Compaction of Subsurface Sediments in the Chicot and Evangeline Aquifers in the Houston-Galveston Region, Texas

The U.S. Geological Survey in cooperation with the Harris‐Galveston Subsidence District, City of Houston, Fort Bend Subsidence District, and Lone Star Groundwater Conservation District has produced this dataset of compaction values in the Chicot and Evangeline aquifers in the Houston‐Galveston region, Texas. This dataset shows compaction values of subsurface sediments (mostly in the fine-grained silt and clay layers because little compaction occurs in sand layers) in the Chicot and Evangeline aquifers was recorded continuously by using analog technology at the 13 extensometers at 11 sites that were either activated or installed between 1973 and 1980. The cumulative compaction data for each extensometer are collected about 13 times per year during site visits. The amount of cumulative compaction for each site visit is determined by subtracting the previously recorded compaction value from the ending compaction value. This data release will be updated annually with new compaction data recorded from the previous year.