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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.
The Ziegler Reservoir fossil site near Snowmass Village, Colorado (USA) provides a rare opportunity to examine environmental conditions in the Rocky Mountains during marine isotope stage (MIS) 4 (71–57 ka). Although recognized as a global-scale cold event, MIS 4 is typically absent from Rocky Mountain glacial chronologies because the geologic evidence was either covered or destroyed during the subsequent, and larger, MIS 2 (Pinedale; 29–14 ka) glaciation. The Ziegler Reservoir site is perched on a ridge above Pinedale glacial limits, which allowed for the preservation of a long-lived sequence of predominantly eolian sediments that spans from late MIS 6 (ca. 140 ka) through early MIS 3 (ca. 55 ka). Sediments dating...
Categories: Data;
Tags: Climatology,
Rocky Mountains,
Rocky Mountains,
Snowmass Village, Colorado,
USGS Science Data Catalog (SDC),
Human footprints at White Sands National Park, New Mexico, USA, reportedly date to between ~23,000 and 21,000 years ago according to radiocarbon dating of seeds from the aquatic plant Ruppia cirrhosa. These ages remain controversial because of potential old carbon reservoir effects that could compromise their accuracy. We present new calibrated 14C ages of terrestrial pollen collected from the same stratigraphic horizons as those of the Ruppia seeds, along with optically stimulated luminescence ages of sediments from within the human footprint–bearing sequence, to evaluate the veracity of the seed ages. The results show that the chronologic framework originally established for the White Sands footprints is robust...
Categories: Data;
Tags: Chihuahuan Desert,
Last Glacial Maximum,
New Mexico,
Paleolake Otero,
USGS Science Data Catalog (SDC),
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.
Archaeologists and researchers in allied fields have long sought to understand human colonization of North America. Questions remain about when and how people migrated, where they originated, and how their arrival affected the established fauna and landscape. Here, we present evidence from excavated surfaces in White Sands National Park (New Mexico, United States), where multiple in situ human footprints are stratigraphically constrained and bracketed by seed layers that yield calibrated radiocarbon ages between ~23 and 21 thousand years ago. These findings confirm the presence of humans in North America during the Last Glacial Maximum, adding evidence to the antiquity of human colonization of the Americas and providing...
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,
We assessed a construction site in the northern Las Vegas Valley that was initially reported as an "ice age" deposit. Alluvial deposits exposed at the site were inset into the Las Vegas Formation and contained semi-articulated Equus remains. Calibrated radiocarbon dates on two different materials associated with the remains centered on 1957, thus rendering the horse bones as modern.
Categories: Data;
Tags: Climatology,
Equus,
Las Vegas Valley,
Nevada,
USGS Science Data Catalog (SDC),
The late Pleistocene was a climatically dynamic period, with abrupt shifts between cool-wet and warm-dry conditions. Increased effective precipitation supported large pluvial lakes and long-lived spring ecosystems in valleys and basins throughout the western and southwestern U.S., but the source and seasonality of the precipitation are debated. Here we present stable carbon and oxygen isotope data from tooth enamel of late Pleistocene herbivores recovered from paleowetland deposits at Tule Spring Fossil Beds National Monument in the Las Vegas Valley of southern Nevada, as well as modern herbivores from the surrounding area, to investigate whether winter or summer precipitation was responsible for driving the wet...
Climate in the southeastern U.S. is predicted to be changing at a slower rate than other parts of North America; however, land use change associated with urbanization is having a significant effect on wildlife populations and habitat availability. We sought to understand the effect of global warming on both beneficial and pest insects of trees. We used urban warming as a proxy for global warming in as much as many cities have already warmed as much, due to heat island effects, as they are expected to warm due to climate change by 2050 or even 2100. We were able to develop good predictive models of how warming influences beneficial and pest insects for cities in the Southeast and across the east coast more generally....
Categories: Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2011,
Baltimore City,
Boundary,
CASC,
Climate Change,
A raster dataset representing slope in the conterminous United States. This dataset was created from the radian slope raster of 100-meter spatial resolution developed by Ramcharan et al. (2018). Those data were derived from a conterminous 100-m Digital Elevation Model (DEM) for the United States (http://nationalmap.gov/) using SAGA GIS software. Slope values are put into 9 slope classes to facilitate interpretation and reporting. Ramcharan, A., Hengl, T., Nauman, T., Brungard, C., Waltman, S., Wills, S., and Thompson, J., 2018, Soil Property and Class Maps of the Conterminous United States at 100-Meter Spatial Resolution: Soil Science Society of America Journal, v. 82, p. 186-201. http://dx.doi.org/10.2136/sssaj2017.04.0122.
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 Eglington fault is one of several intrabasinal faults in the Las Vegas Valley, Nevada, USA, and is the only one recognized as a source for significant earthquakes. Its broad warp displaces Late Pleistocene spring deposits of the Las Vegas Formation, which record hydrologic fluctuations that occurred in response to millennial- and submillennial-scale climate oscillations throughout the late Quaternary. The sediments allow us to constrain the timing of displacement on the Eglington fault and identify hydrologic changes that are temporally coincident with that event. The fault deforms deposits that represent widespread marshes that filled the valley between ca. 31.7 and 27.6 ka. These marshes desiccated abruptly...
