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DC Resitivity Methodology Direct current (DC) resistivity transects were surveyed using an IRIS Syscal Pro Switch 96 instrument (IRIS Instruments, Inc., Orléans, France). Steel electrodes were hammered into the ground at a fixed distance along the profile. These were connected to the instrument using copper wires and junction boxes. The number of electrodes on each profile and their spacing is shown below: Line 1: 180 electrodes, 5 meter spacing Line 2: 48 electrodes, 2 meter spacing Line 3: 48 electrodes, 2 meter spacing Line 4: 24 electrodes, 2 meter spacing Line 5: 36 electrodes, 2 meter spacing On Line 1, the roll-along method was used to extend the line to its full extent. In this method, 48 electrodes...
Categories: Data
Lake Poinsett is a 260-hectare (640 acres) lake located on Crowley’s Ridge in northeastern Arkansas, approximately 6 km southeast of Harrisburg, Arkansas within Poinsett County. The lake was built for recreation by the Arkansas Highway Department in 1960 by constructing a roughly 800-meter dam across the southern boundary of the Distress Creek watershed. The dam is currently operated by the Arkansas Game and Fish Commission (AGFC). AGFC and Arkansas Natural Resources Commission (ANRC) plan to drain the lake to allow access for a series of bank stabilization and dam safety improvements. Because none of the original blueprints exist, AGFC asked the U.S. Geological Survey (USGS) to conduct a series of differential...
Categories: Data;
Tags: Arkansas,
Crowley's Ridge,
Electrical Resistivity,
Frequency Domain Electromagnetics,
GNSS Survey,
FDEM Methodology For this project frequency domain electromagnetic (FDEM) data were collected with a GEM-2, a broadband, multifrequency, fixed-coil electromagnetic induction unit (Geophex, 2015). Both in-phase and quadrature data were collected on 15 channels from a frequency of 810 Hz to 66,090 Hz. This system was carried along profiles that followed the axis of the dam and along tie lines that were perpendicular to the axis of the dam. Each data point was located using a backpack mounted GPS. To correct the drift of the instrument, a base station was established on the east side of the dam. Each survey started and ended with an occupation of the base station. These occupations occur as even line numbers...
Categories: Data
The activities associated with the construction of a new walkway within Mammoth Cave caused vibrations to be felt in the cave, which is home to an endangered Indiana bat roost. These data were collected at the request of the National Park Service to monitor the vibration levels near a bat roost within Mammoth Cave National Park to determine if construction-induced vibration might be inducing the observed activity of the bats. Seven geophones and two accelerometers were placed in the passage to the bat roost to monitor the distribution of ground velocity and acceleration. The vibration signature of individual construction equipment (jackhammer, place compactor, and hammer drill), human activities during a simulated...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Kentucky,
Mammoth Cave National Park,
United States,
ground vibrations
Airborne geophysical surveys were acquired in March 2018 and May 25 through August 7, 2021 using a helicopter-based platform. These surveys were collected along 10,706 line-kilometers (line-km) within selected areas of the Mississippi Alluvial Plain (MAP) and the Chicot Aquifer System in the southeastern United States. The airborne geophysical surveys include electromagnetic, magnetic, and radiometric sensor data collected in rivers and levees throughout the two areas to evaluate groundwater and surface-water interaction, riverine ecosystems, and infrastructure. This data release contains three child items that provide: Minimally processed (raw) data supplied by the airborne contractor (Xcalibur Multiphysics)...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: "Geomorphology"],
"Hydrology",
"Sedimentology",
"Stratigraphy",
"Water Resources",
Water pressure, ground velocity and ground acceleration data were collected May 19-22, 2014 at Brandon Road Lock and Dam near Joliet, Illinois and also June 2-5, 2014 in the Chicago Sanitary and Ship Canal near Lemont, Illinois. The data were collected to measure water pressures and ground velocities produced from the firing of a seismic water gun.
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: USGS Science Data Catalog (SDC)
GNSS Method A benchmark monument was set at each end of the earthen dam in accordance with (U.S. Army Corps of Engineers, 2002). A level II survey (Rydlund & Densmore 2012) was conducted on each monument to establish control. Two 4-hour observations were conducted with a staggered approach for each monument, with one 4-hour session in the morning of the first day and one 4-hour session in the afternoon of the second day. Once elevational control was established, a Real Time Kinematic (RTK) system was set up with base on the monument that had the best observations. Using this system, a point cloud survey was conducted along the top and face of the dam using both a monopod and an All-Terrain Vehicle. A Global...
