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Karst systems are useful for examining spatial and temporal variability in Critical Zone processes because they provide a window into the subsurface where waters have interacted with vegetation, soils, regolith, and bedrock across a range of length and time scales. The majority of Critical Zone research has emphasized silicate lithologies, which are typified by relatively slow rates of reactivity and incongruent weathering. However, weathering of carbonate dominated lithology can result in secondary mineral deposits, such as speleothems, which provide a long-term archive for Critical Zone processes. Examination of carbon isotope variability in speleothems has the potential to provide records of changes in vegetation,...
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Alamagan Volcano is a Quaternary stratovolcano along the Mariana Arc, an active subduction zone in the western Pacific Ocean. Although primarily submerged, its peak reaches above sea level, with subaerially-exposed volcanic deposits dating back through the Holocene to the late Pleistocene. These feature data represent such deposits and other geologic features of Alamagan Volcano, describing its interpreted eruptive history.
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Continuous monitoring and discrete water-quality sampling were coupled in a karst aquifer to assess drivers and timescales of water-quality change. Water-quality data included environmental tracers of groundwater age (tritium [3H], tritiogenic helium-3 [3He-trit], sulfur hexafluoride [SF6], carbon-14 [14C], and radiogenic helium-4 [4He-rad]). All water quality data is available from the U.S. Geological Survey NWIS database (U.S. Geological Survey, 2019). Groundwater ages were estimated by calibration of environmental tracers to lumped parameter models of groundwater age for multiple samples collected at six groundwater wells using the program TracerLPM (Jurgens and others, 2012). The final estimates for mean groundwater...
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The storage and persistence of soil organic matter (SOM) is of critical importance to soil health, and to the terrestrial carbon cycle with implications for long-term climate change. To better understand the spatio-temporal controls on SOM, we have developed a new dataset spanning two previously described marine terrace soil chronosequences from northern, CA, USA: the Santa Cruz and the Mattole River chronosequences. Each of these sites, is comprised of several terraces surfaces that span at least 200 ka of soil development. The sites differ with regard to local precipitation, with the Mattole site receiving nearly double the mean annual precipitation of the Santa Cruz site. During the period from 2011 through 2016,...
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The Weldona 7.5' quadrangle is located on the semiarid plains of northeastern Colorado, along the South Platte River corridor where the river has incised into Upper Cretaceous Pierre Shale. The Pierre Shale is largely covered by surficial deposits that formed from alluvial, eolian, and hillslope processes operating in concert with environmental changes from the Pleistocene to the present. The South Platte River, originating high in the Colorado Rocky Mountains, has played a major role in shaping surficial geology in the map area, which is several tens of kilometers downstream from where headwater tributaries join the river. Recurrent glaciation (and deglaciation) of basin headwaters has affected river discharge...
Our objective is to develop improved integration of data and models of soil and ecosystem processes at the regional scale in order to better quantify change in response disturbances, particularly drought. Specifically, we synthesize existing and generate new datasets of soil properties of soils form the Upper Colorado River Basin region of the Western US. Data types include geospatial databases and maps; soil physical, chemical, and biological datasets; soil hydrologic data; stream and river chemistry associated with regional mapping of soils; model input parameterizations and output data.
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The Fort Morgan 7.5' quadrangle is located on the semiarid plains of northeastern Colorado, along the South Platte River corridor where the river has incised into Upper Cretaceous Pierre Shale. The Pierre Shale is largely covered by surficial deposits that formed from alluvial, eolian, and hillslope processes operating in concert with environmental changes from the late Pliocene to the present. The South Platte River, originating high in the Colorado Rocky Mountains, has played a major role in shaping surficial geology in the map area, which is several tens of kilometers downstream from where headwater tributaries join the river. Recurrent glaciation (and deglaciation) of basin headwaters has affected river discharge...
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Mammoth Mountain is a dacitic dome complex located on the southwestern rim of Long Valley Caldera, California. Mammoth Mountain has exhibited unrest over the past ~30 years, characterized by seismicity over a broad range of depths, elevated 3He/4He ratios in fumarolic gas and large-scale diffuse CO2 emissions. Monitoring of this unrest has included collection of fumarole gas samples for geochemical analysis and tree cores for radiocarbon analysis of annual growth rings. This report updates the long-term geochemical record at Mammoth Mountain, compiling the chemical and isotopic (d13C-CO2, 3He/4He) compositions of 59 gas samples collected from Mammoth Mountain fumarole from 1998 to 2016. In addition, we report radiocarbon...