Categories: Data;
Tags: Climatology,
Eglington fault,
Geomorphology,
Hydrology,
Las Vegas Formation,
This dataset is North American Breeding Bird Survey bird-count data for the routes and stops in North Dakota, USA, in which ten mixed-grass-prairie-endemic species occurred, as well as the mean habitat-quality ranking scores derived from applying the Habitat Quality Module of the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) to spatial layers for landuse/landcover from the National Agricultural Statistics Survey, CRP from USDA, urban and road areas from US Census Bureau (Tiger/Line), and energy development from USGS. The bird-count data is the total sum of counts for the focal ten species; individual species counts are not part of the dataset.
Categories: Data;
Tags: North Dakota,
Prairie Pothole Region,
USGS Science Data Catalog (SDC),
biota,
birds,
Recent studies have shown the oxygen isotopic composition (δ18O) of modern terrestrial gastropod shells is determined largely by the δ18O of precipitation. This implies that fossil shells could be used to reconstruct the δ18O of paleo-precipitation as long as the hydrologic pathways of the local watershed and the shell isotope systematics are well understood. In this study, we measured the δ18O values of 456 individual gastropod shells collected from paleowetland deposits in the San Pedro Valley, Arizona that range in age from ~29.1 to 9.8 ka. Isotopic differences of up to 2‰ were identified between the four taxa analyzed (Succineidae, Pupilla hebes, Gastrocopta tappaniana, and Vallonia gracilicosta), with Succineidae...
Categories: Data;
Tags: Climatology,
Geochemistry,
Murray Springs Paleoindian Site,
Murray Springs Paleoindian Site,
San Pedro Valley,
This release contains avaialable particle-size and mineralogic data as well as latitude and longitude information for dust samples collected from snow at high elevation sites in the Colorado Rocky Mountains and from dust source areas on the Colorado Plateau.
Categories: Data;
Tags: Climatology,
Colorado Plateau,
Colorado Rocky Mountains,
Geomorphology,
Land Use Change,
The Younger Dryas (YD) climate event is the preeminent example of abrupt climate change in the recent geologic past. Climate conditions during the YD were spatially complex, and high-resolution sediment cores in the North Atlantic, western Europe, and East Asia have revealed it unfolded in two distinct stages, including an initial stable climatic period between ~12.9 and 12.2 ka associated with a weakened Atlantic Meridional Overturning Circulation (AMOC) and a second phase characterized by variable conditions until 11.7 ka as the AMOC recovered. Decades of investigations into the climate of western North America during the YD have failed to identify this stepped phenomenon. Here we present hydroclimate data from...
The present study investigates the environmental significance of the oxygen isotopic composition of several modern land snail species collected along two north-to-south transects in Alaska and Scandinavia at latitudes between 60 and 70 °N. We tested the hypothesis that land snail shell δ18O values primarily track precipitation δ18O. The results show that shell δ18O values from Scandinavia were ~5.1‰ enriched in 18O with respect to snails from Alaska, equivalent to differences in precipitation δ18O values between the two regions. Within the Alaskan transect, shell δ18O values increased with observed increasing air temperature and precipitation δ18O, whereas shell δ18O values from Scandinavia did not correlate to...
Categories: Data;
Tags: Alaska,
Climatology,
Scandinavia,
USGS Science Data Catalog (SDC),
calibration,
The Las Vegas Formation (LVF) is a well-characterized sequence of groundwater discharge (GWD) deposits exposed in and around the Las Vegas Valley in southern Nevada. Nearly monolithologic bedrock surrounds the valley and provides an excellent opportunity to test the hypothesis that GWD deposits include an aeolian component. Mineralogical data indicate that the LVF sediments are dominated by carbonate minerals, similar to the local bedrock, but silicate minerals are also present. The median particle size is ~35 µm, consistent with modern dust in the region, and magnetic properties contrast strongly with local bedrock, implying an extralocal origin. By combining geochemical data from the LVF sediments and modern dust,...
Categories: Data;
Tags: Desert Wetlands,
Geochemistry,
Hydrology,
Las Vegas Formation,
Las Vegas, Nevada,
The GIS shapefile and summary table provide irrigated agricultural land-use for Okeechobee County, Florida through a cooperative project between the U.S Geological Survey (USGS) and the Florida Department of Agriculture and Consumer Services (FDACS), Office of Agricultural Water Policy. Information provided in the shapefile includes the location of irrigated land field-verified between November 2016 and September 2017, crop type, irrigation system type, and primary water source used in Okeechobee County, Florida. A map image of the shapefile is provided in the attachment.
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Florida,
USGS Science Data Catalog (SDC)
The isotopic values of fossil snail shells can be important archives of past climate. Here we present the first carbon (δ13C) and oxygen (δ18O) isotope values of radiocarbon-dated and live-collected snails in interior Alaska to explore changes in vegetation and humidity through the late glacial period (14-11.7 ka). Snail shell δ13C values were relatively consistent through the late glacial. However, late glacial shell δ13C values are 2.8‰ higher than modern shells. This offset is best explained by changes in the δ13C values of plants consumed by snails. Snail shell δ18O values varied through the late glacial, which can be partially explained by changes in relative humidity (RH). RH during the snail growing period...
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