Airborne electromagnetic, magnetic, and radiometric survey of the Mississippi Alluvial Plain, March 2018 and May - August 2021

Airborne electromagnetic (AEM), magnetic, and radiometric data were acquired May 25 through August 7, 2021, along 10,706 line-kilometers (line-km) over the Mississippi Alluvial Plain (MAP) and the Chicot Aquifer extent   in the southeastern United States. These helicopter-based surveys collected data with a frequency-domain AEM system (Xcalibur Multiphysics RESOLVE), a cesium vapor magnetometer (Scintrex CS-3), and radiometric spectrometer (Radiation Solutions RS-500) at altitude of 30 meters (m) above the land surface. These sensors imaged a series of rivers and levees throughout these two areas focusing on water resources and infrastructure assessment.
This data release includes minimally processed (raw) data, as supplied by the airborne survey contractor (Xcalibur Multiphysics), for all three sensors along all flight lines. Additionally, the AEM survey files contain the fully processed data (all corrections applied and any anomalies removed, but before any modeling), and inverted resistivity models (final modeled data) along all flight lines. 
Data files contained in this data release include:
Contractor's report- Description of data acquisition and minimal processing as conducted by Xcalibur Multiphysics (Airborne Survey Contractor). 
Data were collected on the following 16 rivers:
Rivers within the MAP boundary:  Black, White, Big Sunflower, Little Sunflower, Ouachita, Tensas, Obion, Saline, Little Red, and Bogue Phalia.
Rivers within the Chicot Aquifer extent  :  Mermentau, Calcasieu, Sabine, Vermillion, Bayou Teche and Bayou Lacassine.
Select levee reaches were surveyed along the Mississippi and Arkansas Rivers.  Where possible, lines were flown along the toe of the levee both on the side adjacent to the river and on the side opposite the river.  In addition, where possible, a third line was flown 91m (300 feet) offset from the toe of the levee opposite to the river. Additional processing was done on all levee lines and is described in the data dictionaries and processing step sections of the metadata included in the “Processed Data” and “Resistivity Models” child items of this data release.
Seven gridded surveys   were collected also:
Four grids at different resolutions were collected over gravel bars within   the Mississippi River
250 m Line Spacing
Prairie Point
Island 63
Crumrod
100 m Line Spacing
White River
23 line-km at a 100 m line spacing over a property   near Minter City, Mississippi (referred to as the Melton grid).
268 line-km at a 500 m spacing over a series of the drill core locations near Paragould, AR. Referred to in this release as the AR OSL grid.
100 line-km at variable spacings over Raccourci Old River, a relic oxbow near Batchelor, LA.  Referred to in this release as the Raccourci grid.
A dataset collected on small levees near Greenville, Mississippi, in March 2018 is also included in this data release.  The survey includes four lines parallel to and over the levee for a total of 27 line-km. This dataset was collected as an evaluation of the technical approach used on the more comprehensive surveys in the MAP and Chicot Aquifer extents. This dataset contains AEM data only (magnetic and radiometric data   were not collected). 
Additional detail on flight line numbers and citations for the various methods used in the collection and processing of the radiometric data is included in the supplemental section.

Tags: aeromagnetic-surveying, aeroradiometric-surveying, arkansas, arkansas-river, bayou-lacassine, bayou-teche, big-sunflower-river, black-river, bogue-phalia, calcasieu-river, chicot-aquifer, electromagnetic-surveying, electromagnetics, engineering-sciences, environment, geology-geophysics-and-geochemistry-science-center, geophysics, geoscientificinformation, geospatial-datasets, gggsc, groundwater, hydrogeology, illinois, little-red-river, little-sunflower-river, louisiana, magnetic-field, magnetics, mermentau-river, mississippi, mississippi-alluvial-plain, mississippi-river, mississippi-river-valley-alluvial-aquifer, missouri, mrva, obion-river, ouachita-river, raccourci-old-river, radiometrics, resistivity, sabine-river, saline-river, tennessee, tensas-river, usgs-62069b13d34ec05caca511f0, vermillion-river, water-availability-and-use-science-program, water-resources, wausp, white-river
Organization: Department of the Interior