Media Alert: Low-Level Airplane Flights to Image Geology Over Parts of Southeastern Arizona

USGS Low-level Airplane Surveys Begin mid-October

By Bipartisan Infrastructure Law Investments September 29, 2023

Editor: In the public interest and in accordance with Federal Aviation Administration regulations, the USGS is announcing this low-level airborne project. Your assistance in informing the local communities is appreciated.

RESTON, Va. — Low-level airplane flights are planned over a broad region in southeastern Arizona to image geology using airborne geophysical technology. The survey will be conducted from mid-October for approximately 7 months, weather and wildfire restrictions permitting.

Flights will cover an area of more than 10,880 square miles (28,180 square kilometers) and will include areas within Cochise, Graham, Greenlee, Pima, Pinal and Santa Cruz counties in Arizona and Catron (aircraft turnaround only), Grant and Hidalgo counties in New Mexico.

Image shows a road map of southeastern Arizona with the survey area marked in a red polygon — *A map of the Arizona Earth MRI Airborne Geophysical Survey.*

The flights will be based out of Cochise County Airport in Willcox, Arizona. The flights could shift with little warning to other parts of the survey area as necessitated by adverse flying conditions.

The purpose of the survey is to provide images that expand the fundamental knowledge of geology underpinning the Arizona copper porphyry belt in southeast Arizona near the New Mexico border. The Arizona copper porphyry belt includes some of the world’s largest endowments of mineral resources like copper and molybdenum. The new, high-resolution data will help define some potential concealed mineral resources and complement geological and geochemical surveying efforts that the Arizona Geological Survey is undertaking.

The new geophysical data will be processed to develop high-resolution three-dimensional representations of bedrock composition and structure to depths more than 3,280 feet (1 kilometer) below the surface.

The 3D models and maps are important for improving our understanding of critical mineral resource potential, water resources, groundwater pathways near legacy mining areas, parameters for infrastructure and land use planning, and potential risks of naturally occurring radon.

The airplane will fly along pre-planned fight paths relatively low to the ground at about 400 feet (120 meters) above the surface. The ground clearance will be increased to 1,000 feet (300+ meters) over populated areas and will comply with Federal Aviation Administration (FAA) regulations. Flights will follow north-south lines spaced about 650 feet (200 meters) apart and east-west lines about 3,280 feet (1 km) apart.

Image: Low-Flying Airplane Maps New Madrid Zone — An example of the kind of aircraft that will perform the survey. The magnetic sensor (magnetometer) is located at the tip of the "stinger" attached to the rear of the airplane. The survey is designed to measure the magnetic field of the earth, which is related to rock formations that lie below the land surface. Image courtesy of EDCON-PRJ, Inc.

The USGS is contracting with NV5 GeoSpatial, Inc. in partnership with EDCON-PRJ, Inc. to collect data.

The survey will use a fixed-wing single-engine Cessna TU206G equipped with an elongated “stinger” mounted to the underside of the cabin extending behind the airplane. Instruments in the stinger and inside the cabin will measure variations in the Earth’s magnetic field and natural low-level gamma energy created by different rock types.

The scientific instruments on the airplane are completely passive with no emissions that pose a risk to humans, animals, or plant life. No photography or video data will be collected. The data collected will be made freely available to the public once complete. The aircraft will be flown by experienced pilots who are specially trained and approved for low-level flying. The company works with the FAA to ensure flights are safe and in accordance with U.S. law. The surveys will be conducted during daylight hours only.

The survey fits into a broader effort by the USGS, the AZGS and many other state geological surveys and other partners, including private companies, academics and State and Federal agencies to modernize our understanding of the Nations’ fundamental geologic framework and knowledge of mineral resources. This effort is known as the Earth Mapping Resources Initiative, and it includes airborne geophysical surveys like this one, geochemical reconnaissance surveys, topographic mapping using LiDAR technology, hyperspectral surveys, and geologic mapping projects.

More information can be found here. To learn more about how the USGS is investing the resources from the Bipartisan Infrastructure Law, visit our website. To learn more about USGS mineral-resource and commodity information, please visit our website and follow us on Twitter.