USGS Science⌕ Search

Geology topics

K. I. Takahashi

Publications and source records attributed to K. I. Takahashi.

10 recordsLinked to original sources
USGS2018

The use of U.S. Geological Survey CD-ROM-based petroleum assessments in undergraduate geology laboratories

Domestic oil production is declining and United States reliance on imported oil is increasing. America will be faced with difficult decisions that address the strategic, economic, and political consequences of its energy resources shortage. The geologically literate undergraduate student needs to be aware of current and future United States energy issues. The U.S. Geological Survey periodically provides energy assessment data via digitally-formatted CD-ROM publications. These publications are free to the public, and are well suited for use in undergraduate geology curricula. The U.S. Geological Survey (USGS) 1995 National Assessment of United States Oil and Gas Resources (Digital Data Series or DDS-30) (Gautier and others, 1996) is an excellent resource for introducing students to the strategies of hydrocarbon exploration and for developing skills in problem-solving and evaluating real data. This paper introduces the reader to DDS-30, summarizes the essential terminology and methodology of hydrocarbon assessment, and offers examples of exercises or questions that might be used in the introductory classroom. The USGS contact point for obtaining DDS-30 and other digital assessment volumes is also provided. Completing the sample exercises in this report requires a copy of DDS-30.

Journal of Geoscience Education↗
USGS2002

Worldwide estimates of deep natural gas resources based on the U.S. Geological Survey World Petroleum Assessment 2000

The U.S. Geological Survey recently assessed undiscovered conventional gas and oil resources in eight regions of the world outside the U.S. The resources assessed were those estimated to have the potential to be added to reserves within the next thirty years. This study is a worldwide analysis of the estimated volumes and distribution of deep (>4.5 km or about 15,000 ft), undiscovered conventional natural gas resources based on this assessment. Two hundred forty-six assessment units in 128 priority geologic provinces, 96 countries, and two jointly held areas were assessed using a probabilistic Total Petroleum System approach. Priority geologic provinces were selected from a ranking of 937 provinces worldwide. The U.S. Geological Survey World Petroleum Assessment Team did not assess undiscovered petroleum resources in the U.S. For this report, mean estimated volumes of deep conventional undiscovered gas resources in the U.S. are taken from estimates of 101 deep plays (out of a total of 550 conventional plays in the U.S.) from the U.S. Geological Survey's 1995 National Assessment of Oil and Gas Resources. A probabilistic method was designed to subdivide gas resources into depth slices using a median-based triangular probability distribution as a model for drilling depth to estimate the percentages of estimated gas resources below various depths. For both the World Petroleum Assessment 2000 and the 1995 National Assessment of Oil and Gas Resources, minimum, median, and maximum depths were assigned to each assessment unit and play; these depths were used in our analysis. Two-hundred seventy-four deep assessment units and plays in 124 petroleum provinces were identified for the U.S. and the world. These assessment units and plays contain a mean undiscovered conventional gas resource of 844 trillion cubic ft (Tcf) occuring at depths below 4.5 km. The deep undiscovered conventional gas resource (844 Tcf) is about 17% of the total world gas resource (4,928 Tcf) based on the provinces assessed and includes a mean estimate of 259 Tcf of U.S. gas from the U.S. 1995 National Assessment. Of the eight regions, the Former Soviet Union (Region 1) contains the largest estimated volume of undiscovered deep gas with a mean resource of343 Tcf.

Natural Resources Research↗
USGS1995

1995 National assessment of United States oil and gas resources; results, methodology, and supporting data

This report summarizes the results of a 3-year study of the oil and gas resources of the onshore and state waters of the United States by the U.S. Geological Survey. A parallel study of the Federal offshore is being conducted by the Minerals Management Service. Estimates are made of technically recoverable oil, including measured (proved) reserves, future additions to reserves in existing fields, and undiscovered resources. Estimates are also made of the technically recoverable conventional resources of natural gas in measured reserves, in anticipated growth of reserves in existing fields, and in undiscovered resources. Additionally, an assessment is made of recoverable resources in continuous-type (largely unconventional) accumulations in sandstones, shales, chalks, and coal beds.

Data Series↗