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E. D. Attanasi

Publications and source records attributed to E. D. Attanasi.

At least 37 records · Page 2Linked to original sources
USGS1994

US North Slope gas and Asian LNG markets

Prospects for export of liquified natural gas (LNG) from Alaska's North Slope are assessed. Projected market conditions to 2010 show that new LNG capacity beyond announced expansions will be needed to meet regional demand and that supplies will probably come from outside the region. The estimated delivered costs of likely suppliers show that Alaska North Slope gas will not be competitive. The alternative North Slope gas development strategies of transport and sale to the lower 48 states and use on the North Slope for either enhanced oil recovery or conversion to liquids are examined. The alternative options require delaying development until US gas prices increase, exhaustion of certain North Slope oil fields, or advances occur in gas to liquid fuels conversion technology.

Resources Policy↗
USGS1993

Statistics of petroleum exploration in the Caribbean, Latin America, Western Europe, the Middle East, Africa, non-communist Asia, and the southwestern Pacific

This circular presents a summary of the geographic location, amount, and results of petroleum exploration, including an atlas showing explored and delineated prospective areas through 1990. The data show that wildcat well drilling has continued through the last decade to expand the prospective area by about 40,000 to 50,000 square miles per year. However, the area delineated by 1970, which represents only about one-third of the prospective area delineated to date, contains about 80 percent of the oil discovered to date. This discovery distribution suggests that, from an overall prospective, the industry was successful in delineating the most productive areas early. The price increases of the 1970's and 1980's allowed the commercial exploration and development of fields in high-cost areas, such as the North Sea and Campos Basin, Brazil. Data on natural-gas discoveries also indicate that gas will be supplying an increasing share of the worldwide energy market. The size distribution of petroleum provinces is highly skewed. The skewed distribution and the stability in province size orderings suggest that intense exploration in identified provinces will not change the distribution of oil within the study area. Although evidence of the field-growth phenomenon outside the United States and Canada is presented, the data are not yet reliable enough for projecting future growth. The field-growth phenomenon implies not only that recent discoveries are substantially understated, but that field growth could become the dominant source of additions to proved reserves in the future.

Circular↗
USGS1991

Resource constraints in petroleum production potential

Geologic reasons indicate that the dominant position of the Middle East as a source of conventional petroleum will not be changed by new discoveries elsewhere. The share of world crude oil production coming from the Middle East could increase, within 10 to 20 years, to exceed 50 percent, under even modest increases in world consumption. Nonconventional resources of oil exist in large quantities, but because of their low production rates they can at best only mitigate extant trends. Increased production of natural gas outside the United States, however, offers an opportunity for geographically diversified energy supplies in the near future.

Science↗
USGS1989

Estimates of undiscovered conventional oil and gas resources in the United States: A part of the Nation's energy endowment

In 1987, the U.S. Geological Survey and the Minerals Management Service completed a new assessment of the undiscovered conventional resources of crude oil and natural gas in the United States. This assessment responded to a national need for such estimates, considered new geological, technologic, and economic information, and used more definitive methods of resource appraisal than previous assessments. The conventional resources assessed were (1) those considered recoverable under current technology and (2) those that could be developed and produced economically under specified price and cost relationships, excluding exploration costs. This study did not include resources from tar deposits, intractable heavy oil deposits, oil shales, gas in low-permeability (less than 0.1 millidarcy in situ) "tight" reservoirs, coal bed methane, gas in geopressured shales and brines, and natural gas hydrates (clathrates). For this study, the United States was divided into 13 regions (9 onshore and 4 offshore), including the Exclusive Economic Zone (EEZ). The 13 regions were further divided into 115 provinces (appendix A, figs. Al and A2). The resource estimates were based fundamentally upon review and analysis of petroleum geology and the exploration history of oil and gas plays in these provinces. Probability procedures were used in their derivation. Because of the uncertainty in estimating undiscovered resources, the estimated quantities are reported as a range of values that correspond to different probability levels. The undiscovered recoverable conventional resources of oil for the United States, as of January, 1, 1987, are estimated to range from 33 to 70 billion barrels, with a mean estimate of 49 billion barrels: the estimates of gas range from 307 to 507 trillion cubic feet, with a mean estimate of 399 trillion cubic feet (table 1). Range estimates correspond to 95-percent probability (19 in 20 chance) and 5-percent probability (1 in 20 chance) of there being more than those amounts, respectively. Corresponding estimates for natural gas liquids (NGL) range from 6 to 12 billion barrels, with a mean estimate of 9 billion barrels. Further, the assessed undiscovered economically recoverable oil and gas resources for the United States, as of January 1, 1987, are estimated to range from 21 to 54 billion barrels of oil and 208 to 326 trillion cubic feet of gas, corresponding to the 95-percent and 5-percent probabilities of there being more than these amounts, respectively (table 1). The mean value for oil is 35 billion barrels and for gas is 263 trillion cubic feet. Corresponding estimates for NGL range from 5 to 8 billion barrels, with a mean of 6 billion barrels. Distribution of these resources by region is shown in figure 1.

