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This report documents the highly variable structure, stratigraphy, and buried topography of the outer rim of the Chesapeake Bay impact crater created by its impact and burial. Lithologies of cores are correlated with borehole geophysical logs to characterize the physical properties of the stratigraphic units and their geophysical signatures. The...

Bottom sediments have been regarded as memory banks for contaminant inputs to urban waterways. Bottom sediments accumulate by the addition of particles that enter the waterway from many sources (U.S. National Research Council, 1989). Sediments include solid contaminants, as well as contaminants from the water column that are adsorbed on...

The Edwards aquifer is one of the most productive carbonate aquifers in the Nation. The dissolution-modified, faulted limestone aquifer is the sole source of public water supply for San Antonio, Texas (fig. 1) and is the major source of water for Bexar County. In addition to providing public water supply...

The Experimental Oculina Research Reserve (EORR) is located along the shelf edge off east-central Florida in water depths of about 60 to 100 meters. It is about 7.5 km wide and 43 km long and encompasses numerous high-relief rocky pinnacles where Oculina varicosa, a fragile deep-water coral, grows. These coral...

No abstract available....

Borehole geophysical logs collected from six wells were analyzed to characterize a high-yield bedrock aquifer in the Town of Rye, New Hampshire. Video camera, caliper, fluid temperature and conductivity, natural gamma, and deviation logs were used to identify and characterize the fractured bedrock. More advanced geophysical tools included acoustic...

Three Total Petroleum Systems each consisting of one assessment unit have been identified in the Ghaba and Fahud Salt Basin Provinces of north-central Oman. One Total Petroleum System and corresponding assessment unit, the North Oman Huqf/?Q??Haushi(!) Total Petroleum System (201401) and Ghaba- Makarem Combined Structural Assessment Unit (20140101), were identified for the Ghaba Salt Basin Province (2014). In the...

No abstract available....

Quality assurance and quality control are vital parts of highway runoff water-quality monitoring projects. To be effective, project quality assurance must address all aspects of the project, including project management responsibilities and resources, data quality objectives, sampling and analysis plans, data-collection protocols, data quality-control plans, data-assessment procedures and requirements, and...

The decline of native fishes in North America is principally a result of altered habitats, and the impact of mainstream dams has accounted for many of the habitat changes. Diminished turbidity, and introduced nonnative predators were investigated as possible reasons for the decline of endangered razorback suckers Xyrauchen...

The study of lake sediments as recorders of past climate change has been a major focus of the Geologic Division's Global Change and Climate History Program. In particular, lakes of the Upper Mississippi Basin (UMB) provide some of the most detailed records of climate and environmental change during the Holocene...

On May 22, 1915, an explosive eruption at Lassen Peak, California, the southernmost active volcano in the Cascade Range, devastated nearby areas and rained volcanic ash as far away as 200 miles to the east. This explosion was the most powerful in a 1914–17 series of eruptions that were the...

Landslides threaten lives and property in every State in the Nation. To reduce the risk from active landslides, the U.S. Geological Survey (USGS) develops and uses real-time landslide monitoring systems. Monitoring can detect early indications of rapid, catastrophic movement. Up-to-the-minute or real-time monitoring provides immediate notification of landslide activity, potentially...

The Los Angeles region is underlain by a network of active faults, including many that are deep and do not break the Earth's surface. These hidden faults include the previously unknown one responsible for the devastating January 1994 Northridge earthquake, the costliest quake in U.S. history. So that structures can...

North Dakota prairies contain numerous wetlands. The complex functions of these prairie wetlands have been of interest for decades. The hydrology, water chemistry, and biological characteristics of these wetlands are highly variable because of extreme warm/cold and wet/dry conditions. The U.S. Geological Survey (USGS) has been conducting studies (fig. 1)...

In 1997, the Texas Legislature passed a comprehensive revision to the Texas Water Code. This legislation (Senate Bill 1) changed water planning in Texas from a statewide to a regional activity. By September 2001, the 16 regions created by Senate Bill 1 must produce water plans to address their water...