Publications

No abstract available.

Anoxygenic photosynthesis by phototrophic sulfur bacteria is prevalent in microbial mat ecosystems and in restricted, highly stratified aquatic environments. This limited distribution reflects their simultaneous requirements for an anoxic habitat, reduced sulfur to supply electrons for carbon fixation, and an appropriate light regime. Although these conditions were often satisfied in...

At a former uranium pilot mill in Grand Junction, Colorado, mine tailings and some subpile sediments were excavated to various depths to meet surface radiological standards, but residual solid-phase uranium below these excavation depths still occurs at concentrations above background. The combination of fission-track radiography and scanning electron microscope energy-dispersive X-ray...

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 879 million barrels of conventional oil and 286.2 trillion cubic feet of conventional gas in the eastern Mediterranean area.

Tracing produced water origins from wells hydraulically fractured with freshwater-based fluids is sometimes predicated on assumptions that (1) each geological formation contains compositionally unique brine and (2) produced water from recently hydraulically fractured wells resembles fresher meteoric water more so than produced water from older wells. These assumptions are not valid in...

Executive SummaryThe U.S. Geological Survey (USGS) has been using its Circular 891 for evaluating uncertainty in coal resource assessments for more than 35 years. Calculated cell tonnages are assigned to four qualitative reliability classes depending exclusively on distance to the nearest drill hole. The main appeal of this methodology, simplicity, is also its main drawback. Reliability...

The value of national coal deposits is determined for the Solid Fuel Energy Resources Assessment and Research Project through economic evaluations using hypothetical mining models. Deposits near the surface are evaluated with the U.S. Geological Survey (USGS) surface-mining model, which is patterned after the standard mining techniques and infrastructures of commercial mining projects...

No abstract available.

Using a geology-based assessment methodology, the U.S. Geological Survey estimated a mean of 2,438 billion (2.4 trillion) cubic feet of gas resources in the Williston Basin Province, in North Dakota, Montana, and South Dakota.

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean oil and gas resources of 134 million barrels of oil and 81 billion cubic feet of gas in upper Paleozoic strata of the Williston Basin Province in North Dakota, Montana, and South Dakota.

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 83 million barrels of oil and 351 billion cubic feet of gas in lower Paleozoic strata of the Williston Basin Province, North Dakota, Montana, and South Dakota.

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 161 million barrels of oil and 93 billion cubic feet of gas in the Tyler Formation of the Williston Basin Province, North Dakota.