Maps

This map presents the results of U.S. Geological Survey (USGS) geologic bedrock mapping studies in the mostly glacier covered Atlin 1:250,000-scale quadrangle, northern southeastern Alaska. These studies are part of a long-term systematic effort by the USGS to provide bedrock geologic and mineral-resource information for all of southeastern Alaska, covering all of the Tongass National Forest (incl

This map depicts the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity for September 2008. Potentiometric contours are based on water-level measurements collected at 589 wells during the period September 15-25, near the end of the wet season. Some contours are inferred from previous potentiometric-surface maps with larger well networ

This map depicts the potentiometric surface of the Upper Floridan aquifer in the St. Johns River Water Management District and vicinity for May 2008. Potentiometric contours are based on water-level measurements collected at 567 wells during the period May 6-May 27, near the end of the dry season. Some contours are inferred from previous potentiometric-surface maps with larger well networks. The p

The U.S. Geological Survey (USGS) analyzed changes in the configuration of land and water in coastal Louisiana by using a sequential series of 14 data sets summarizing land and water areas from 1956 to 2006. The purpose of this study is to provide a spatially and temporally consistent source of quantitative information on land area across coastal Louisiana, broken into three physiographic province

The Floridan aquifer system consists of the Upper and Lower Floridan aquifers separated by the middle confining unit. The middle confining unit and the Lower Floridan aquifer in west-central Florida generally contain highly mineralized water. The water-bearing units containing fresh water are herein referred to as the Upper Floridan aquifer. The Upper Floridan aquifer is the principal source of wa

The surficial aquifer system is the major source of freshwater for public water supply in Palm Beach County, Florida, yet many previous studies of the hydrogeology of this aquifer system have focused only on the eastern one-half to one-third of the county in the more densely populated coastal area (Land and others, 1973; Swayze and others, 1980; Swayze and Miller, 1984; Shine and others, 1989). Po

Changes in the area and volume of polar ice sheets are intricately linked to changes in global climate, and the resulting changes in sea level could severely impact the densely populated coastal regions on Earth. Melting of the West Antarctic part alone of the Antarctic ice sheet would cause a sea-level rise of approximately 6 meters (m). The potential sea-level rise after melting of the entire An

No abstract available.

During 1996 to 2000, the Bureau of Land Management, National Park Service, Environmental Protection Agency, United States Department of Agriculture (USDA) Forest Service, and the U.S. Geological Survey (USGS) developed a coordinated strategy to (1) study the environmental effects of historical mining on Federal lands, and (2) remediate contaminated s

This dataset represents surficial geologic mapping of the Hughes quadrangle, Alaska. It is used to create the mapsheet in MF-2408, which shows surficial deposits of the 1:250,000 scale Hughes quadrangle in north central Alaska.

No abstract available.

No abstract available.