Michael A. Mitchell

United States Geological Survey | USGS · California Volcano Observatory

In underground mining, water inflow poses a serious danger that can result in loss of life and the destruction of infrastructure. In some situations, flooded mines have to be abandoned entirely. The DC resistivity field data used in this study comes from a potash mine in Saskatchewan which has been battling water inflow problems for over three deca...

Developments in multi-channel instrumentation systems and computational resources have made the collection of large, non-conventional DC resistivity datasets commonplace. Although these large datasets can greatly improve the resolution of recovered inverse models, they present challenges for standard data quality control (QC) methodologies. These l...

With developments in instrumentation and computational resources, the collection of large, non-conventional DC resistivity datasets has become commonplace. While the increased data content of these large datasets can significantly improve the resolution of inverse models, these datasets also present challenges for standard data quality control (QC)...

The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three posters. In the first...

The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three papers. In the first,...

We use P wave and S wave arrivals from microseismic earthquakes to construct 3-D tomographic Vp and Vs images of the magma storage region beneath Askja's central volcano in the Northern Volcanic Zone of Iceland. A distinctive ellipsoidal low-velocity anomaly, with both Vp and Vsvelocities 8-12% below the background, is imaged at 6-11 km depth benea...

In conjunction with the National Forest Service, a number of different geophysical datasets were collected over the region adjoining the southwest end of the Great House at Chimney Rock, Colorado. The investigations aim to determine if the foundations for more rooms exist in this region, as early archeological sketches indicate. The following types...

We integrate seismic and magnetic data to characterize the Tacoma fault and northern portions of the Tacoma Basin in western Washington State. The Tacoma basin, a deep (greater than 4 km) basin filled with Eocene and younger sediments, is a major physiographic feature underlying southern Puget Sound. Its northern margin is bounded by the Tacoma fau...