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Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean continuous resources of 0.8 billion barrels of oil and 16 trillion cubic feet of gas in the Upper Jurassic Smackover Formation of the onshore U.S. Gulf Coast region.
Using a geology-based assessment methodology, the U.S. Geological Survey (USGS) estimated undiscovered, technically recoverable mean resources of 16 million barrels of oil and 348 billion cubic feet of gas in conventional reservoirs of the Norphlet Formation in the U.S. Gulf Coast region.
The U.S. Geological Survey provided technical support to the Agency for Toxic Substances and Disease Registry for site selection and sample collection and analysis in a 2012 investigation of groundwater quality from 29 private domestic water-supply wells in the vicinity of petroleum production in southwestern Indiana. Petroleum hydrocarbons, oil and grease, aromatic volatile organic compounds, methane concentrations greater than 8,800 micrograms per liter, chloride concentrations greater than 250 milligrams per liter, and gross alpha radioactivity greater than 15 picocuries per liter were reported in the analysis of groundwater samples from 11 wells.
Oil and gas trapped in Lower Silurian "Clinton" sands and Medina Group sandstone constitute a regional hydrocarbon accumulation that extends 425 mi in length from Ontario, Canada to northeastern Kentucky. The 125-mi width of the accumulation extends from central Ohio eastward to western Pennsylvania and west-central New York. Lenticular and intertonguing reservoirs, a gradual eastward decrease in reservoir porosity and permeability, and poorly segregated gas, oil, and water in the reservoirs make it very difficult to recognize clear-cut geologic- and production-based subdivisions in the accumulation that are relevant to resource assessment. However, subtle variations are recognizable that permit the regional accumulation to be subdivided into three tentative parts: a western gas-bearing part having more or less discrete fields; an eastern gas-bearing part having many characteristics of a basin-centered accumulation; and a central oil- and gas-bearing part with "hybrid" fields that share characteristics of both discrete and basin-centered accumulation. A data set of 25 oil and gas fields is used in the report to compare selected attributes of the three parts of the regional accumulation. A fourth part of the regional accumulation, not discussed here, is an eastern extension of basin-centered accumulation having local commercial gas in the Tuscarora Sandstone, a proximal facies of the Lower Silurian depositional system. A basin-centered gas accumulation is a regionally extensive and commonly very thick zone of gas saturation that occurs in low-permeability rocks in the central, deeper part of a sedimentary basin. Another commonly used term for this type of accumulation is deep-basin gas accumulation. Basin-centered accumulation is a variety of continuous-type accumulation. The "Clinton" sands and Medina Group sandstone part of the basin-centered gas accumulation is characterized by: a) reservoir porosity ranging from about 5 to 10 percent; b) reservoir permeability equal to or less than 0.1 mD; c) low reservoir water saturation and an average water yield per well less than about 9 to 13 BW/MMCFG; d) a broadly defined updip water-block trap; e) underpressured reservoirs with a gradient ranging from 0.25 to 0.35 psi/ft; and f) reservoir temperature of at least 125° F (52° C). Other than for historical and location purposes, the term field has little or no meaning as an assessment unit for the regional accumulation. In practice, each designated field represents a production sweet spot having relatively high EURs per well that in turn merges with surrounding gas-productive regions that are generally larger in area but have lower EURs per well. This important feature of the Lower Silurian regional accumulation, whereby most wells drilled into it are gas productive, must be considered when assessing its potential for remaining recoverable gas resources. Most of the remaining gas resources reside in "Clinton" sands and Medina Group sandstone in the basin-centered part of the accumulation where as much as several tens of TCF of natural gas may be technically recoverable. The Tuscarora Sandstone in the eastern extension of the basin-centered part of the accumulation underlies a very large area and, although commonly characterized by very low porosity and permeability and low-Btu gas, probably contains additional gas resources. Remaining undiscovered recoverable gas and oil resources in the discrete and hybrid parts of the accumulation are primarily located beneath Lake Erie.
Using a geology-based assessment methodology, the U.S. Geological Survey assessed a technically recoverable mean resource of 8.3 trillion cubic feet of unconventional tight gas in the Zona Glauconitica of the Magallanes Basin Province, Chile.
Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 5.27 trillion cubic feet of coalbed gas in the Karoo Basin Province.
Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 429 million barrels of continuous oil and 8 trillion cubic feet of continuous gas in the Beetaloo Basin of northern Australia.
Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 13.4 billion barrels of oil and 244.4 trillion cubic feet of gas in nine geologic provinces of China.
Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean conventional resources of 7.3 billion barrels of oil and 463.7 trillion cubic feet of gas within the Barents Sea area.
Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean conventional resources of 13.3 billion barrels of oil and 111 trillion cubic feet of gas in the central Arabian Peninsula.
Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean conventional resources of 208 million barrels of oil and 4.1 trillion cubic feet of gas in the greater Carpathian area.
GP Workbench is an open-source general-purpose geophysical data processing software package written primarily for ground penetrating radar (GPR) data. It also includes support for several USGS prototype electromagnetic instruments such as the VETEM and ALLTEM. The two main programs in the package are GP Workbench and GP Wave Utilities. GP Workbench has routines for filtering, gridding, and migrating GPR data; as well as an inversion routine for characterizing UXO (unexploded ordinance) using ALLTEM data. GP Workbench provides two-dimensional (section view) and three-dimensional (plan view or time slice view) processing for GPR data. GP Workbench can produce high-quality graphics for reports when Surfer 8 or higher (Golden Software) is installed. GP Wave Utilities provides a wide range of processing algorithms for single waveforms, such as filtering, correlation, deconvolution, and calculating GPR waveforms. GP Wave Utilities is used primarily for calibrating radar systems and processing individual traces. Both programs also contain research features related to the calibration of GPR systems and calculating subsurface waveforms. The software is written to run on the Windows operating systems. GP Workbench can import GPR data file formats used by major commercial instrument manufacturers including Sensors and Software, GSSI, and Mala. The GP Workbench native file format is SU (Seismic Unix), and subsequently, files generated by GP Workbench can be read by Seismic Unix as well as many other data processing packages.
The extended abstracts in this volume are summaries of the papers presented orally and as posters in the second V. E. McKelvey Forum on Mineral and Energy Resources, entitled "USGS Research on Energy Resources-1986." The Forum has been established to improve communication between the USGS and the earth science community by presenting the results of current USGS research on nonrenewable resources in a timely fashion and by providing an opportunity for individuals from other organizations to meet informally with USGS scientists and managers. It is our hope that the McKelvey Forum will help to make USGS programs more responsive to the needs of the earth science community, particularly the mining and petroleum industries, and Win foster closer cooperation between organizations and individuals. The Forum was named after former Director Vincent E. McKelvey in recognition of his lifelong contributions to research, development, and administration in mineral and energy resources, as a scientist, as Chief Geologist, and as Director of the U.S. Geological Survey. The Forum will be an annual event, and its subject matter will alternate between mineral and energy resources. We expect that the format will change somewhat from year to year as various approaches are tried, but its primary purpose will remain the same: to encourage direct communication between USGS scientists and the representatives of other earth-science related organizations. Energy programs of the USGS include oil and gas, coal, geothermal, uranium-thorium, and oil shale; work in these programs spans the national domain, including surveys of the offshore Exclusive Economic Zone. The topics selected for presentation at this McKelvey Forum represent an overview of the scientific breadth of USGS research on energy resources. They include aspects of petroleum occurrence in Eastern United States rift basins, the origin of magnetic anomalies over oil fields, accreted terranes and energy-resource implications, coal quality, geothermal energy sources, integrated geology and chemistry in uranium-deposit studies, and interpretations of sea-floor geology seen in reconnaissance-scale sidescan-sonar mosaics of the Gulf of Mexico and west coast Exclusive Economic Zone. Data are presented that are being used in building models of geothermal energy settings, basin histories, and the occurrence of energy resources. In addition to the technical sessions presenting the results of USGS research, each congressionally mandated USGS Mineral Resource Program has a display outlining plans and progress. We are all excited about this continuing opportunity to disseminate and discuss our research with our colleagues in industry and academia, and we welcome your suggestions on improving this series of Forums.
