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Publications

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Three-dimensional geologic model of the southeastern Espanola Basin, Santa Fe County, New Mexico

This multimedia model and report show and describe digital three-dimensional faulted surfaces and volumes of lithologic units that confine and constrain the basin-fill aquifers within the Espanola Basin of north-central New Mexico. These aquifers are the primary groundwater resource for the cities of Santa Fe and Espanola, six Pueblo nations, and the surrounding areas. The model presented in this
Authors
Michael P. Pantea, Mark R. Hudson, V. J. S. Grauch, Scott A. Minor

Project plan-Surficial geologic mapping and hydrogeologic framework studies in the Greater Platte River Basins (Central Great Plains) in support of ecosystem and climate change research

The Greater Platte River Basin area spans a central part of the Midcontinent and Great Plains from the Rocky Mountains on the west to the Missouri River on the east, and is defined to include drainage areas of the Platte, Niobrara, and Republican Rivers, the Rainwater Basin, and other adjoining areas overlying the northern High Plains aquifer. The Greater Platte River Basin contains abundant surfi
Authors
Margaret E. Berry, Scott C. Lundstrom, Janet L. Slate, Daniel R. Muhs, David A. Sawyer, D. Paco VanSistine

DESI-Detection of early-season invasives (software-installation manual and user's guide version 1.0)

This report describes a software system for detecting early-season invasive plant species, such as cheatgrass. The report includes instructions for installing the software and serves as a user's guide in processing Landsat satellite remote sensing data to map the distributions of cheatgrass and other early-season invasive plants. The software was developed for application to the semi-arid regions
Authors
Raymond F. Kokaly

Detecting Cheatgrass on the Colorado Plateau using Landsat data: A tutorial for the DESI software

Invasive plant species disrupt native ecosystems and cause economic harm to public lands. In this report, an example of applying the Detection of Early Season Invasives software to mapping cheatgrass infestations is given. A discussion of each step of the DESI process is given, including selection of Landsat images. Tutorial data, covering a semi-arid area in southern Utah, are distributed with th
Authors
Raymond F. Kokaly

Geochemical characteristics of Holocene laminated sapropel (unit II) and underlying lacustrine unit III in the Black Sea

eg 1 of the 1988 R/V Knorr expeditions to the Black Sea recovered 90 gravity and box cores. The longest recovery by gravity cores was about 3 meters, with an average of about 2.5 meters, recovering all of the Holocene and upper Pleistocene sections in the Black Sea. During the latest Pleistocene glaciation, sea level dropped below the 35-meters-deep Bosporus outlet sill of the Black Sea. Therefore
Authors
Walter E. Dean, Michael A. Arthur

Volatile abundances and oxygen isotopes in basaltic to dacitic lavas on mid-ocean ridges: The role of assimilation at spreading centers

Most geochemical variability in MOR basalts is consistent with low- to moderate-pressure fractional crystallization of various mantle-derived parental melts. However, our geochemical data from MOR high-silica glasses, including new volatile and oxygen isotope data, suggest that assimilation of altered crustal material plays a significant role in the petrogenesis of dacites and may be important in
Authors
V.D. Wanless, M.R. Perfit, W.I. Ridley, P.J. Wallace, Craig B. Grimes, E.M. Klein

The geochemistry and petrogenesis of the Paleoproterozoic Green Mountain arc: A composite(?), bimodal, oceanic, fringing arc

The inferred subduction affinity of the ∼1780-Ma Green Mountain arc, a dominantly bimodal igneous terrane (together with immature marine and volcaniclastic sedimentary rocks) accreted to the southern margin of the Wyoming province, is integral to arc-accretion models of the Paleoproterozoic growth of southern Laurentia. Conversely, the dominantly bimodal nature of many putative arc-related igneous
Authors
D.S. Jones, C. G. Barnes, Wayne R. Premo, A.W. Snoke

Holocene record of precipitation seasonality from lake calcite δ18O in the central Rocky Mountains, United States

A context for recent hydroclimatic extremes and variability is provided by a ∼10 k.y. sediment carbonate oxygen isotope (δ18O) record at 5–100 yr resolution from Bison Lake, 3255 m above sea level, in northwestern Colorado (United States). Winter precipitation is the primary water source for the alpine headwater lake in the Upper Colorado River Basin and lake water δ18O measurements reflect season
Authors
Lesleigh Anderson

Sea-level history of the past two interglacial periods: New evidence from U-series dating of reef corals from south Florida

As a future warm-climate analog, much attention has been directed to studies of the Last Interglacial period or marine isotope substage (MIS) 5.5, which occurred ∼120,000 years ago. Nevertheless, there are still uncertainties with respect to its duration, warmth and magnitude of sea-level rise. Here we present new data from tectonically stable peninsular Florida and the Florida Keys that provide e
Authors
Daniel R. Muhs, Kathleen Simmons, R. Randall Schumann, R. B. Halley

Using luminescence dating of coarse matrix material to estimate the slip rate of the Astaneh fault, Iran

In this paper, we present optically and infrared stimulated luminescence (OSL and IRSL) ages for four samples from alluvial fan surfaces in the Astaneh Valley. This valley is located in the north-east part of the Alborz range in Iran. Our morphologic interpretations recognize at least three generations of fans in the study area, all of which have been displaced along the left-lateral strike-slip A
Authors
M. Rizza, Shannon A. Mahan, J.-F. Ritz, H. Nazari, J. Hollingsworth, R. Salamati

Recent surface temperature trends in the interior of East Antarctica from borehole firn temperature measurements and geophysical inverse methods

We use measured firn temperatures down to depths of 80 to 90 m at four locations in the interior of Dronning Maud Land, East Antarctica to derive surface temperature histories spanning the past few decades using two different inverse methods. We find that the mean surface temperatures near the ice divide (the highest‐elevation ridge of East Antarctic Ice Sheet) have increased approximately 1 to 1.
Authors
A. Muto, T. A. Scambos, K. Steffen, A.G. Slater, Gary D. Clow

Sea ice loss enhances wave action at the Arctic coast

Erosion rates of permafrost coasts along the Beaufort Sea accelerated over the past 50 years synchronously with Arctic‐wide declines in sea ice extent, suggesting a causal relationship between the two. A fetch‐limited wave model driven by sea ice position and local wind data from northern Alaska indicates that the exposure of permafrost bluffs to seawater increased by a factor of 2.5 during 1979–2
Authors
I. Overeem, R. Scott Anderson, C.W. Wobus, Gary D. Clow, Frank E. Urban, N. Matell