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Robert A. Crovelli

Publications and source records attributed to Robert A. Crovelli.

At least 19 recordsLinked to original sources
USGS2012

Analytical resource assessment method for continuous (unconventional) oil and gas accumulations - The "ACCESS" Method

The U.S. Geological Survey (USGS) periodically assesses petroleum resources of areas within the United States and the world. The purpose of this report is to explain the development of an analytic probabilistic method and spreadsheet software system called Analytic Cell-Based Continuous Energy Spreadsheet System (ACCESS). The ACCESS method is based upon mathematical equations derived from probability theory. The ACCESS spreadsheet can be used to calculate estimates of the undeveloped oil, gas, and NGL (natural gas liquids) resources in a continuous-type assessment unit. An assessment unit is a mappable volume of rock in a total petroleum system. In this report, the geologic assessment model is defined first, the analytic probabilistic method is described second, and the spreadsheet ACCESS is described third. In this revised version of Open-File Report 00-044 , the text has been updated to reflect modifications that were made to the ACCESS program. Two versions of the program are added as appendixes.

Open-File Report↗
USGS2008

Probabilistic Methodology for Estimation of Number and Economic Loss (Cost) of Future Landslides in the San Francisco Bay Region, California

The Probabilistic Landslide Assessment Cost Estimation System (PLACES) presented in this report estimates the number and economic loss (cost) of landslides during a specified future time in individual areas, and then calculates the sum of those estimates. The analytic probabilistic methodology is based upon conditional probability theory and laws of expectation and variance. The probabilistic methodology is expressed in the form of a Microsoft Excel computer spreadsheet program. Using historical records, the PLACES spreadsheet is used to estimate the number of future damaging landslides and total damage, as economic loss, from future landslides caused by rainstorms in 10 counties of the San Francisco Bay region in California. Estimates are made for any future 5-year period of time. The estimated total number of future damaging landslides for the entire 10-county region during any future 5-year period of time is about 330. Santa Cruz County has the highest estimated number of damaging landslides (about 90), whereas Napa, San Francisco, and Solano Counties have the lowest estimated number of damaging landslides (5?6 each). Estimated direct costs from future damaging landslides for the entire 10-county region for any future 5-year period are about US $76 million (year 2000 dollars). San Mateo County has the highest estimated costs ($16.62 million), and Solano County has the lowest estimated costs (about $0.90 million). Estimated direct costs are also subdivided into public and private costs.

Open-File Report↗
USGS2003

An Allocation of Undiscovered Oil and Gas Resources to Gauley River National Recreation Area and New River Gorge National River, West Virginia

The U.S. Geological Survey estimated volumes of undiscovered oil and gas resources that may underlie Gauley River National Recreation Area and New River Gorge National River in West Virginia. Using the results of an assessment of undiscovered resources from ten assessment units in the Appalachian Basin Province that include these land parcels, the USGS allocated 2.9 billion cubic feet of gas, 1.6 thousand barrels of oil, and 45 thousand barrels of natural gas liquids to part of Gauley River National Recreation Area, and 39 billion cubic feet of gas, 24 thousand barrels of oil, and 644 thousand barrels of natural gas liquids to New River Gorge National River. These allocated volumes of undiscovered resources represent potential volumes in undiscovered fields.

Open-File Report↗