The U.S. Geological Survey, using a geology-based assessment methodology, estimated mean volumes of technically recoverable, conventional, undiscovered petroleum resources at 218 million barrels of crude oil, 4.1 trillion cubic feet of natural gas, and 94 million barrels of natural gas liquids for the Azov-Kuban Basin Province as part of a program to estimate petroleum resources for priority basins throughout the world.
Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean undiscovered, technically recoverable continuous resources of 35.1 trillion cubic feet of gas in the Amu Darya Basin Province of Turkmenistan, Uzbekistan, Iran, and Afghanistan.
Ulaanbaatar, the capital city of Mongolia (fig. 1), is dependent on groundwater for its municipal and industrial water supply. The population of Mongolia is about 3 million people, with about one-half the population residing in or near Ulaanbaatar (World Population Review, 2016). Groundwater is drawn from a network of shallow wells in an alluvial aquifer along the Tuul River. Evidence indicates that current water use may not be sustainable from existing water sources, especially when factoring the projected water demand from a rapidly growing urban population (Ministry of Environment and Green Development, 2013). In response, the Government of Mongolia Ministry of Environment, Green Development, and Tourism (MEGDT) and the Freshwater Institute, Mongolia, requested technical assistance on groundwater modeling through the U.S. Army Corps of Engineers (USACE) to the U.S. Geological Survey (USGS). Scientists from the USGS and USACE provided two workshops in 2015 to Mongolian hydrology experts on basic principles of groundwater modeling using the USGS groundwater modeling program MODFLOW-2005 (Harbaugh, 2005). The purpose of the workshops was to bring together representatives from the Government of Mongolia, local universities, technical experts, and other key stakeholders to build in-country capacity in hydrogeology and groundwater modeling. A preliminary steady-state groundwater-flow model was developed as part of the workshops to demonstrate groundwater modeling techniques to simulate groundwater conditions in alluvial deposits along the Tuul River in the vicinity of Ulaanbaatar. ModelMuse (Winston, 2009) was used as the graphical user interface for MODFLOW for training purposes during the workshops. Basic and advanced groundwater modeling concepts included in the workshops were groundwater principles; estimating hydraulic properties; developing model grids, data sets, and MODFLOW input files; and viewing and evaluating MODFLOW output files. A key to success was developing in-country technical capacity and partnerships with the Mongolian University of Science and Technology; Freshwater Institute, Mongolia, a non-profit organization; United Nations Educational, Scientific and Cultural Organization (UNESCO); the Government of Mongolia; and the USACE.
The U.S. Geological Survey (USGS) assessed the potential for undiscovered oil and gas resources of the Yenisey-Khatanga Basin Province as part of the USGS Circum-Arctic Resource Appraisal. The province is situated between the Taimyr-Kara high (Kara block, Central Taimyr fold belt, and South Taimyr fold belt) and the Siberian craton. The two assessment units (AUs) defined for this study—the Khatanga Saddle AU and the Yenisey-Khatanga Basin AU were assessed for undiscovered, technically recoverable, conventional resources. The estimated mean volumes of undiscovered resources for the Yenisey-Khatanga Basin Province are ~5.6 billion barrels of crude oil, ~100 trillion cubic feet of natural gas, and ~2.7 billion barrels of natural-gas liquids, all north of the Arctic Circle.
The U.S. Geological Survey has evaluated the potential for undiscovered oil and gas resources of the Tunguska Basin Province as part of the Circum-Arctic Resource Appraisal (CARA). The Tunguska Basin Province includes an area of approximately 904,000 km 2 ; less than half the area of the province lies north of the Arctic Circle. The Tunguska Basin Province includes a large part of the Siberian craton and consists of several subbasins. The province is almost completely covered by Permian to Triassic volcanic rocks. Although some oil and gas fields have been discovered and produced in the province south of the Arctic Circle, no discoveries have been made north of the Arctic Circle as of 2008. The part of this province lying north of the Arctic Circle was evaluated for undiscovered, technically recoverable, conventional oil and gas resources. Because of a low geologic probability for the occurrence of significant oil and gas accumulations (50 million barrels of oil equivalent or more), the Tunguska Basin Province north of the Arctic Circle was not quantitatively assessed as part of CARA.