Geophysical Assessment of Karst Activity

UTC R189 Disclaimer The contents of this report reflect the views of the author(s), who are responsible for the facts and the accuracy of information presented herein. This document is disseminated under the sponsorship of 16. Abstract MST proposes to acquire electrical resistivity data within a pipeline/roadway ROW. These geophysical data will be processed, analyzed and interpreted with the objective of locating and mapping any subsurface voids that might compromise the integrity of the pipeline/roadway. The main project deliverable will be a map showing the location and estimated depth of any voids. EXECUTIVE SUMMARY A geophysical data set consisting of ten electrical resistivity profiles and two MASW (acronym for multichannel analyses of surface waves) profiles were acquired along traverses in immediate proximity to two active sinkholes at the study site. Analysis of the acquired geophysical data supports the conclusion that that none of the ten traverses (with the possible exception of traverse 5) overlies air-filled subsurface voids of any significant size. The data also support the conclusion that sinkholes #1 and #3 developed along or adjacent to N/S-trending solution-widened joints/fractures which do not appear to extend beneath the traverses closest to the buried utility of interest.