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This data release documents two Microsoft Excel tables that contain data for understanding tracer concentrations and groundwater age in the Columbia Plateau aquifer system. Results for geochemical correction of carbon-14, and lumped parameter modeling of groundwater age for the sample network (VPFS, vertical flow path study) are described. Geochemical carbon-14 correction results (RFG) describe geochemical correction of carbon-14 in dissolved inorganic carbon (DIC) for groundwater age dating. Datasets includes measured water parameters and chemistry, model parameter inputs, and final corrected carbon-14 in DIC. Geochemical correction was completed using the revised Fontes and Granier model of Han and Plummer (2013)....
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In the past century, eruptions of Steamboat Geyser in Yellowstone’s Norris Geyser Basin were mainly clustered in three episodes: between 1961 and 1969, between 1982 and 1984, and in a sequence of eruptions that began in 2018 (Reed et al., 2021) and resulted in extensive damage to, and mortality of the surrounding trees. To characterize tree response to geyser activity over time, and the response of geyser activity to climate variability, aerial and ground imagery were analyzed to document changes in tree coverage around the geyser since 1954. Twenty samples of silicified tree remnants were collected from near the geyser vent for radiocarbon (14C) dating to determine if trees grew during periods when the geyser was...
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This data release contains radiocarbon dates and clumped isotope ratios for soil carbonates as well as observed soil temperatures for study sites in the San Luis Valley, Colorado and New Mexico, USA. The companion publication can be found at https://doi.org/10.1029/2023GC011221.
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In conjunction with geologic mapping of four 7.5′ quadrangles along the South Platte River corridor in northeastern Colorado (Masters, Orchard, Weldona, and Fort Morgan), geochronology samples were collected and analyzed using optically stimulated luminescence (OSL), radiocarbon (14C), or U-series methods to provide age control for mapping units. This section of river corridor is largely covered by surficial deposits that formed from alluvial, eolian, and hillslope processes operating in concert with environmental changes from the Pleistocene to the present. The South Platte River originates high in the Colorado Rocky Mountains and recurrent glaciation of basin headwaters has affected river discharge and sediment...
The reliability of lichenometric dating is dependent on a good understanding of lichen growth rates. The growth rate of lichens can be determined from direct measurement of growing lichens or indirect methods by measuring lichens growing on surfaces of known age, although there are limitations to both approaches. Radiocarbon (14C) analysis has previously been used in only a handful of studies to determine lichen growth rates of two species from a small area of North America. These studies have produced mixed results; a small amount of carbon turnover appears to occur in one of the species (Caloplaca spp.) previously investigated introducing uncertainty in the growth rate, while much higher carbon cycling occurred...
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This data release includes multiple datasets obtained during the study of north-facing fault scarps along the Seattle fault zone. It includes geochronological data and field measurements from the Vasa Park trench (47.576618°, -122.119524°) near Bellevue, WA, and the Rose Hip trench (47.597°, -122.535°), Lyle Beach terrace site (47.597,-122.542), and Mill Pond site (47.597,-122.525) on south Bainbridge Island, WA. This data release also contains ground-based geomagnetic data of multiple transects across the Seattle fault zone on south Bainbridge Island and Point Glover.
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This data release documents four tables that contain data for assessing the susceptibility of groundwater using environmental tracers collected from public-supply wells located in the Northern Atlantic Coastal Plain (NACP) Aquifer System and Piedmont and Blue Ridge Crystalline-Rock Aquifers of Eastern United States. Results for two modeling support studies located within the NACP are also included. Table 1 provides the primary results of this study and it contains condensed results from dissolved gas modeling and calculated environmental tracer concentrations, as well as results of the tritium age classification, susceptibility index, the mean groundwater age, fraction of Modern water (water that was recharged after...
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Stabilization of SOM (soil organic matter) is regulated in part by sorption and desorption reactions happening at mineral surfaces, as well as precipitation and dissolution of organo-metal complexes. Fe and Al hydroxides play a particularly significant role in SOM stabilization in soils due to their ubiquitous distribution and their highly reactive surface properties. Iron and Al hydroxides exist in soils across a wide spectrum of crystallinity, ranging from dissolved Fe and Al cations which combine with organics to form organo-metal precipitates to the more crystalline end members, goethite and gibbsite, which sorb SOM through a variety of molecular interactions. Though the importance of these sorption and precipitation...
