Publications

In northwest Arizona, the relatively unextended Colorado Plateau gives way abruptly to the highly extended Colorado River extensional corridor within the Basin and Range province along a system of major west-dipping normal faults, including the Grand Wash fault zone and South Virgin–White Hills detachment fault. Large growth-fault basins developed in the hanging walls of these faults...

Elastic velocities and hydraulic permeability of gas hydrate-bearing sediments strongly depend on how gas hydrate accumulates in pore spaces and various gas hydrate accumulation models are proposed to predict physical property changes due to gas hydrate concentrations. Elastic velocities and permeability predicted from a cementation model differ noticeably from those from a pore-filling...

The U.S. Geological Survey (USGS) has completed an assessment of the undiscovered oil and associated gas resources of the Upper Devonian to Lower Mississippian Bakken Formation in the U.S. portion of the Williston Basin of Montana and North Dakota and within the Williston Basin Province. The assessment is based on geologic elements of a total petroleum system (TPS), which include (1)...

Elastic velocities of water-saturated sandstones depend primarily on porosity, effective pressure, and the degree of consolidation. If the dry-frame moduli are known, from either measurements or theoretical calculations, the effect of pore water on velocities can be modeled using the Gassmann theory. Kuster and Toksoz developed a theory based on wave-scattering theory for a variety of...

The purpose of the U.S. Geological Survey's (USGS) World Oil and Gas Assessment is to develop geologically based hypotheses regarding the potential for additions to oil and gas reserves in priority areas of the world. The U.S. Geological Survey (USGS) completed an assessment of the undiscovered oil and gas potential of the North Cuba Basin. The assessment is based on the geologic...

Gas-hydrate resource assessment on the Alaska North Slope using 3-D and 2-D seismic data involved six important steps: (1) determining the top and base of the gas-hydrate stability zone, (2) 'tying' well log information to seismic data through synthetic seismograms, (3) differentiating ice from gas hydrate in the permafrost interval, (4) developing an acoustic model for the reservoir and...

Using a geology-based assessment method, the U.S. Geological Survey estimated mean undiscovered volumes of 3.8 billion barrels of undiscovered oil, 3.7 trillion cubic feet of associated/dissolved natural gas, and 0.2 billion barrels of undiscovered natural gas liquids in the Williston Basin Province, North Dakota, Montana, and South Dakota. (See “Introduction” in Fact Sheet for...

The U.S. Geological Survey (USGS) recently completed the first assessment of the undiscovered technically recoverable gas-hydrate resources on the North Slope of Alaska. Using a geology-based assessment methodology, the USGS estimates that there are about 85 trillion cubic feet (TCF) of undiscovered, technically recoverable gas resources within gas hydrates in northern Alaska.

This guidebook includes papers on various aspects of resource evaluation, exploration, petrophysics, reservoir potential, well deliverability and drilling and completion technology. As new shale plays are explored for and developed, it is important to learn from analogs and case histories, including those from outside the Rocky Mountain region. While the emphasis is on natural gas, we...

No abstract available.

An area between the towns of Winnemucca and Battle Mountain in northwestern Nevada, termed the arkosic triangle, includes the type areas of the middle to upper Paleozoic Inskip Formation and Havallah sequence, the Upper Devonian to Mississippian Harmony Formation, the Sonoma orogeny, and the Golconda thrust. According to an extensive body of scientific literature, the Havallah sequence...

The general location and age of more than 33,500 mostly foraminifer samples from Chevron surface localities in nearly 600 U.S. Geological Survey (USGS) 7.5' quadrangles from California were provided by Brabb and Parker (2003). Barren and non-diagnostic samples plus many that have no paleontologic information were omitted to provide a revised list for more than 27,000 of these samples by...