Report↗
USGS1988

Forecasting petroleum discoveries in sparsely drilled areas: Nigeria and the North Sea

Decline function methods for projecting future discoveries generally capture the crowding effects of wildcat wells on the discovery rate. However, these methods do not accommodate easily situations where exploration areas and horizons are expanding. In this paper, a method is presented that uses a mapping algorithm for separating these often countervailing influences. The method is applied to Nigeria and the North Sea. For an amount of future drilling equivalent to past drilling (825 wildcat wells), future discoveries (in resources found) for Nigeria are expected to decline by 68% per well but still amount to 8.5 billion barrels of oil equivalent (BOE). Similarly, for the total North Sea for an equivalent amount and mix among areas of past drilling (1322 wildcat wells), future discoveries are expected to amount to 17.9 billion BOE, whereas the average discovery rate per well is expected to decline by 71%. ?? 1988 International Association for Mathematical Geology.

Mathematical Geology↗
USGS1988

Observed oil and gas field size distributions: A consequence of the discovery process and prices of oil and gas

If observed oil and gas field size distributions are obtained by random samplings, the fitted distributions should approximate that of the parent population of oil and gas fields. However, empirical evidence strongly suggests that larger fields tend to be discovered earlier in the discovery process than they would be by random sampling. Economic factors also can limit the number of small fields that are developed and reported. This paper examines observed size distributions in state and federal waters of offshore Texas. Results of the analysis demonstrate how the shape of the observable size distributions change with significant hydrocarbon price changes. Comparison of state and federal observed size distributions in the offshore area shows how production cost differences also affect the shape of the observed size distribution. Methods for modifying the discovery rate estimation procedures when economic factors significantly affect the discovery sequence are presented. A primary conclusion of the analysis is that, because hydrocarbon price changes can significantly affect the observed discovery size distribution, one should not be confident about inferring the form and specific parameters of the parent field size distribution from the observed distributions. ?? 1988 International Association for Mathematical Geology.

Mathematical Geology↗
USGS1988

Physical deposit measures and commercial potential: The case of titanium-bearing heavy-mineral deposits

Physical measures of mineral deposit characteristics, such as grade and tonnage, long have been used in both subjective and analytic models to predict favorability of areas for the occurrence of mineral deposits of particular types. After a deposit has been identified, however, the explorationist must decide whether to continue data collection, begin an economic feasibility study, or abandon the prospect. The decision maker can estimate the probability that a deposit will be commercial by examining physical measures. The amount of sampling data required before such a probability estimate can be considered reliable can be determined. A logit probability model estimated from onshore titanium-bearing heavy-mineral deposit data identifies and quantifies the relative influence of a deposit's physical measures on the chances of the deposit becoming commercial. A principal conclusion that can be drawn from the analysis is that, along with a measure of deposit size, the characteristics most important in predicting commercial potential are grades of the constituent minerals. Total heavy-mineral-bearing sand grade or even total titanium grade (without data on constituent mineral grades) are poor predictors of the deposit's commercial potential. ?? 1988 International Association for Mathematical Geology.

Mathematical Geology↗
USGS1987

ECONOMICS AND THE SEARCH FOR OFFSHORE HEAVY MINERAL DEPOSITS.

This paper examines the relative importance, in terms of a deposit's commercial status, of physical characteristics of onshore titanium-bearing heavy-mineral placer deposits, and applies these findings to the search for and evaluation of offshore deposits. Results obtained by applying statistical discriminant analysis show that the characteristics most useful for predicting a deposit's commercial status are the grades of the constituent titanium minerals and the size of the deposit. Heavy-mineral grade or even the combined grades of all titanium-bearing minerals (without information and constituent mineral grades) are inferior predictors of a deposit's commercial status. When data from homogeneous regions are analyzed separately, the ability to accurately predict the deposit's commerical status improves.