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This data release includes the MATLAB code used for sensitivity analysis of turbidite age estimates along the Cascadia subduction zone. The code is written for use in MATLAB and datasets are organized as .mat files. Data values are from Goldfinger et al. (2012) and Staisch (2024). Cited works: Goldfinger, C., Nelson, C.H., Morey, A.E., Johnson, J.E., Patton, J.R., Karabanov, E., Gutiérrez-Pastor, J., Eriksson, A.T., Gràcia, E., Dunhill, G., Enkin, R.J., Dallimore, A., and Vallier, T., 2012, Turbidite event history—Methods and implications for Holocene paleoseismicity of the Cascadia subduction zone: U.S. Geological Survey Professional Paper 1661–F, 170 p. (Available at https://pubs.usgs.gov/pp/pp1661f/). Staisch,...
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This data release documents seven tables that contain environmental tracer data and lumped parameter model (LPM) results that are used for assessing the distribution of groundwater age in 21 Principal Aquifers of the continental United States. Groundwater samples were collected from 1,279 sites and analyzed for environmental tracers: tritium, tritiogenic helium-3, sulfur hexafluoride, carbon-14, and radiogenic helium-4. For each sample, groundwater age distributions were estimated by fitting LPMs to the environmental tracers using the computer program TracerLPM (Jurgens and others, 2012). Calibrated lumped parameter models provide the optimal distribution of ages in a sample that explain the measured concentrations...
Categories: Data Release - Revised; Tags: Alabama, Arizona, Arkansas, Basin and Range basin-fill aquifers (BNRF), Basin and Range carbonate-rock aquifers (BNRC), All tags...


    map background search result map search result map Data release for the geologic map of the Weldona 7.5' quadrangle, Morgan County, Colorado Data release of OSL, 14C, and U-series age data supporting geologic mapping along the South Platte River corridor in northeastern Colorado Data release for the geologic map of the Fort Morgan 7.5' quadrangle, Morgan County, Colorado Data for Assessing the Susceptibility of Groundwater Using Environmental Tracers in Northern Atlantic Coastal Plain Aquifer System and Piedmont and Blue Ridge Crystalline-Rock Aquifers of Eastern United States Fumarole gas geochemistry and tree-ring radiocarbon data at Mammoth Mountain, California (1989-2016) Data for timescales of water-quality change in a karst aquifer, south-central Texas Lumped parameter models of groundwater age from the Columbia Plateau Aquifer, Vertical Flowpath Study Network Isotopic, geochronologic and soil temperature data for Holocene and late Pleistocene soil carbonates of the San Luis Valley, Colorado and New Mexico, USA Soil Biogeochemical Data from a Marine Terrace Soil Climo-Chronosequence Comparison Alamagan Volcano - geochronologic points Data from a reactive transport modeling study of cave seepage water chemistry Data for Distribution of Groundwater Age in Aquifers Used for Public Supply in the Continental United States, 2004 - 2017 (Version 1.1: June 2022) Radiocarbon dating of silicified wood from around Steamboat Geyser in Norris Geyser Basin, Yellowstone National Park, 2021-2022 Nearshore Fish Isotope Values, Beaufort Sea, Alaska, 2017-2019 Monte Carlo code for manuscript: Sensitivity testing of marine turbidite age estimates along the Cascadia Subduction Zone Radiocarbon, field measurements, and ground-based magnetic transect data supporting the study of north-facing scarps along the Seattle fault zone in Washington Data from a reactive transport modeling study of cave seepage water chemistry Alamagan Volcano - geochronologic points Fumarole gas geochemistry and tree-ring radiocarbon data at Mammoth Mountain, California (1989-2016) Radiocarbon, field measurements, and ground-based magnetic transect data supporting the study of north-facing scarps along the Seattle fault zone in Washington Data release for the geologic map of the Weldona 7.5' quadrangle, Morgan County, Colorado Data release for the geologic map of the Fort Morgan 7.5' quadrangle, Morgan County, Colorado Data release of OSL, 14C, and U-series age data supporting geologic mapping along the South Platte River corridor in northeastern Colorado Data for timescales of water-quality change in a karst aquifer, south-central Texas Nearshore Fish Isotope Values, Beaufort Sea, Alaska, 2017-2019 Soil Biogeochemical Data from a Marine Terrace Soil Climo-Chronosequence Comparison Lumped parameter models of groundwater age from the Columbia Plateau Aquifer, Vertical Flowpath Study Network Monte Carlo code for manuscript: Sensitivity testing of marine turbidite age estimates along the Cascadia Subduction Zone Data for Assessing the Susceptibility of Groundwater Using Environmental Tracers in Northern Atlantic Coastal Plain Aquifer System and Piedmont and Blue Ridge Crystalline-Rock Aquifers of Eastern United States Data for Distribution of Groundwater Age in Aquifers Used for Public Supply in the Continental United States, 2004 - 2017 (Version 1.1: June 2022)