Supporting information and data for "Chapter 1: Constraining Hydraulic Permeability at Great Depth by Using Magnetotellurics" in Pepin JD (2019) New Approaches to Geothermal Resource Exploration and Characterization (PhD dissertation)

This supporting information includes additional text, figures, and tables regarding the newly derived sodium-chloride fluid resistivity model and the magnetotelluric (MT) inversion methodology. It also includes additional simulated electrical resistivity results that are not explicitly presented in the main text; the three simulations featured in the main text are selected to represent this larger set of simulations.

Six supporting datasets are also described in this document. The first is a compilation of previously published laboratory-measured electrical resistivity data taken at various temperatures and salinities for sodium-chloride fluids. While all of this data is considered reliable, the measurement accuracy is variable, since the data were compiled from work that was published over a time period ranging from 1907 to 2009. These data are used to derive a thin-plate spline model that permits estimation of sodium-chloride fluid resistivity over an extensive range of salinities (6 to 321,420 mg/L) and temperatures (0 to 309°C). A table of fluid resistivity, as estimated by the spline model, that covers salinities from 0.001 to 5.5 mol/L over a temperature range of 0 to 300°C is also provided. A zip folder containing an R script and the necessary input files to use this spline model independently is included as well. Tables containing the hydrologic modeling results are provided for the three simulations featured in the main text. Lastly, the MT forward responses and calculated inversion fits to those responses are enclosed. The forward responses include both noise-free MT curves and those with 2% Gaussian noise added; the noisy curves were used exclusively for the inverse analysis.