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This data release contains luminescence and weather data from eastern Chuckwalla Valley, Riverside County, California. This study investigates sedimentary and geomorphic processes in eastern Chuckwalla Valley, Riverside County, California, a region of arid, basin-and-range terrain where extensive solar-energy development is planned. The objectives were to (1) measure local weather parameters and use them to model aeolian sediment transport potential; (2) identify surface sedimentary characteristics in representative localities; and (3) evaluate longer-term landscape evolution rates and processes by analyzing stratigraphy in combination with luminescence geochronology.
Burnsville Cove in Bath and Highland Counties (Virginia, USA) is a karst region in the Valley and Ridge Province of the Appalachian Mountains. The region contains many caves in Silurian to Devonian limestone, and is well suited for examining geologic controls on cave location and cave passage morphology. In Burnsville Cove, many caves are located preferentially near the axes of synclines and anticlines. For example, Butler Cave is an elongate cave where the trunk channel follows the axis of Sinking Creek syncline and most of the side passages follow joints at right angles to the syncline axis. In contrast, the Water Sinks Subway Cave, Owl Cave, and Helictite Cave have abundant maze patterns, and are located near...
Categories: Data,
Data Release - In Progress;
Tags: Bath County,
Burnsville Cove,
Butler Cave,
Geomorphology,
Highland County,
This data release contains luminescence data from the manuscript "Application of a luminescence-based sediment transport model" by Gray et al. It contains data from the luminescence measurements and experiments in the paper.
This data release contains luminescence, weather, and sediment grain-size data from eastern Chuckwalla Valley, Riverside County, California. This study investigates sedimentary and geomorphic processes in eastern Chuckwalla Valley, Riverside County, California, a region of arid, basin-and-range terrain where extensive solar-energy development is planned. The objectives were to (1) measure local weather parameters and use them to model aeolian sediment transport potential; (2) identify surface sedimentary characteristics in representative localities; and (3) evaluate longer-term landscape evolution rates and processes by analyzing stratigraphy in combination with luminescence geochronology. These data accompany East...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: California,
Chuckwalla Valley,
Geomorphology,
Riverside County,
USA,
This geologic map area of 5,430 km2 spans a reach of the lower Missouri River valley and adjoining uplands for about 100 kilometers east of Gavins Point Dam, the easternmost mainstem dam on the Missouri River. Understanding the surficial geologic history of the valley is relevant to natural resource management of the Missouri National Recreational River and is foundational to improved understanding of hydrology and ecology. This geodatabase is a synthesis of recent FEDMAP, EDMAP, and STATEMAP work of the National Cooperative Geologic Mapping Program with previously published maps of the geologic surveys of South Dakota, Nebraska, Iowa, and the USGS. Other data sources utilized for this map include NAIP ortho-imagery...
The Bureau of Reclamation's Scoggins Dam lies within the Gales Creek fault zone southwest of Hillsboro, Oregon. Recent geologic mapping shows the dam to overlie a potentially active strand of the fault. This report describes the geology of the dam in detail and confirms that the dam overlies a strand of the Gales Creek fault. The report documents small faults in the reservoir and off the north end of the dam along the Parsons Creek strand of the fault. The report further documents the geology of an alternative dam site downstream of the existing dam.
Stone rows, enclosures, structures and chambers can be found in the landscapes of Massachusetts and Rhode Island. Structures similar to those shown in the cover photo are documented elsewhere. The age, cultural affiliation, and purpose of these stone structures--which are found in a variety of forms, such as piles arranged in spatial configurations across landscapes, shapes suggesting animal effigies, platforms and chambers--have been the subject of much debate. Some have argued they are remnants of colonial agricultural and storage practices; others that they are prehistoric Native American ceremonial structures. Ascertaining the time periods of their creation had previously been impossible. We felt that optically...
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 release of digital geologic map data covers the Niobrara National Scenic River, a 76-mile stretch of river at the northern edge of the Nebraska Sand Hills. The mapped area includes the National Park Service unit of the Niobrara National Scenic River and the adjoining Middle Niobrara Preserve of The Nature Conservancy, and the Fort Niobrara Wildlife Refuge of the U.S. Fish and Wildlife Service. These digital geologic map data focus on the surficial geologic framework, dominated by the late Quaternary geology, of the Niobrara River valley corridor. These data are the result of geologic mapping begun by the U.S. Geological Survey in 2011 and continuing for about a decade. Mapping is based on geomorphic and other...
Several historic, multi-fault ruptures in the Eastern California Shear Zone (ECSZ) reinforce the need to understand how this rupture style contributes to seismic hazard in complex and diffuse fault zones. Several historic earthquakes in the ECSZ, the 1992 Landers, the 1999 Hector Mine, and the 2019 Ridgecrest rupture sequence, involved complex and multi-fault rupture. However, paleoseismic evidence of multi-fault ruptures in the ECSZ is poorly resolved in the rock record. Here I investigate paleoseismic evidence for complex rupture in Panamint Valley, located ~50 km northeast of the 2019 Ridgecrest ruptures. Late Holocene scarps in the 10 km-wide transtensional relay between the Ash Hill and Panamint Valley faults...
