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This dataset includes tables of stratigraphic age-depth information for Paisley Caves 2 and 5, in Oregon U.S.A., along with tables of fish bone abundance and stable and strontium isotopic data for fish remains and geological samples from the study area surrounding the Paisley Caves.
This dataset is the assembled analytical results of geochemical, petrographic, and geochronologic data for samples, principally those of unmineralized Tertiary volcanic rocks, from the Tonopah, Divide, and Goldfield mining districts of west-central Nevada. Much of the data presented here for the Tonopah and Divide districts are for samples collected by Bonham and Garside (1979) during geologic mapping in and around those districts, whereas much of that for samples from the Goldfield district were obtained by Ashley (1974; 1979; 1990). Additional data were derived from samples collected between 2012–2017, as part of the U.S. Geological Survey Mineral Resources Program funded project titled: “Magmatic-tectonic history...
Categories: Data;
Tags: Ar,
Divide mining district,
Economic Geology,
Esmeralda County,
Fraction Tuff,
This dataset accompanies publication 'Multiproxy Cretaceous-Paleogene boundary event stratigraphy: an Umbria-Marche basin-wide perspective'.
Categories: Data;
Tags: 40Ar/39Ar,
Argon Geochronology Laboratory,
GGGSC,
Geochemistry,
Geology, Geophysics, and Geochemistry Science Center,
This dataset accompanies publication 'A supervolcano and its sidekicks: A 100 ka eruptive chronology of the Fish Canyon Tuff and associated units of the La Garita magmatic system', in review in Geology, which analyzed eruptive products from the La Garita caldera.
Sediment cores were collected in Great Dismal Swamp National Wildlife Refuge in November, 2017 to advance understanding of climate- and land-management driven changes in vegetation, hydrology, and fire regimes. Radiocarbon dates were obtained from samples in two cores (GDS-519-3-21-2017 and GDS-520-3-21-2017) to generate age models for the cores. Bulk sediment samples, charcoal, plant macrofossils, and pollen residue were selected at the USGS in Reston, Virginia and submitted to Beta Analytic, Inc. and the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) laboratories for radiocarbon dating. Those laboratories provided both radiocarbon ages and stable carbon isotope (delta 13C) results, which can be...
Despite its subdued expression and isolated location within the Great Plains of southeastern Colorado, the 80-km-long Cheraw fault may be one of the most active faults in North America east of the Southern Rocky Mountains. We present geomorphic analyses, geochronology, and paleoseismic trenching data to 1) document the rupture history of the ~45-km-long southwestern section of the Cheraw fault over the past ~19 ka, and 2) evaluate slip-rate changes for the entire fault over the past ~200 ka. Results from new trenches excavated at the Old Ranch site show evidence of four surface-rupture events since ~19 ka, each with an average vertical displacement of 0.75 m. An additional event is likely only slightly older than...
Categories: Data;
Tags: Arkansas River,
Basin and Range,
Cheraw Fault,
Eastern Colorado,
Geomorphology,
This dataset accompanies publication: Minor, S.A., Caine, J.S., Ruleman, C.A., Fridrich, C.J., Chan, C.F., Brandt, T.R., Morgan,L.E., Cosca, M.A., and Grauch, V.J.S., in prep, Geologic map of the Poncha Pass area, Chaffee, Fremont, and Saguache Counties, Colorado: U.S. Geological Survey Scientific Investigations Map (in revision), 2 plates, 27 ms. p, 1:24,000 scale.
This dataset accompanies publication 'Characteristics and 40Ar/39Ar geochronology of the Erdenet Cu-Mo deposit, Mongolia', Imants Kavalieris, Bat-Erdene Khashgerel, Leah E. Morgan, Alexander Undrakhtamir, Adiya Borohul. Economic Geology Aug 2017, 112 (5) 1033-1053; DOI: 10.5382/econgeo.2017.4500
This report summarizes the geochronologic results from boulders deposited on glacial moraines in the southern Sawatch and Sangre de Cristo Mountains of south-central Colorado. Within this report are detailed the methodology used to collect samples of whole rock, determine the concentrations of cosmogenic beryllium 10 in purified quartz isolated from those samples, and use those nuclide concentrations to calculate surface exposure ages. This report should be used as supplementary material for any publication(s) that uses the nuclide concentrations and/or ages reported herein. This version supersedes all previous age estimates and reports.
This data release includes laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) U-Pb zircon geochronology data to determine the ages of Challis igneous rocks in the Thunder Mountain volcanic field and dikes west of the volcanic field, especially in and near the Stibnite-Yellow Pine mining district, ID. These efforts were made to help understand the stratigraphy and lithologic characteristics of the Challis igneous rocks by determining their absolute ages.
Categories: Data;
Tags: Challis,
GGGSC,
Geochronology,
Geology, Geophysics, and Geochemistry Science Center,
Idaho,
This dataset accompanies planned publication 'Near-Ridge Magmatism Constrained Using 40Ar/39Ar Dating of Enriched MORB from the 8°20' N Seamount Chain'. The Ar/Ar data are for samples that record the volcanic history of the area. The geochronology provides time constraints for the eruption of rocks studied in the manuscript. Samples were collected from the 8°20' N seamount chain by Molly Anderson (University of Florida), who sent them to the USGS Denver Argon Geochronology Laboratory for Ar/Ar analysis.
