All water that exists beneath the land surface, but more commonly applied to water in fully saturated soils and geologic formations.
Availability of groundwater data for California, water year 2010 [ More info] Map of California showing the number of wells (by county) with available water-level or water-quality data for Water Year 2010, with descriptions of the data and instructions for obtaining them.
BRASS: Bedrock Regional Aquifer Systematics Study [ More info] Description of the project to publish new bedrock geologic maps in the United States to advance the understanding of the region's bedrock aquifers. Includes list of projects.
Bemidji Project crude-oil research project: background information [ More info] The study of petroleum in both the saturated and unsaturated zones, to better understand the processes that control contaminant behavior, and to use this understanding to estimate the future behavior of the contaminants.
Borehole geophysics as applied to geohydrology [ More info] Project summary, photos of logging truck, and bibliographies on log interpretation techniques and instrumentation to record geophysical data in wells and test holes for studying ground water hydraulics and evaluate waste disposal sites.
California's Central Valley Groundwater Study: A Powerful New Tool to Assess Water Resources in California's Central Valley [ More info] Modeling effort that integrates a wide variety of geographic, hydrologic, agricultural, climatic, and biological information to help local land managers address resource use issues.
Changes in Water Levels and Storage in the High Plains Aquifer, Predevelopment to 2007 [ More info] Summarizes changes in water levels and drainable water in storage in the High Plains aquifer from predevelopment (before about 1950) to 2007.
Changes in water levels and storage in the High Plains Aquifer, predevelopment to 2009 [ More info] Summarizes graphically the areas where water levels have dropped, and by how much, in this extensive underground water reservoir that covers several states in the mid-continent.
Detection and measurement of land subsidence using Global Positioning System surveying and interferometric synthetic aperture radar, Coachella Valley, California, 1996-2005 [ More info] Detailed measurements of elevation help to understand the extent and severity of subsidence. Study asks if subsidence indicates the aquifer system is compacting temporarily or permanently, and are the changes human-induced or tectonic.
Drought and deluge: Effects of recent climate variability on groundwater levels in eastern Arkansas [ More info] Water levels in wells completed in the Mississippi River Valley alluvial aquifer and the Sparta aquifer in eastern Arkansas respond to variability associated with annual precipitation.
Duration and current conditions graphs for selected Pennsylvania sites [ More info] Plots of streamflow averages and ground water depths for selected hydrologic sites in Pennsylvania.
Alphabetical Index of Topics
a b c d e f g h i j k l m n o p q r s t u v w x y z