Residents and visitors should not be alarmed to see a low-flying helicopter over Lemhi and Custer Counties west of Salmon, Idaho from September 6 to October 18, 2021. 

Map shows the airborne helicopter survey

Map shows the airborne helicopter survey west of nearby Salmon, just south of Montana-Idaho border (bold black line). Surveys will be conducted within/near the boundary margins (red polygon). Planned flight lines and survey information can be found online. (USGS map; Public domain.)

(Public domain.)

The U.S. Geological Survey and Idaho Geological Survey are co-leading the effort to conduct a helicopter-assisted airborne survey over approximately 1,160 square miles of the Salmon National Forest west of Salmon, Idaho. The instrumentation aboard the helicopter is passive, meaning it receives but does not emit signals for detection, and poses no health concerns or risks to humans, pets or wildlife. 

The survey aims to study cobalt and other important mineral resources concealed in ancient rock layers beneath the rugged landscape of north-central Idaho. Aerial coverage will extend north near the Idaho-Montana border and continue about 40 miles south through Lemhi and Custer Counties.  

The survey layout follows a grid pattern consisting of tightly spaced lines two to three miles apart. Flight elevations may vary from 300 to 1,000 feet above the ground as the helicopter attempts to maintain a constant flight height except when it encounters steep mountainous terrain. All survey flights will occur during visible daylight hours between 6am – 7pm MST. 

USGS and IGS scientists designed this helicopter-assisted survey to ensure they are able to safely and efficiently collect data over broad areas where accessibility by ground is slow or difficult. The helicopter is equipped with scientific instrumentation that measures Earth’s naturally occurring magnetic field, which will help scientists understand the geologic relationships associated with cobalt and other important mineral-bearing rock layers below Earth’s surface.  

The helicopter is operated by Sander Geophysics, out of Ontario, Canada. The company’s pilots are experienced and specially trained for low-level flying. Sander Geophysics is working with the Federal Aviation Administration to ensure the flights are in accordance with U.S. law governing airspace regulations. 


For more information, visit: USGS, IGS, USGS News Releases, 

USGS Contact Information: 
Geoffrey Phelps
Elizabeth Goldbaum
Release Date: 
September 9, 2021
Science Support: 
<em>Attribution: <a href="/mission-areas/energy-and-minerals">Energy and Minerals</a>, <a href="/energy-and-minerals/mineral-resources-program">Mineral Resources Program</a>, <a href="/unified-interior-regions/region-9">Region 9: Columbia-Pacific Northwest</a>, <a href="/unified-interior-regions/region-10">Region 10: California-Great Basin</a>, <a href="/centers/gmeg">Geology, Minerals, Energy, and Geophysics Science Center</a></em>
Contacts list: 
Contacts: <a href="/staff-profiles/geoffrey-phelps">Geoffrey Phelps</a>, <a href="/staff-profiles/elizabeth-goldbaum">Elizabeth Goldbaum</a>