Filters: Tags: Focused Assessments (X) > partyWithName: U.S. Geological Survey (X)
8 results (30ms)|
Filters
Date Range
Contacts
Categories Tag Types
|
This child item contains ground penetrating radar (GPR) data collected over a small alpine wetland between Mogul Mine and Cement Creek located near Silverton, Colorado. Mine-impacted water is transported to Cement Creek via surface channels and groundwater through this wetland. The GPR method transmits radar pulses into the ground and measures the returned amplitude from these pulses over time. Variations in subsurface electromagnetic (EM) properties (dielectric permittivity, electrical conductivity, and magnetic susceptibility) affect the timing and amplitude of returned radar energy. For example, variation in water or mineral content are physical properties that often influence the EM properties that are observed...
This child item contains self-potential (SP) data collected over a small alpine wetland between Mogul Mine and Cement Creek located near Silverton, Colorado. Mine-impacted water is transported to Cement Creek via surface channels and groundwater through this wetland. The SP method measures passive voltages in the subsurface using a high impedance voltmeter with one fixed electrode at a base station and one mobile electrode. Strong self-potential anomalies have been associated with ore bodies and sharp redox fronts. Data were collected with an Agilent U1252B multimeter with STELTH3 Ag-AgCl Model SRE-011-SPB porous pot electrodes. Additional details are contained in the ‘readme.txt’ file within this directory.
This child item contains frequency domain electromagnetic induction (FDEM) data collected along and around Cement Creek California Gulch, and the Animas River near Silverton, Colorado in support of other data collected at the site. The FDEM tool generates an EM field and measures eddy currents generated by conductive and/or magnetic materials in the subsurface in response to the applied field. A Geophex GEM-2 instrument with GPS was used with frequencies ranging from 450 Hz to 47970 Hz. Additional details are contained in the ‘readme.txt’ files within each zip data directory.
This child item contains magnetometer (MAG) data collected along and around the Animas River near Silverton, Colorado in support of other data collected at the site. The MAG tool measures the magnetic field from one or multiple sensors. A Geometrics G-858AP instrument with GPS and backpack was used, with two magnetometers vertically mounted on the operator-carried staff to enable measurement of the magnetic field gradient. Additional details are contained in the ‘readme.txt’ files within each zip data directory.
Near-surface geophysical data from within the Bonita Peak Mining District in Silverton, Colorado, USA are presented. These data were collected in 2019. The data include fiber optic distributed temperature sensing (FO-DTS) and frequency domain electromagnetic induction (FDEM) data collected in and around roughly 1 km reaches of Cement Creek and California Gulch. Additional data, including ground penetrating radar (GPR) and self potential (SP), were gathered from a peatland that intercepts acid mine drainage from Mogul Mine into Cement Creek. The peatland is located off the eastern bank of Cement Creek in the northern portion of the reach surveyed with FO-DTS and FDEM. In 2021, an FO-DTS, FDEM, and magnetometer (MAG)...
Categories: Data Release - Revised;
Tags: Animas River,
California Gulch,
Cement Creek,
Colorado,
Focused Assessments,
This child item contains fiber-optic distributed temperature sensing (FO-DTS) data collected along the streambed interface of two streams named Cement Creek and California Gulch Creek, as well as the Animas River, located near Silverton Colorado. The FO-DTS method utilizes the temperature-dependent backscatter of light pulses emitted along armored fiber-optic cables to evaluate temperature at discrete linear sampling locations. For these deployments a Salixa XT-DTS control unit (Salixa Ltd, Hertfordshire, UK) was used, and measurements were made over several day increments at 0.508 m linear resolution along the streambed interface. Specific locations for collected data are located within the data files, and additional...
The National Crude Oil Spill Fate and Natural Attenuation Research Site is located near Bemidji, MN, USA. A high-pressure oil pipeline ruptured in 1979 releasing ~1.7 million liters of light crude oil, which sprayed over an area of ~6500 square meters and collected in topographic depressions. Approximately 75% of the spilled oil was recovered. Much of the remainder reached the water table, where it is distributed into three residual oil bodies (the north, middle, and south oil pools). Groundwater flows east-northeast toward a small lake roughly 300 m downgradient from the original spill site. Secondary reactions of sediments with byproducts from anaerobic degradation of the oil plumes cause increases in total dissolved...
Categories: Data Release - Revised;
Tags: Ambient Monitoring,
Bemidji,
Focused Assessments,
Geophysics,
Geophysics,
This data release contains phytoplankton classification and enumeration results from two moving boat surveys conducted on July 15 - 18, 2019 and August 19 - 22, 2019. These data were collected from the Caloosahatchee River and estuary, the St. Lucie River and estuary, and Lake Okeechobee with funding provided by the USGS Priority Ecosystems Greater Everglades Program.
Categories: Data;
Tags: Caloosahatchee Canal,
Caloosahatchee River,
Ecosystem Health,
Ecosystem Health,
Florida,
|
|
