeneity of global environmental change in mountain regions Understanding the spatial heterogeneity of global environmental change in mountain regions
One of the challenges for global environmental change research is to understand how future climate changes will be expressed in mountain regions. The physiographic complexity of mountains creates environments that can be highly variable over relatively short distances. This spatial heterogeneity reflects a hierarchy of environmental controls. At regional scales, insolation and...
Authors
Sarah Shafer, Patrick J. Bartlein, Cathy Whitlock
Preliminary geologic map of southernmost Texas, United States, and parts of Tamaulipas and Nuevo Leon, Mexico: Environmental health investigations in the United States-Mexico border region Preliminary geologic map of southernmost Texas, United States, and parts of Tamaulipas and Nuevo Leon, Mexico: Environmental health investigations in the United States-Mexico border region
No abstract available.
Authors
William R. Page, D. Paco VanSistine, Kenzie J. Turner
Stratigraphy and structural history of the eastern edge of the Helena salient, Montana Stratigraphy and structural history of the eastern edge of the Helena salient, Montana
No abstract available.
Authors
Mitchell W. Reynolds
Structural termination of the Montana disturbed belt and its interaction with major structures of the continental autochthon Structural termination of the Montana disturbed belt and its interaction with major structures of the continental autochthon
No abstract available.
Authors
Mitchell W. Reynolds
Laccoliths of the southwest part of the Little Belt Mountains; their relation to ancestral structures of the Central Montana Uplift Laccoliths of the southwest part of the Little Belt Mountains; their relation to ancestral structures of the Central Montana Uplift
No abstract available.
Authors
Mitchell W. Reynolds
Radiocarbon dating of cores collected from Bear Lake, Utah and Idaho Radiocarbon dating of cores collected from Bear Lake, Utah and Idaho
No abstract available.
Authors
Steven M. Colman, Darrell S. Kaufman, Joseph G. Rosenbaum, John P. McGeehin
40Ar/39Ar and K-Ar geochronology and tectonic significance of the Upper Cretaceous Adel Mountain volcanics and spatially associated Tertiary igneous rocks, northwestern Montana 40Ar/39Ar and K-Ar geochronology and tectonic significance of the Upper Cretaceous Adel Mountain volcanics and spatially associated Tertiary igneous rocks, northwestern Montana
No abstract available.
Authors
Stephen S. Harlan, Lawrence W. Snee, Mitchell W. Reynolds, Harald H. Mehnert, R. G. Schmidt, Steve D. Sheriff, Anthony J. Irving
Contrasting Proterozoic basement complexes near the truncated margin of Laurentia, northwestern Sonora–Arizona international border region Contrasting Proterozoic basement complexes near the truncated margin of Laurentia, northwestern Sonora–Arizona international border region
We utilize new geological mapping, conventional isotope dilution–thermal ionization mass spectrometry (ID-TIMS) and sensitive high-resolution ion microprobe (SHRIMP) U-Pb zircon analyses, and whole-rock radiogenic isotope characteristics to distinguish two contrasting Proterozoic basement complexes in the international border region southeast of Yuma, Arizona. Strategically located near...
Authors
Jonathan A. Nourse, Wayne R. Premo, Alexander Iriondo, Eric R. Stahl
Evaluation of groundwater movement in the Frenchman Flat CAU using geochemical and isotopic analysis Evaluation of groundwater movement in the Frenchman Flat CAU using geochemical and isotopic analysis
The principal pathway for radionuclide migration from underground tests in Frenchman Flat, on the Nevada Test Site, to the accessible environment is groundwater flow. Two potential pathways for radionuclide transport via groundwater have been identified from hydrologic data: (1) radionuclide transport downward from the alluvial and volcanic aquifers into the underlying carbonate aquifer...
Authors
R. Hershey, J. Thomas, T. Rose, James B. Paces, I. M. Farnham, F. C. Benedict