Self-potential, electrical resistivity tomography, and water temperature and electrical conductivity data pertaining to the sources of groundwater at Krause Springs, Spicewood, Texas, February 4–15, 2019

This data release contains self-potential (SP), electrical resistivity tomography (ERT), and water temperature and conductivity data measured during a geophysical survey at the Krause Springs property in Spicewood, Texas. The geophysical survey was completed February 4–15, 2019, over approximately 3.1 acres on the western side of the property adjacent to the main visitor parking lot and entrance facilities. SP data were measured on the land surface within the survey area to locate SP anomalies attributed to groundwater flow. The locations and spatial distribution of the discovered SP anomalies were used to orient four ERT profiles to intersect the SP anomalies. Two ERT profiles, consisting of 84 stainless steel electrodes separated by 2 m, were oriented approximately in a south-to-north (S–N) alignment. The other two ERT profiles, which consisted of 84 stainless steel electrodes separated by 1 m, were oriented in an east-to-west (E–W) alignment and approximately perpendicular to the two S–N oriented profiles. The resistance data measured at the ERT profiles were used to produced high-resolution images of the subsurface resistivity distribution beneath each profile to a maximum depth of 35 m for the S–N oriented profiles and 17 m for the E–W oriented profiles. The resulting datasets contained in this data release include: (1) 386 SP measurements acquired along seventeen linear profiles using a voltmeter and two non-polarizing copper-sulfate electrodes, (2) 13,605 electrical resistance measurements collected along four ERT profiles (3,442 measurements on ERT1, 3,422 measurements on ERT2, 3,274 measurements on ERT3, and 3,467 measurements on ERT4) with an IRIS Syscal Pro Switch 96 resistivity meter by using reciprocal Schlumberger electrode configurations, (3) formatted input and parameter-values files for inversion of the ERT resistance measurements, (4) a file containing the inverse-modeled two-dimensional electrical resistivity distributions beneath each ERT profile, (5) water temperature and electrical conductivity and resistivity measurements acquired with a handheld conductivity meter at 11 different locations around the Krause Springs property where spring-flow discharged during the geophysical survey, and (6) a State of Texas well report and driller’s log corresponding to a monitoring well that was drilled into coincident SP and ERT anomalies. Additionally, the data sets include global positioning system (GPS) coordinates of the SP, ERT, and water temperature and electrical conductivity measurement locations.