Thermal Processes, Heat Flow, Tectonics

The thermal studies group has several active research projects centered on the theme of temperatures in the Earth’s crust, heat flow, and geologic and hydrologic processes that affect temperatures.

1. Regional heat flow studies related to continental deformation.  We are using Earthscope strainmeter sites to determine heat flow values and will integrate the heat flow studies with other Earthscope findings on plate movements and intra-plate deformation. (Collaboration with Rob Harris at Oregon State University)

2.  Geothermics of climate change.  This long-term project evaluates how borehole temperature profiles can best be used to reconstruct past changes of temperature on the Earth’s surface.  This study is an important component of global warming studies.

3.  A geothermal-climate change observatory.  We have been running an observatory EPO (Emigrant Pass Observatory) for more than a decade.  A weather station mounted next to a borehole permits us to study how meteorologic variables affect ground temeprature and eventually the deep rock temperature.

4. Precision gravity and groundwater.  We have several experiments in progress in which repeat gravity surveys are used to monitor ground water injection (water storage) or extraction (geothermal fluids).

5. Thermal isostasy.  Continental elevation can be used as a measure of the thermal state of the lithosphere.  But the application is not straight forward; our lab is working out the details.

Roy, S, R.N. Harris, R.U.M. Rao, and D.S. Chapman, Climate Change in India Inferred From Geothermal Observations, J. Geophys. Res., 10.1029/2001JB000536, 2002

Gettings, P., R.N. Harris, R.G. Allis, and D.S. Chapman, Gravity signals at The Geysers geothermal system,  Proceedings of the 27th Workshop on Geothermal Reservoir Engineering, Stanford University, Stanford, CA, Jan. 28-30, 8 pp., 2002.

Armstrong, P.A., T.A. Ehlers, D.S. Chapman, K.A. Farley, and P.J.J. Kamp, Exhumation of the Central Wasatch Mountains, Utah: 1. Patterns and timing of exhumation deduced from low-temperature thermochronology data, J. Geophys. Res., v. 108, no. B3, 2172, doi: 10.1029/2001JB001708, 2003.

Ehlers, T.A., S. D. Willett, P.A. Armstrong, and D.S. Chapman, Exhumation of the Central Wasatch Mountains, Utah: 2. Thermokinematic model of exhumation, erosion,  and thermochronomoter interpretation, J. Geophys. Res., v. 108, no. B3, 2173, doi: 10.1029/2001JB001723, 2003.

Harris, R. N., A. T. Fisher, and D. S. Chapman, Fluid flow through seamounts and implications for global mass fluxes, Geology, 32, 725-728, 2004.

Harris, R. N., and D. S. Chapman, Deep-seated oceanic heat flow, heat deficits, and hydrothermal circulation, in Hydrogeology of the Oceanic Lithosphere, E. Davis and H. Elderfield, Editors, Cambridge University Press, Cambridge, 311-336, 2004.

Bartlett, M, D. S. Chapman, and R.N. Harris, Snow and the ground temperature record of climate change, Journal of Geophysical Research - Earth Surface, 109, F04008, doi:10.1029/2004JF000224, 2004.

Bartlett, M. G., D.S. Chapman, and R.N. Harris, Snow effect on North American ground temperatures, 1950-2002, J. Geophys. Res., 110, F03008, doi: 10.1029/2005JF000293, 2005.

Harris, R.N., and D.S. Chapman, Borehole temperatures and tree rings:  seasonality and estimates of extratropical Northern Hemisphere warming, J. Geophys. Res., 110, F04003, doi: 10.1029/2005JF000303, 2005.

Bartlett, M.G., D.S. Chapman, and R.N. Harris, A decade of ground-air temperature tracking at Emigrant Pass Observatory, Utah, J. Climate, 19, no. 15, 3722-3731, 2006.

Hasterok, D., and D.S. Chapman, Continental thermal isostasy I: methods and sensitivity, J. Geophys. Res. (in review, July, 2006).

Hasterok, D., and D.S. Chapman, Continental thermal isostasy II:  application to North America, J. Geophys. Res. (in review, July, 2006).