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Geology topics

Emil D. Attanasi

Publications and source records attributed to Emil D. Attanasi.

At least 73 records · Page 4Linked to original sources
USGS1987

Resource assessments, geologic deposit models, and offshore minerals with an example of heavy-mineral sands

A resource assessment method for offshore minerals based on descriptive and grade-tonnage models is proposed. Historical development and applications of this method are summarized. Based on this approach, descriptive and quantitative deposit models for strand-line titanium placer deposits have been developed. Descriptive statistics were also computed using the worldwide deposit data set upon which the grade-tonnage models are based. Certain guidelines and limitations in applying onshore titanium deposit models to offshore assessment and exploration must, however, be observed. The descriptive model points out the specific features of strandline titanium placer deposits which can be of use in selection of areas for exploration; the grade-tonnage models display the expected size distribution for this type of deposit. Used with an estimate of expected number of deposits, this information can be applied to quantify probable values associated with deposits of this type within a given area.

NATO Science Series↗
USGS1987

Statistics of petroleum exploration in the non-Communist world outside the United States and Canada

The search for petroleum has expanded to include most countries in the world. From January 1, 1950, through 1980, about 160,000 crew months were spent in geologic and geophysical exploration in a study area that includes all nonCommunist countries outside the United States and Canada. By the end of 1982, almost 27,000 wildcat wells had been drilled in this study area; these and other pre-1983 wells delineated a prospective area of 1.56 million square miles in which about 836 billion barrels of ultimately recoverable crude oil has been found, 62 percent of it since 1950. The delineated prospective area is still expanding at a rate of 56,000 square miles per year (60 square miles per wildcat well) for the study area, and it is increasing in nearly every country in the study area. Maps of the delineated prospective area in each country show that in most countries, only a small part of the national territory has been explored. In spite of the expansion of the searched area, however, the rate of discovery has declined significantly from 22 million barrels per exploratory well in the 1950's to 8 million barrels per exploratory well in the 1970's.

Circular↗
USGS1984

Offshore exploration and industry change: The case of the Gulf of Mexico

This paper considers industry structure and the exploration performance (by size class of operator) of firms searching for oil and gas in the U.S. Gulf of Mexico. It also tracks the changes in industry structure that have occurred in response to a decline in the quality of remaining prospects in the area. Data presented indicate that because vertically integrated majors dominated in exploration in the early years of the Gulf of Mexico exploration history, they were able to discover 86% of the total hydrocarbons discovered through 1975. However, the data also show a dynamic relationship between the structure of the industry operating in an area and the quality of remaining prospects. The relative share of both credited discoveries and wildcat wells of nonmajor operators has increased as exploration in the gulf proceeded. For example, in state-owned waters from 1951 to 1955, major inns accounted for 85% of all wildcat wells drilled, whereas from 1971 to 1975 these firms accounted for only 30% of the wildcat wells. During these same two periods in the federal Gulf of Mexico, the majors' share of wildcats fell from 98% to 70%.

Journal of Petroleum Technology↗
USGS1984

Government investment in mineral resource information on leasable public lands: The case of strippable coal

A scheme is presented to aid the government in estimating the net benefits, in terms of itsrecovery of expected rents, of performing various levels of exploration of mineral tracts prior to leasing and making such information available to potential bidders. Conditions are identified where the government will profit by investment in geologic data that are collected and provided to potential bidders without reducing the expected returns to bidders. Expected benefits of an optimal data-collection program depend on (1) the degree of bidder risk aversion, (2) the expected degree of lease competition and (3) unique lease tract factors that determine economic rents—thickness of seams, proximity to markets, extraction costs, and the spatial correlation characteristics of data. The effects of price uncertainty and government policies affecting market stability on the value of information are also discussed.

Resources and Energy↗
USGS1981

Economics and petroleum resource appraisal: The case of the Permian basin:

Estimates of oil and gas resources typically are presented in terms of proved and undiscovered resources. This paper presents a methodology for incorporating economic considerations into resource appraisals for petroleum basins. A cost algorithm is used to calculate estimates of the costs of finding and developing undiscovered oil and gas fields in the Permian basin. The sensitivity of the resource estimates to variations in values of the variables in the costing model was investigated, and the results of this analysis are presented. The model indicates that at prices up to $40/bbl, the total reserves of oil and gas in barrels-of-oil equivalent (BOE's) from future discoveries will be less than 15% of the estimated ultimate recovery from fields discovered before Jan. 1 1975. Only discoveries to a depth of 20,000 ft were included.

Journal of Petroleum Technology↗
USGS1979

Risk preferences and flood insurance

A detailed theoretical model characterizing the individual's decision to purchase flood insurance is specified and the magnitude of the risk parameter is estimated using data based on transactions of flood insurance purchases. Empirical results for several samples of this subset of the general population indicated that consumers exhibited a relatively uniform degree of risk aversion across various localities where different hydrologic and economic conditions prevailed. While the estimates presented should not be directly extrapolated to the entire population located in a flood prone area, they provide evidence that parameters determining an individual's and/or community's willingness to pay for flood protection can be measured.

American Journal of Agricultural Economics↗
USGS1979

Nature of firm expectations in petroleum exploration

Recent interest in the state of the United States domestic petroleum industry has resulted in an increased concern regarding the ability of current large- scale econometric models to provide useful predictions about supply price sensitivity and about the effects of differing policy options on future supply. The petroleum industry's exploration and reserve response functions appear to have eluded traditional modeling approaches. Properties of firm exploration behavior are obscured when highly aggregated data are used. Data pertaining to different geographical areas are frequently combined using dummy variables to denote characteristics peculiar to a region. In these models price tends to be more related to the quality of the crude oil than to incremental costs of exploration and development of individual deposits. The effect of price changes on expected supplies is clearly moderated by the level of resource depletion for a particular basin. A major obstacle to carrying out a less aggregated analysis has been the lack of data on specific basins, but another obstacle has been the belief that field behavior is too erratic to model successful.

Land Economics↗
USGS1977

Field expectations and the determination of wildcat drilling

There is currently some dissatisfaction with macroeconomic approaches to modeling the supply of domestic crude oil. One problem that has been pointed out is that the estimated supply responses of new discoveries brought about by price increases appear to be unrealistically high. Because data frequently used in these models are highly aggregated over time and include diverse geologic regions, this criticism may not be unwarranted. Moreover, with highly aggregated data testable hypotheses relating to operator behavior at the field level are limited. Because of the somewhat decentralized nature of firm decision making, operator field behavior significantly affects the wildcat drilling rate and hence the interarrival times, i.e., temporal sequence, of expected discoveries.

Southern Economic Journal↗
USGS1975

Expectations, market structure, and sequential bid pricing

Public agencies are frequently constrained to procure goods and services in sealed tender markets. Pricing decisions of firms participating in such markets have been analyzed for both static and dynamic situations. As might be anticipated, the decision rules obtained in these analyses depend in an integral way on the firm's perception of the behavior of other market participants. It is this aspect of the pricing problem to which our paper is directed.

Southern Economic Journal↗