Categories: Data
FDEM Processing The frequency domain electromagnetic (FDEM) data were downloaded from the GEM-2 instrument and aggregated into a single data file. The data were manually despiked and smoothed to remove negative values and the effects of metallic objects. A drift correction was applied by finding the average in-phase and average quadrature values for each frequency transmitted each time the base station was occupied. This average value was then used to calculate a linear trend of the data in time and the linear trend was subtracted from the data set. After the data were drift corrected, the data was leveled by calculating the arithmetic mean of the survey data subtracting that value from the dataset to level...
Categories: Data
Surface and water-borne geophysical methods can provide information for the characterization of the subsurface structure of the earth for aquifer investigations. Floating and towed transient electromagnetic (FloaTEM and tTEM) surveys provide resistivity soundings of the subsurface, which can be related to lithology and hydrogeology. In the TEM method, a primary electrical current is cycled through a wire in a transmitter loop (Tx), which in turn produces a static primary magnetic field. When the current in the TX loop is abruptly terminated, secondary electrical currents are induced in the earth that move downward and outward decaying with time. The decay of the secondary electrical field is controlled by the subsurface...
This data release consists of three different types of data: including direct current (DC) resistivity profiles, frequency domain electromagnetic (FDEM) survey data, and global navigation satellite system (GNSS) coordinate data of the geophysical measurement locations. A data dictionary is included along with the data and defines all of the table headings, definitions, and units. Earthen dams are common on lakes and ponds, but characteristics of these structures such as construction history, composition, and integrity are often unknown for older dams. Geophysical surveying techniques provide a non-invasive method of mapping their lithology and structure. In particular, DC resistivity and FDEM methods can,...
Categories: Data;
Tags: Arkansas,
Bob Kidd Lake,
Direct current resistivity,
Earthen dam,
Earthen structure,
FDEM Methodology For this project frequency domain electromagnetic (FDEM) data were collected with a GEM-2, a broadband, multifrequency, fixed-coil electromagnetic induction unit (Geophex, 2015). Both in-phase and quadrature data were collected on 15 channels from a frequency of 810 Hz to 66,090 Hz. This system was carried along profiles that followed the axis of the dam and along tie lines that were perpendicular to the axis of the dam. Each data point was located using a backpack mounted GPS. To correct the drift of the instrument, a base station was established on the east side of the dam. Each survey started and ended with an occupation of the base station. These occupations occur as even line numbers...
Categories: Data
Karst environments present many challenges to agencies and engineers attempting to work in these landscapes, particularly towards building infrastructure. The interconnectivity of karst hydrologic systems means that activities occurring on the surface of a karst landscape can have an impact on water quality and quantity. Additionally, soil thickness in karst landscape is often highly variable due to the presence of solutionally-enlarged fractures, joints, and openings at the soil-bedrock interface. Therefore, when planning infrastructure in karst terrains it is critical to do a thorough assessment to ensure that planned activities will not negatively impact the sensitive environment. In October 2020 Electric Resistivity...
The activities associated with the construction of a new walkway within Mammoth Cave caused vibrations to be felt in the cave, which is home to an endangered Indiana bat roost. These data were collected at the request of the National Park Service to monitor the vibration levels near a bat roost within Mammoth Cave National Park to determine if construction-induced vibration might be inducing the observed activity of the bats. Seven geophones and two accelerometers were placed in the passage to the bat roost to monitor the distribution of ground velocity and acceleration. The vibration signature of individual construction equipment (jackhammer, place compactor, and hammer drill), human activities during a simulated...
DC Resitivity Methodology Direct current (DC) resistivity transects were surveyed using an IRIS Syscal Pro Switch 96 instrument (IRIS Instruments, Inc., Orléans, France). Steel electrodes were hammered into the ground at a fixed distance along the profile. These were connected to the instrument using copper wires and junction boxes. The number of electrodes on each profile and their spacing is shown below: Line 1: 180 electrodes, 5 meter spacing Line 2: 48 electrodes, 2 meter spacing Line 3: 48 electrodes, 2 meter spacing Line 4: 24 electrodes, 2 meter spacing Line 5: 36 electrodes, 2 meter spacing On Line 1, the roll-along method was used to extend the line to its full extent. In this method, 48 electrodes...
