Later this week, a helicopter equipped with a pointy red “stinger” will appear over the La Plata Mountains – but no, the region is not under attack.
A helicopter carrying specialized equipment to gather geophysical data will be making low-elevation passes throughout Southwest Colorado beginning Wednesday.
The project, dubbed “Earth Mapping Resources Initiative,” is being conducted by the U.S. Geological Survey at the request of Congress. The data collected will allow geophysicists to create highly detailed three-dimensional maps of the region’s underlying geology, which can be used by mining companies in search of critical minerals and to better understand the geologic history of the region.
“Congress wanted us to do this is to promote exploration by the private sector,” said Tien Grauch, the lead USGS geophysicist on the project. “There is a lot more to it, though, because basic geologic information informs an awful lot of different applications.”
The data will also help geologists understand groundwater pathways, including the hydrological connections to contaminated historic mines. It will also yield a better understanding of the Colorado mineral belt – the ore-rich strip of land stretching from the toe of the San Juan Mountains up to Boulder – and a better understanding of naturally occurring radon.
The USGS contracted with NV5 Geospatial, out of Florida, which hired Canada-based Precision GeoSurveys to gather the data and EDCON-PRJ out of Denver to process it.
The helicopter, piloted by Harmen Keyser, carries two instruments to record data.
A long “stinger” protrudes from the front of the aircraft carrying a magnetometer. The device measures changes in the earth’s magnetic field.
Inside the helicopter, a 250-pound box contains a gamma ray spectrometer that measures the energy released by decaying radioactive elements.
Although the technology is passive – it does not collect imagery and will not affect anyone in the mapping area – residents and recreationalists may notice the helicopter flying approximately 330 feet overhead.
The aircraft will fly in lines 660 feet apart at speeds between 70 and 90 mph. It will climb to 1,000 feet over populated areas.
The survey area includes two swaths of land, one in the southwest and another near Buena Vista. Surveys will begin near Durango on Thursday and continue until snowfall makes data collection impossible. The flights will continue once the snow melts next summer.
The flight paths are planned to avoid wilderness areas where speculation would not be possible.
Grauch warns that although the USGS’ mandate is to map the geology in search of critical minerals, it does not necessarily mean another mining boom is on the horizon.
“Congress wanted to have us do this to promote the mining companies’ interest in various areas,” she said. “It doesn’t mean that they’re going to be interested because they’re driven by economics.”
rschafir@durangoherald.com
