Subduction Zones

Vertical Motions offshore Costa Rica

To get at the upper plate's motions, I've been utilizing a technique called seismic sequence stratigraphy within the 3D volume of seismic reflection data. There are a bunch of different flavors to this technique out there, and researchers (and oil companies) really dive into the weeds on this, but essentially the tool is utilized to subdivide offshore strata (layers of sediments) into time.

Mapping unconformities throughout the 3d volume results in unconformable horizons with really neat detail. Check this one out. It's labelled L1 in the above figure and is ~2.5 m.y. See the channel systems to the left? And the big folds to the right? Pretty cool.

Link to paper: pubs.geoscienceworld.org/gsa/geosphere/article/528574/pleistocene-vertical-motions-of-the-costa-rican

Shallow megathrust morphology

​I've looked at a lot of slicks along onshore faults and it seems like we've stumbled onto them along offshore mega-faults. It turns out the shallow megathrust is corrugated. Spectacular.

Link to paper: www.nature.com/articles/s41561-018-0061-4

Press: www.usgs.gov/center-news/giant-grooves-discovered-earthquake-fault-offshore-costa-rica
Press: news.ucsc.edu/2018/02/megathrust-imaging.html

Geothermal

Structural Controls of the Neal Hot Springs Geothermal System, Malheur County, OR

I spent some time mapping the detailed geology surrounding  Neal Hot Springs and its geothermal system and came up with a left-stepping, west-dipping normal-oblique-slip fault system. Along with decent rock exposure, we had an abundance of well and geophysical data, thanks to collaborations with US Geothermal Inc and Boise State.

Link to thesis: edwards_joel_h_201305_ms.pdf
Link to geologic map: neal_hot_springs_geologic_map_edwards_etal.pdf

Favorable structural settings for geothermal, Basin and Range

Jim Faulds and company came up with a handful of structural settings that seem to be associated with known geothermal systems in the Basin and Range.

Link to paper: www.atlasgeoinc.com/wp-content/uploads/Faulds_etal_Structural_Settings_GRC_2011.pdf