See more from this Division: Topical Sessions
See more from this Session: Fault Seals or Conduits? Insights from Hydrologic and Petroleum Systems
Abstract:
While it is probable that the elevated salinities near the BR fault reflect salt dissolution, a more likely source of the saline contamination lies to the south, where dissolution of salt domes has produced saline plumes which extend upward all the way to the ground surface. Conduits for upward transport of brine appear to be faults associated with the domes rather than regional listric faults. A detailed study has been done of the spatial variations in salinity calculated from logs for wells on either side of the BR fault. Most of the logs were run in the 1960s, so the log information provides a snapshot in time of the salinity structure prior to significant groundwater contamination. The spatial variations in salinity across the fault are consistent with natural lateral interfingering of freshwaters derived from the north and brackish waters from the south. A 2004-2005 study of chloride concentrations in the ground water showed that the highest chloride concentrations occur at mid-depth in the aquifer system rather than the base, as might be expected if salt transport were up the fault.
See more from this Division: Topical Sessions
See more from this Session: Fault Seals or Conduits? Insights from Hydrologic and Petroleum Systems