Marine Mining↗
USGS1986

Regional resource depletion and industry activity: The case of oil and gas in the Gulf of Mexico

Stable and declining oil and gas prices have changed the industry's price expectations and, along with depletion of promising exploration prospects, has resulted in reduced exploration. Even with intensive additional exploration, production in most U.S. areas is expected to decline. What does this imply for the drilling and petroleum industry suppliers in particular regions? How should planners in government and the private sector project and incorporate the consequences of these changes in their strategies? This paper answers these questions for the industry operating in the offshore Gulf of Mexico. Future oil and gas production, as well as demand for offshore drilling and production facilities, are shown to depend on the size distribution of undiscovered fields, their associated production costs, and oil and gas prices. Declining well productivity is a consequence of development of progressively smaller fields so that long-run drilling demand should not decline in proportion to the expected production decline. Calculations show a substantial payoff to the drilling industry, in terms of potential demand increases, if it can develop and implement cost reducing technologies. Implications of these results for other offshore producing areas such as the North Sea are also discussed.

Socio-Economic Planning Sciences↗
USGS1985

Lognormal field size distributions as a consequence of economic truncation

The assumption of lognormal (parent) field size distributions has for a long time been applied to resource appraisal and evaluation of exploration strategy by the petroleum industry. However, frequency distributions estimated with observed data and used to justify this hypotheses are conditional. Examination of various observed field size distributions across basins and over time shows that such distributions should be regarded as the end result of an economic filtering process. Commercial discoveries depend on oil and gas prices and field development costs. Some new fields are eliminated due to location, depths, or water depths. This filtering process is called economic truncation. Economic truncation may occur when predictions of a discovery process are passed through an economic appraisal model. We demonstrate that (1) economic resource appraisals, (2) forecasts of levels of petroleum industry activity, and (3) expected benefits of developing and implementing cost reducing technology are sensitive to assumptions made about the nature of that portion of (parent) field size distribution subject to economic truncation. ?? 1985 Plenum Publishing Corporation.

Journal of the International Association for Mathe↗
USGS1984

Forecasting rates of hydrocarbon discoveries in a changing economic environment

A method is presented for the estimation of undiscovered oil and gas resources in partially explored areas where economic truncation has caused some discoveries to go unreported; therefore distorting the relationship between the observed discovery size distribution and the parent or ultimate field size distribution. The method is applied to the UK's northern and central North Sea provinces. A discovery process model is developed to estimate the number and size distribution of undiscovered fields in this area as of 1983. The model is also used to forecast the rate at which fields will be discovered in the future. The appraisal and forecasts pertain to fields in size classes as small as 24 million barrels of oil equivalent (BOE). Estimated undiscovered hydrocarbon resources of 11.79 billion BOE are expected to be contained in 170 remaining fields. Over the first 500 wildcat wells after 1 January 1983, the discovery rate in this areas is expected to decline by 60% from 15 million BOE per wildcat well to six million BOE per wildcat well. ?? 1984.

Marine and Petroleum Geology↗
USGS1982

Worth of geophysical data in natural- disaster- insurance rate setting.

Insurance firms that offer natural-disaster insurance base their rates on available information. The benefits from collecting additional data and incorporating this information to improve parameter estimates of probability distributions that are used to characterize natural-disaster events can be determined by computing changes in premiums as a function of additional data. Specifically, the worth of data can be measured by changes in consumer's surplus (the widely applied measure of benefits to consumers used in benefit-cost analysis) brought about when the premiums are adjusted. In this paper, a formal model of the process for setting insurance rates is hypothesized in which the insurance firm sets rates so as to trade off penalties of overestimation and underestimation of expected damages estimated from currently available hydrologic data. A Bayesian preposterior analysis is performed which permits the determination of the expected benefits of collecting additional geophysical data by examining the changes in expected premium rates as a function of the longer record before the data are actually collected. An estimate of the expected benefits associated with collecting more data for the representative consumer is computed using an assumed demand function for insurance. In addition, a sensitivity analysis of expected benefits to changes in insurance demand and firm rate-setting procedures is carried out. From these results, conclusions are drawn regarding aggregate benefits to all flood insurance purchasers.

Journal of Applied Meteorology and Climatology↗
USGS1981

Some regional costs of a synthetic fuel industry: The case of illinois

The Federal Government's efforts to induce development of a coal-based synthetic fuel industry include direct subsidies, tax concessions, and assurances that it will purchase the industry's output, even if above the market price. In this note it is argued that these subsidies will enable this industry to secure a region's largest and lowest-cost coal deposits and that the costs imposed on other coal users will be substantial. Moreover, because the lowest-cost coal deposits will be committed to synthetic fuels production regardless of the industry's commercial viability, distortions in regional coal markets will develop. If economic efficiency requires that the price of the resource reflect its replacement value, then a State government is justified in imposing a tax on coal destined for subsidized synthetic fuel plants. Amounts of such a tax, based on the higher costs of coal that must be accepted by other users as the result of the subsidized synthetic fuel plants' preempting the largest and lowest-cost deposits, are estimated for the case of Illinois strippable coal. ?? 1981 Annals of Regional Science.

The Annals of Regional Science↗