Categories: Data;
Tags: Ash Hill,
Eastern California Shear Zone,
Geomorphology,
Panamint Valley,
Southern California,
The Mammoth Springs (MS) fossil site at Hot Springs, South Dakota, provides a unique opportunity to reconstruct paleoenvironmental conditions. We used luminescence dating on fine sand sized potassium feldspars to establish a chronological framework for the site. In addition, we dated a late Pleistocene paludal proxy site using luminescence and incorporated those results with previous radiocarbon dating. Radiocarbon dating of the MS sinkhole organics suggested that the ages of the sediments that hosted the fossils was ~22-26 ka, while luminescence dating on feldspar grains suggested substantially older ages of ~130-255 ka. Analysis of the equivalent dose dispersion of the luminescence samples showed that the sediments...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Black Hills,
Climatology,
Fall River,
Geochemistry,
Geomorphology,
The following report summarizes the dating results from the. Within this report, we detail the methodology used to determine the storage time distribution for a 17 km length of Powder River in Montana, U.S.A. by the age distribution of eroded sediment. This data is used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and dating-related calculations. We recommend that this report be included as the supplementary material for any publication(s) that use the ages within this report. This version supersedes all previous age estimates and reports.
Categories: Data;
Tags: Fort Union Formation,
Geomorphology,
Kaycee Terrace,
Lightening Terrace,
Montana,
The following report summarizes the dating results from the San Luis Valley-Pioneer Fan 2017-2019 dating project. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and dating-related calculations. We recommend that this report be included as the supplementary material for any publication(s) that use the ages within this report.
Categories: Data;
Tags: Geomorphology,
Pioneer Fan,
San Luis Valley,
Sangre de Cristo Mountains,
Sedimentology,
The following report summarizes the dating results from the Natural Trap Cave 2018-2019 dating project. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and dating-related calculations. We recommend that this report be included as the supplementary material for any publication(s) that use the ages within this report. This version supersedes all previous age estimates and reports.
Categories: Data;
Tags: Big Horn County,
Big Horn Mountains,
Geochemistry,
Geomorphology,
Natural Trap Cave,
La Botica is positioned on a topographic bench sharply inset into the gentle eastern slope of the high San Juan Mountains and perched ~70-80 meters above La Jara Creek (fig. 1), a tributary to the Rio Grande. Quaternary surface processes have modified the Tertiary bedrock deposits that underlie La Botica to shape the physical environment. Bedrock deposits consist of Oligocene to Pliocene volcanic and sedimentary deposits related to the Rio Grande rift and the San Juan volcanic locus of the Southern Rocky Mountains volcanic field. Bedrock deposits are mildly deformed by normal faulting and eastward tilting related to the onset of extensional deformation in the Oligocene and formation of the San Luis Basin. Bedrock...
Categories: Data;
Tags: La Botica,
La Jara Creek,
Rio Grande,
San Juan Mountains,
South-Central Colorado,
The following report summarizes the dating results from Aeolian deposits within and around Edwards Air Force Base in California. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and dating related calculations. We recommend that this report be included as the supplementary material for any publication(s) that use the ages within this report. This version supersedes all previous age estimates and reports.
Categories: Data;
Tags: California,
Edwards Air Force Base,
Geochemistry,
Geomorphology,
Kern County,
The following report summarizes the dating results from sedimentary deposits exposed by soil pits in Panamint Valley, CA. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and dating-related calculations.
Categories: Data;
Tags: Ash Hill Fault,
Death Valley,
Eastern California Shear Zone,
Geochemistry,
Geomorphology,
This part of the data release contains sediment grain-size data for samples collected in eastern Chuckwalla Valley, Riverside County, California, in 2019 and 2020. Surface and sub-surface samples were analyzed for particle size in support of efforts to characterize landscape processes in areas permitted for future solar-energy development. These data accompany East and others (2021). Reference Cited: East, A.E., Gray, H.J., Redsteer, M.H., and Ballmer, M., 2021, Landscape evolution in eastern Chuckwalla Valley, Riverside County, California: U.S. Geological Survey Scientific Investigations Report 2021-5017, 46 p., https://doi.org/10.3133/sir20215017
Observations of widespread liquefaction and stratigraphic and structural relationships in a trench across an ambiguous scarp are used to constrain the timing of Holocene earthquakes on the northwest-striking Wallula fault zone in southeast Washington and Oregon. Additional observations and age constraints from OSL analysis of samples collected from large-scale liquefaction features that crosscut the Mount St Helens J tephra (13.8-13.7 ka) exposed at a nearby outcrop suggest up to 3 Holocene regional liquefaction events, any of which were likely triggered by seismic shaking sourced from either the Wallula fault and/or faults of the Yakima fold and thrust belt. Our observations provide plausible evidence supporting...
Categories: Data;
Tags: Columbia Plateau,
Columbia River,
Geochemistry,
Geomorphology,
Sedimentology,
Geochronologic and isotopic data for Paleohydrologic history of Pluvial Lake San Agustin, New Mexico
This dataset includes tables of radiocarbon, uranium thorium series, and luminescence geochronologic ages and stable carbon and oxygen isotope compositions for sedimentary and organic samples.
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