AEM processed survey data of the Mississippi Alluvial Plain, November 2018 - February 2019
공공데이터포털
Airborne electromagnetic (AEM), magnetic, and radiometric data were acquired November 2018 to February 2019 along 16,816 line-kilometers (line-km) over the Mississippi Alluvial Plain (MAP). Data were acquired by CGG Canada Services, Ltd. with three different helicopter-borne sensors: the CGG Canada Services, Ltd. Resolve frequency-domain AEM instrument that is used to map subsurface geologic structure at depths up to 100 meters, depending on the subsurface resistivity; a Scintrex CS-3 cesium vapor magnetometer that detects changes in deep (hundreds of meters to kilometers) geologic structure based on variations in the magnetic properties of different formations; and a Radiation Solutions RS-500 spectrometer that detects the abundance of natural radioelements potassium, uranium, and thorium in the upper 20-30 cm that is used to determine differences in soil constituents. The survey was flown at a nominal sensor flight height of 30 m above terrain with 6- to 12-kilometer spaced east-west flight lines. The main survey block covers 13,641 line-km, including two north-south tie lines extending the length of the survey. Several rivers were surveyed along their center axes, covering 2,640 line-km (flight line numbers 8010000-8100001 nonsuccessive), and two separate inset grids were flown: (1) Crowley's Ridge in Arkansas with 1.5-km spaced east-west flights for a total of 406 line-km (flight line numbers 24025-24477 nonsuccessive) and (2) University of Memphis focus area in Tennessee with variable line spacing for a total of 129 line-km (flight line numbers 30010-30060 and 39010-39050 nonsuccessive). This data release includes the averaged and culled AEM data along all flight lines that were used to produce the final resistivity models (https://www.sciencebase.gov/catalog/item/5d76ba5ce4b0c4f70d01ff94). Digital data of the processed soundings are provided and fields are defined in the data dictionary (https://www.sciencebase.gov/catalog/item/5d76bac9e4b0c4f70d01ff9d).
Airborne electromagnetic, magnetic, and radiometric survey of the Mississippi Alluvial Plain, Mississippi Embayment, and Gulf Coastal Plain, September 2021 - January 2022
공공데이터포털
Airborne electromagnetic (AEM), magnetic, and radiometric data were acquired September 2021 to January 2022 along 27,204 line-kilometers (line-km) over the Mississippi Alluvial Plain (MAP), Mississippi Embayment, and Gulf Coastal Plain. Data were acquired by Xcalibur Multiphysics (Canada), Ltd. with three different airborne sensors: the 30Hz TEMPEST time-domain AEM instrument that is used to map subsurface geologic structure at depths up to 300 meters (m) depending on the subsurface resistivity; a Scintrex CS-3 cesium vapor magnetometer that detects changes in deep (hundreds of meters to kilometers) geologic structure based on variations in the magnetic properties of different formations; and a Radiation Solutions RS-500 spectrometer that detects the abundance of natural radioelements potassium, uranium, and thorium in the upper 20-30 centimeters that is used to determine differences in soil constituents. The survey was flown at a nominal sensor flight height of 120 m above terrain with 300 and 600 km (nominal) spaced east-west flight lines. The main survey block covers 24,654 line-km. The Chicot aquifer focus area was surveyed along 360 line-km (flight numbers 2900101-2900421 nonsuccessive). The Mississippi River and the Atchafalaya River were surveyed along their center axes, covering 742 line-km (flight line numbers 6004001-6004003 and 5002001-5002002). Two separate inset grids were flown: (1) University of Memphis (UMemphis) focus area lines with 500 m line spacing for a total of 1260 line-km (flight line numbers 1000301-1030001 nonsuccessive), and (2) Hot Springs focus area with 350 m line spacing for a total of 188 line-km (flight line numbers 2001001-2027001 nonsuccessive). 91-series lines are repeat test-lines flown periodically throughout the survey, with one repeat line established for each base station. 901- and 904-series lines are flown under standard survey conditions with the transmitter on and the receiver off to evaluate the noise contribution from the acquisition system pre- and post- flight, respectively. 902- and 905-series lines are ~60 second high-altitude datasets collected to evaluate the system out of ground-response pre- and post- flight, respectively. 903-series lines are 30-40 second 'swoop' datasets to confirm correct operation of the system during variable pitch manoeuvres. 906-series lines are flown under standard survey conditions with the transmitter off and the receiver on to evaluate the ambient noise in the system. AEM data were inverted using 1-D inversion to produce models of electrical resistivity along flight paths.
