The data collection will be conducted through the USGS Earth Mapping Resources Initiative (Earth MRI), a partnership between the USGS and state geological surveys that is revolutionizing our understanding of the nation’s geology and critical mineral resources which are vital to the U.S. economy, national security and clean energy technology.  

“These Earth MRI surveys represent a next-generation approach, bringing modern geophysics to bear that will allow us to fundamentally reevaluate our state’s inventory of resources,” said Mike Timmons, New Mexico Bureau of Geology and Mines director and state geologist of New Mexico. 

The survey’s focus will cover the North American Alkaline Igneous Belt, a geologic feature that stretches from the eastern edge of Alaska down through the Rocky Mountains and into Mexico. 

The unique alkaline igneous rocks in New Mexico’s portion of the belt contain deposits of gold, fluorine, zirconium, rare earth elements (REE), tellurium, gallium and other critical minerals and are commonly associated with ancient faults.

Tien Grauch, the lead USGS geophysicist for this survey, explained that the new high-resolution geophysical survey has the potential to reveal even deeper layers of igneous rocks and faults than what’s known. 

“Combined with geologic mapping that is ongoing by the New Mexico Bureau of Geology, the new information may lead to a better understanding of critical mineral resources in the region,” said Grauch. 

The survey footprint was designed in close collaboration with the New Mexico Bureau of Geology and Mineral Resources (NMBGMR), where officials say the geophysical data will improve their understanding of their state’s potential economic and natural resources. 

While the primary benefit of this survey is to see into the region’s subsurface and map critical minerals, the data will also allow geoscientists to better understand the region’s groundwater flow, which supports NMBGMR’s Aquifer Mapping Program. 

“This will be our first high-definition look at this area’s geology, and we can leverage the data across so many disciplines,” said Virginia McLemore, NMBGMR principal senior economic geologist. “Every opportunity we get to bring in new tools or data, we learn something completely new.” 

These Earth MRI airborne geophysical surveys will collect a combination of magnetic and radiometric data. These data can be used to map rocks from just beneath vegetation and shallow sediment cover down to several miles underground. Magnetic data can be used to identify inactive faults, lava flows, other geologic features and potentially the signatures of mineral deposits. Radiometric data indicate the relative amounts of potassium, uranium and thorium in shallow rocks and soil. 

Scientists use this information to help map rocks that may contain mineral deposits, faults that may rupture during an earthquake, areas that may be prone to increased radon, and geologic features that affect groundwater or energy resources.

This New Mexico survey complements a similar Earth MRI geophysical survey that will be flown over the alkaline igneous belt in Texas later in the year. Both these surveys adjoin an Earth MRI survey in the Trans-Pecos region that has already been completed.

The initial airborne geophysical survey may be followed by additional investments, including new geologic maps, geochemical sampling, and other techniques to better understand the region’s geologic framework.

Since 2021, the Bipartisan Infrastructure Law has advanced scientific innovation through a \$320 million investment for the USGS to better map the Nation’s mineral resources, both still in the ground and in mine wastes, and to preserve historical geologic data and samples. Through the end of fiscal year 2024, more than \$160 million has been obligated for Earth MRI initiatives, propelling efforts to make “once-in-a-generation” advancements in the nation’s geologic and geophysical data collections and mapping.