USU geochemist studies Alaska’s Denali fault – Cache Valley Daily

USU geochemist Dennis Newell collects a sample from a spring along a remote segment of Alaska’s Denali Fault. He reports evidence of mantle-to-crust connections that increase the possibility of a future major earthquake. (Photo Credit: Jeff Benowitz)

LOGAN – Utah State University professor Dennis Newell is a geochemist who was joined by three colleagues last summer searching Alaska’s interior to gather data from springs along a segment of Alaska’s Denali Fault.

They collected and analyzed helium and carbon isotope data from those springs, along the fault, seeking to understand the fault’s seismic cycle. Their results are featured in a recent issue of the journal Geology.

“Of course, we don’t know how to predict earthquakes, and so lots of research is conducted to understand what is that cycle between the building up of energy or strain, and then if it gets released in an earthquake,” says Newell. “And how do those faults interact with groundwater flows in those regions?”

Newell and his team reported evidence of connections between the upper crust of the earth and the underlying mantle, which increases the possibility of a future major earthquake.

“We know that the mantle, with depths of greater than 40 or 100 kilometers below your surface in these areas, will have a certain ratio of gasses,” Newell adds. “And comparing that to the upper crust of the atmosphere, we can basically quantify how much helium is there from the mantle.”

Newell said crust-to-mantle connections along major faults are critical for understanding linkages between deep fluid flow and fault healing.

Newell’s colleagues were Jeff Benowitz, Alaska-based geochronologist, Sean Regan of the University of Alaska-Fairbanks and USU doctoral candidate Coleman Hiett.