Broad term for all science related to the study of the earth.
ANSS - Advanced National Seismic System [ More info] Nationa network of seismic monitoring stations coordinated with a variety of regional organizations and academic institutions.
Application of the SPARROW watershed model to describe nutrient sources and transport in the Missouri River Basin [ More info] Maps and diagrams showing how the mathematical model predicts the distribution of various pollutants within a large watershed.
Aquifer basics [ More info] Links to general information on water supply by aquifers based on rock types and to principal national aquifers by name.
Arctic National Wildlife Refuge, 1002 Area, petroleum assessment, 1998, including economic analysis [ More info] Arctic National Wildlife Refuge (ANWR) 1002 area's petroleum resource assessment. Text available in PDF and HTML formats.
Asbestos: geology, mineralogy, mining, and uses [ More info] Report on asbestos, six types of mineral fibers belonging to two mineral groups, serpentines and amphiboles,with fiber morphology, crystal structure, analytical methods, properties, mining, milling, uses, and safety factors.(PDF file,28 pp.,4.5 MB)
Ask-A-Geologist [ More info] Site to submit a question to Ask-A-Geologist where scientists research the answers to the questions, then reply directly by email.
Assessing Groundwater Availability in the High Plains Aquifer in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming [ More info] Explains concepts and methods used to determine the likely future supply of usable water in this major aquifer.
Assessing groundwater availability in the North Atlantic Coastal Plain aquifer system [ More info] Nature, history, and distinctive characteristics of this aquifer system help us to understand the likely distribution of available groundwater.
Assessing the impact of urban sprawl on soil resources in the United States using nighttime "city lights" satellite images and digital soils maps [ More info] Paper from Land Use History of North America giving results of a study to estimate the extent of developed land in the United States and the impact of development on soil resources.
Assessing the impacts of climate variability and change on the Nation's resources [ More info] Site for a USGS project under the U.S. Global Change Research Program for a national assessment of the impacts of climate variability and change on resources with links to impacts in Alaska, western U.S., public lands, and water resources.
Alphabetical Index of Topics
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