Publications

Sustained increases in energy prices have focused attention on gas resources in low permeability shale or in coals that were previously considered economically marginal. Daily well deliverability is often relatively small, although the estimates of the total volumes of recoverable resources in these settings are large. Planning and development decisions for extraction of such resources...

Siliciclastic and calcareous sedimentary rocks of early Late Cretaceous age in the Western Interior of the United States have been assigned to, in ascending order, the Graneros Shale, Greenhorn Formation, Carlile Shale, Niobrara Formation, and their lateral equivalents (including members of the Frontier Formation and overlying formations). This sequence of formations was deposited...

Tertiary (3.78 Ma to 3.65 Ma) biotite-K-feldspar porphyritic bodies intrude Tertiary, poorly consolidated lacustrine sedimentary rocks in the Beiya mineral district in southwestern China. The intrusives are characterized by a microcrystalline and vitreous-cryptocrystalline groundmass, by replacement of some tabular K-feldspar phenocrysts with microcrystalline chlorite and calcite, and by...

We interpret Global Positioning System (GPS) measurements in the northwestern United States and adjacent parts of western Canada to describe relative motions of crustal blocks, locking on faults and permanent deformation associated with convergence between the Juan de Fuca and North American plates. To estimate angular velocities of the oceanic Juan de Fuca and Explorer plates and...

In 2003, the U.S. Geological Survey (USGS) completed an assessment of the oil and gas resource potential of the San Joaquin Basin Province of California (fig. 1.1). The assessment is based on the geologic elements of each Total Petroleum System defined in the province, including hydrocarbon source rocks (source-rock type and maturation and hydrocarbon generation and migration), reservoir...

No abstract available.

Selected terms of particular importance to the U.S. Geological Survey assessment of undiscovered resources in total petroleum systems are defined here. The definitions are intended to be generally explanatory rather than strictly technical. No attempt has been made to include a detailed listing of common industry definitions.

Geologic, production, and exploration/discovery-history data are used by the U.S. Geological Survey to aid in the assessment of petroleum resources. These data, as well as the broad knowledge and experience of the assessing geologists, are synthesized to provide, for each assessment unit, geologic and exploration models upon which estimates are made of the number and sizes of...

The U.S. Geological Survey has developed two Monte Carlo programs for assessment of undiscovered conventional oil and gas resources. EMCEE (for Energy Monte Carlo) and Emc2 (for Energy Monte Carlo program 2) are programs that calculate probabilistic estimates of undiscovered resources based on input distributions for numbers and sizes of undiscovered fields. Emc2 uses specific types of

The Golden State got its nickname from the Sierra Nevada gold that lured so many miners and settlers to the West, but California has earned much more wealth from so-called “black gold” than from metallic gold. The San Joaquin Valley has been the principal source for most of the petroleum produced in the State during the past 145 years. In attempting to assess future additions to...

An exposure of the Lower Cretaceous Fortress Mountain and Torok Formations along the Siksikpuk River in north-central Alaska provides a rare opportunity to observe the stratigraphic contact between these two formations and to interpret the depositional facies and sequence stratigraphy of the exposed strata. The Fortress Mountain Formation at the base of the measured section includes...

The foothills of the Brooks Range contain an enormous accumulation of zinc (Zn) in the form of zinc sulfide and barium (Ba) in the form of barite in Carboniferous shale, chert, and mudstone. Most of the resources and reserves of Zn occur in the Red Dog deposit and others in the Red Dog district; these resources and reserves surpass those of most deposits worldwide in terms of size and...