Airborne electromagnetic, magnetic, and radiometric survey of the Mississippi Alluvial Plain, November 2019 - March 2020: AEM processed survey data
공공데이터포털
Airborne electromagnetic (AEM), magnetic, and radiometric data were acquired November 2019 to March 2020 along 24,030 line-kilometers (line-km) over the Mississippi Alluvial Plain (MAP). Data were acquired by CGG Canada Services, Ltd. with three different airborne sensors: the CGG Canada Services, Ltd. TEMPEST time-domain AEM instrument that is used to map subsurface geologic structure at depths up to 300 meters (m), depending on the subsurface resistivity; a Scintrex CS-3 cesium vapor magnetometer that detects changes in deep (hundreds of meters to kilometers) geologic structure based on variations in the magnetic properties of different formations; and a Radiation Solutions RS-500 spectrometer that detects the abundance of natural radioelements potassium, uranium, and thorium in the upper 20-30 centimeters that is used to determine differences in soil constituents. The survey was flown at a nominal sensor flight height of 120 m above terrain with 6-kilometer spaced east-west flight lines. The main survey block covers 22,250 line-km. The Mississippi River and the Arkansas River were surveyed along their center axes, covering 1,225 line-km (flight line numbers 500101 and 700201-700206 nonsuccessive), and three separate inset grids were flown: (1) Ozark basement reconnaissance lines with variable line spacing for a total of 234 line-km (flight line numbers 400801-401401 nonsuccessive), (2) Shellmound focus area in Mississippi with 250 m line spacing for a total of 485 line-km (flight line numbers 604501-608101 nonsuccessive), and (3) New Madrid Seismic Zone focus area in Missouri and Tennessee with variable line spacing for a total of 161 line-km (flight line numbers 710101-710401 nonsuccessive). 91-series lines are repeat test-lines flown periodically throughout the survey, with one repeat line established for each base station. 902- and 905-series lines are ~60 second high-altitude datasets collected pre- and post- flight, respectively, to evaluate the system out of ground-response. This data release includes minimally processed (raw) AEM data as supplied by CGG Canada Services, Ltd. (https://www.sciencebase.gov/catalog/item/5f4e951882ce4c3d1233cb7d), the fully processed (downsampled by averaging) sounding data (https://www.sciencebase.gov/catalog/item/5f4e953482ce4c3d1233cb82), and inverted resistivity depth sections along all flight lines (https://www.sciencebase.gov/catalog/item/5f4e954682ce4c3d1233cb84), as well as unprocessed and processed (following International Atomic Energy Agency Technical Report procedures) radiometric data as supplied by CGG Canada Services, Ltd. (https://www.sciencebase.gov/catalog/item/5f4e951882ce4c3d1233cb7d). Data acquisition and minimal processing was conducted by CGG Canada Services, Ltd. and described in detail in the contractor's report. Digital data from production flights are provided in ASEG-GDF2 format, an ASCII format geophysical data standard that uses a self-describing collection of files to allow data to be automatically identified and read by a computer application. Data fields in the data file (.DAT) are defined in the associated definition file (.DFN). Please see the ReadME included in this data release for a description of how to interpret the .DFN files or visit https://www.aseg.org.au/sites/default/files/pdf/ASEG-GDF2-REV4.pdf for more information on the ASEG-GDF2 standard.