Categories: Data;
Tags: "Marine Geology"],
"Volcanology",
East Pacific Rise,
GGGSC,
Geology, Geophysics, and Geochemistry Science Center,
This data release includes whole rock geochemical data, and uranium-lead isotopic data collected by both Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) and Sensitive High Resolution Ion Microprobe-Reverse Geometry (SHRIMP-RG) methods. Whole rock geochemistry was collected by Activation Laboratories in Ancaster, Ontario. LA-ICP-MS data was collected at the PLASMA at the USGS in Denver, Colorado. SHRIMP-RG data was collected at the USGS-Stanford SHRIMP-RG in Palo Alto, California. Rock samples for all methods were collected by Mark Carter of the USGS. The whole rock geochemistry and uranium lead isotopic data constrain the age and origin of rocks in the newly defined Dinwiddie Terrane of eastern...
Categories: Data;
Tags: FBGC,
Florence Bascom Geoscience Center,
Geochemistry,
Geochemistry,
Geochronology,
Samples of vein-type magmatic-steam alunite were collected over several field seasons from five mines and prospects (L&N, Mt. Edna, Christmas, upper Mineral Products, and Close In) in the Alunite Ridge and Deer Trail Mountain area, Marysvale, Utah, as well as a sample from the Deer Trail mine workings from which sericite was separated. The magmatic-steam alunite and sericite were analyzed by the 40Ar/39Ar method to constrain the timing and duration of magmatic activity associated with the intrusion of two porphyry stocks beneath Alunite Ridge and Deer Trail Mountain. In addition, a sample of a highly altered rhyolitic quartz porphyry dike was collected from the upper Mineral Products mine, from which zircons were...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: "Mineral Resources"],
40Ar/39Ar,
Alunite Ridge,
Deer Trail Mountain,
Denver Argon Geochronology Laboratory,
The Alaska Division of Geological & Geophysical Surveys (DGGS), in partnership with the U.S. National Cooperative Geologic Mapping Program, mapped approximately 450 mi2 of the Talkeetna Mountains region of central Alaska at 1:50,000 scale over the course of six weeks in 2014. This area contains significant exposures of Late Triassic mafic volcanics and gabbro sills that have been the focus of region-wide exploration for the Strategic and Critical platinum-group elements (PGEs). The area also exposes numerous inactive and possibly active faults which project through the area of proposed hydropower development. The resulting geologic map offers an improved understanding of the geology, structural history, and mineral...
This geologic map and report depicts portions of the Livengood B-3, B-4, C-3, and C-4 quadrangles. The Livengood area is a historically productive placer mining area approximately 80 road miles north of Fairbanks, Alaska. This report synthesizes recently collected and previously published agency and industry geologic data in a 1:50,000-scale comprehensive geologic map to build a better understanding of the geology and mineral-resource potential of the Livengood area. It expands and updates the Alaska Division of Geological & Geophysical Surveys (DGGS) Preliminary Interpretive Report (PIR) 2004-3 with the addition of new DGGS mapping and drillhole data from ITH, and integrates previously published DGGS surficial...
This 1:50,000 scale geologic map describes the distribution of unconsolidated deposits, identifies local geologic hazards, and provides information about the depositional environment and basic engineering properties of common surficial-geologic materials in and around Shaktoolik, Alaska. Map units are the result of combined field observations and aerial imagery interpretation. A suite of local ground observations were collected over a two-week period in July 2011 by a helicopter-supported team of DGGS geologists and collaborators. Field investigations included soil test pits, sample collection, soil and rock description, oblique aerial photography, and documentation of landscape morphology.
These 40Ar/39Ar thermochronologic data for biotite, hornblende, and K-feldspar from Butte granite country rock are for the study of the Butte mining district, U.S.A. Results of the study are described and interpreted in Lund and others (2018).
This dataset accompanies publication 'The influence of foreland structures on hinterland cooling: evaluating the drivers of exhumation in the eastern Bhutan Himalaya'. The Ar/Ar data provides time constraints for the cooling of rocks in the study area.
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: 40Ar/39Ar,
Argon Geochronology Laboratory,
Bhutan,
GGGSC,
Geochemistry,
Geologic mapping, characterization of geologic structures, and sampling for geochronology was completed in two areas of the northwestern Sangre de Cristo Mountains from 2011 through 2017. This data release provides the raw analytical data, metadata and sample information for 20 zircon U-Pb age analyses from laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS). The two areas include the Poncha Pass area where the entire 71/2’ Poncha Pass quadrangle and parts of five other quadrangles (Mount Ouray, Maysville, Salida West, Salida East, and Wellsville) were mapped at a scale of 1:24,000 (see Minor and others, 2019). The Deadman thrust fault is the second area, approximately 80 km southwest of the Poncha...
This dataset includes U-Pb detrital zircon age data for samples from the Ingleside and Lyons formations in north-central Colorado collected from Owl Canyon and Park Creek Reservoir, from the Molas and Hermosa formations in southwestern Colorado collected from Molas Pass, and from the Lykins formation and its equivalents along the Front Range and in southeastern Colorado. It accompanies publications 'The Permian-Triassic Transition in Colorado' published in Unfolding the Geology of the West: Geological Society of America Field Guide 44, and 'Detrital zircon geochronology of Pennsylvanian-Permian strata in Colorado: evidence for Appalachian-derived sediment and implications for the timing of Ancestral Rocky Mountains...
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