Residents of the eastern part of Carroll County will see some low-flying aircraft in the coming weeks.
The flights are part of an effort to map geological resources, under the Earth Mapping Resource Initiative, also known as Earth MRI. The U.S. Geological Survey and the Arkansas Geological Survey are working together on the project.
From mid-October to December, planes will fly over a 15-county area in northern Arkansas. The planes will fly out of Branson, Mo., and the two planes used on the project will carry special equipment to measure variations in the earth’s magnetic field. Those variations are caused by different rock types, up to several miles below the surface.
Sensors will also assess soil and rock chemistry on the surface. A press release from the USGS notes that none of the instruments carried on the aircraft poses a health threat to humans or animals.
The Piper Navajo aircraft will be flown by pilots trained for low-level flight, altitudes from 250 to 1,000 feet, and will work a grid pattern. The grid will include passes at about 650 ft. apart on the north-south line, and the east-west flight lines will be almost a mile apart.
Data collected for this survey is part of a national-scale effort to acquire modern, high-resolution airborne and radiometric data. The survey will replace existing lower-quality geophysical data, collected mostly in the 1980s, that is of limited use for geological mapping. The new geophysical survey will use the latest technological developments that will allow the USGS to create high-resolution 3D representations of geology to depths several miles below the surface. This effort will show the distribution of groundwater and mineral and energy resources.
Data collected as part of the Arkansas survey will be made public and will be used by USGS and AGS to guide more detailed mapping.