Categories: Data
This data release consists of two .csv files of inverted models of electrical resistivity created from the processed resistivity data in the accompanying two data releases: (Miller and Others, 2018) and (2018 Raw and Processed, in progress). During 2016, 17, and 18, the U.S. Geological Survey conducted continuous resistivity profiling along 15 rivers or lakes in the Mississippi Alluvial Plain of Mississippi, Arkansas, Louisiana, and Missouri to characterize streambed hydraulic conductivity values. These techniques characterize the near surface geomorphology of the streambed that controls the recharge to the alluvial aquifer. These data can be used to map changes in the lithology of the streambed and identify areas...
Categories: Data;
Types: ArcGIS REST Map Service,
ArcGIS Service Definition,
Downloadable,
Map Service;
Tags: Arkansas,
Black River,
Bogue Phalia,
Cache River,
Continuous Resistivity Profiling,
DC Resistivity Processing Data were imported into the Workbench Electrical Resistivity Tomography Module (Aarhus Geophysical, Inc.; version 5.5.0.0) using the “Syscal” data import options. The data were then manually despiked and any negative resistivity values were removed. The data were subsequently inverted using “Aarhus 2D” inversion option. The “Smooth” Inversion setting was chosen with model converging to the L2 norm. The number of layers of the starting model was set to 20. The vertical model discretization was set to the default for each given combination of line length and electrode spacing. The starting value was set to “Auto”. The lateral and vertical constraints were set to the “Medium” settings....
Categories: Data
This data release has three components for each of the eight surveys that were conducted in 2018: 1) a geospatial dataset of the processed data; 2) tabular data of the processed waterborne resistivity profiling data and associated water-quality data; 3) tabular data of the raw waterborne resistivity data and associated water-quality data. In addition to the newly collected data from 2018, the waterborne resistivity data from 2016 (Miller and others, 2016) is included and has been re-processed to be consistent with the processing steps currently utilized and described herein. In fresh water aquifers, the geoelectric resistivity of earth materials commonly has a positive correlation with hydraulic conductivity (Faye...
Categories: Data;
Types: ArcGIS REST Map Service,
ArcGIS Service Definition,
Downloadable,
Map Service;
Tags: Apparent resistivity,
Arkansas,
Black River,
Cache River,
Continuous resistivity profiling,
This data release contains self-potential (SP) map data, two-dimensional electrical resistivity tomography (ERT) data, and time-lapse SP-monitoring data measured within the thermal springs discharge area of Hot Springs National Park in Hot Springs, Arkansas, in addition to the geospatial coordinates of each geophysical measurement and photographs of the reconnaissance and monitoring-survey layouts. Hot Springs National Park features 47 artesian thermal springs that discharge along the trace of a thrust fault at the base of Hot Springs Mountain. To better understand temporal aspects of thermal springs discharge at Hot Springs National Park, the U.S. Geological Survey, in collaboration with the U.S. National Park...
FDEM Processing The frequency domain electromagnetic (FDEM) data were downloaded from the GEM-2 instrument and aggregated into a single data file. The data were manually despiked and smoothed to remove negative values and the effects of metallic objects. A drift correction was applied by finding the average in-phase and average quadrature values for each frequency transmitted each time the base station was occupied. This average value was then used to calculate a linear trend of the data in time and the linear trend was subtracted from the data set. After the data were drift corrected, the data was leveled by calculating the arithmetic mean of the survey data subtracting that value from the dataset to level...
Categories: Data
The raw data files within the “Airborne electromagnetic, magnetic, and radiometric surveys of the Mississippi Alluvial Plain and Chicot Aquifer System, March 2018 and May - August 2021: Minimally Processed (Raw) Data” child item are broken up according to the three main objectives of these surveys: River surveys along the thalweg of major rivers within the MAP and the Chicot Aquifer extents; Levee surveys along the Mississippi and Arkansas rivers from Cairo, IL to Baton Rouge, LA and northwest from the confluence of the Mississippi and Arkansas rivers to Pine Bluff, AR; and gridded products mainly focused on gravel bars within the Mississippi River from Helena, MS to the confluence with the Arkansas River. The...
Categories: Data;
Tags: Arkansas,
Arkansas River,
Bayou Lacassine,
Bayou Teche,
Big Sunflower River,
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