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R. C. Milici

Publications and source records attributed to R. C. Milici.

9 recordsLinked to original sources

Coal-to-liquids: Potential impact on U.S. coal reserves

The production of liquid fuels from coal will very likely become an important part of the hydrocarbon energy mix of the future, provided that technical and environmental obstacles are overcome economically. The coal industry should be able to handle a coal-to-liquids (CTL) industry of modest size, using 60-70 million short tons or 54-64 million metric tonnes of coal per annum, without premature depletion of the country's coal reserves. However, attempts to use CTL technology to replace all petroleum imports would deplete the nation's coal reserves by the end of the century. ?? 2009 U.S. Government.

Natural Resources Research↗

Appalachian coal assessment: Defining the coal systems of the Appalachian basin

The coal systems concept may be used to organize the geologic data for a relatively large, complex area, such as the Appalachian basin, in order to facilitate coal assessments in the area. The concept is especially valuable in subjective assessments of future coal production, which would require a detailed understanding of the coal geology and coal chemistry of the region. In addition, subjective assessments of future coal production would be enhanced by a geographical information system that contains the geologic and geochemical data commonly prepared for conventional coal assessments. Coal systems are generally defined as one or more coal beds or groups of coal beds that have had the same or similar genetic history from their inception as peat deposits, through their burial, diagenesis, and epigenesis to their ultimate preservation as lignite, bituminous coal, or anthracite. The central and northern parts of the Appalachian basin contain seven coal systems (Coal Systems A-G). These systems may be defined generally on the following criteria: (1) on the primary characteristics of their paleopeat deposits, (2) on the stratigraphic framework of the Paleozoic coal measures, (3) on the relative abundance of coal beds within the major stratigraphic groupings, (4) on the amount of sulfur related to the geologic and climatic conditions under which paleopeat deposits accumulated, and (5) on the rank of the coal (lignite to anthracite). ??2005 Geological Society of America.

Special Paper of the Geological Society of America↗

Petroleum systems succeed play basis in Appalachian basin resource estimate

The US Geological Survey (USGS) periodically conducts subjective probabilistic assessments of the technically recoverable undiscovered hydrocarbon resources of the US and of the world. In addition, the USGS prepares forecasts of that portion of the technically recoverable resources that may be economic under specified conditions of supply, demand, and price. Depending on priorities, regional hydrocarbon assessments of the US are revised every 5 to 10 years. These assessments of undiscovered hydrocarbons supplement the data on hydrocarbon reserves that are reported annually by the US Department of Energy, Energy Information Administration. In between assessments, USGS assessment geologists conduct research and compile geologic and production data that may be used to improve future assessments. This new information commonly effects changes in the way the USGS defines "plays" or "assessment units" from assessment to assessment. Furthermore, USGS assessment methodology is in a constant state of evolution and changes to some degree from assessment to assessment.

Oil & Gas Journal↗

Depletion of Appalachian coal reserves - how soon?

Much of the coal consumed in the US since the end of the last century has been produced from the Pennsylvanian strata of the Appalachian basin. Even though quantities mined in the past are less than they are today, this basin yielded from 70% to 80% of the nation's annual coal production from the end of the last century until the early 1970s. During the last 25 years, the proportion of the nation's coal that was produced annually from the Appalachian basin has declined markedly, and today it is only about 40% of the total. The amount of coal produced annually in the Appalachian basin, however, has been rising slowly over the last several decades, and has ranged generally from 400 to 500 million tons (Mt) per year. A large proportion of Appalachian historical production has come from relatively few counties in southwestern Pennsylvania, northern and southern West Virginia, eastern Kentucky, Virginia and Alabama. Many of these counties are decades past their years of peak production and several are almost depleted of economic deposits of coal. Because the current major consumer of Appalachian coal is the electric power industry, coal quality, especially sulfur content, has a great impact on its marketability. High-sulfur coal deposits in western Pennsylvania and Ohio are in low demand when compared with the lower sulfur coals of Virginia and southern West Virginia. Only five counties in the basin that have produced 500 Mt or more exhibit increasing rates of production at relatively high levels. Of these, six are in the central part of the basin and only one, Greene County, Pennsylvania, is in the northern part of the basin. Decline rate models, based on production decline rates and the decline rate of the estimated, 'potential' reserve, indicate that Appalachian basin annual coal production will be 200 Mt or less by the middle of the next century. Published by Elsevier Science B.V.Much of the coal consumed in the US since the end of the last century has been produced from the Pennsylvanian strata of the Appalachian basin. Even though quantities mined in the past are less than they are today, this basin yielded from 70% to 80% of the nation's annual coal production from the end of the last century until the early 1970s. During the last 25 years, the proportion of the nation's coal that was produced annually from the Appalachian basin has declined markedly, and today it is only about 40% of the total. The amount of coal produced annually in the Appalachian basin, however, has been rising slowly over the last several decades, and has ranged generally from 400 to 500 million tons (Mt) per year. A large proportion of Appalachian historical production has come from relatively few counties in southwestern Pennsylvania, northern and southern West Virginia, eastern Kentucky, Virginia and Alabama. Many of these counties are decades past their years of peak production and several are almost depleted of economic deposits of coal. Because the current major consumer of Appalachian coal is the electric power industry, coal quality, especially sulfur content, has a great impact on its marketability. High-sulfur coal deposits in western Pennsylvania and Ohio are in low demand when compared with the lower sulfur coals of Virginia and southern West Virginia. Only five counties in the basin that have produced 500 Mt or more exhibit increasing rates of production at relatively high levels. Of these, six are in the central part of the basin and only one, Greene County, Pennsylvania, is in the northern part of the basin. Decline rate models, based on production decline rates and the decline rate of the estimated, `potential' reserve, indicate that Appalachian basin annual coal production will be 200 Mt or less by the middle of the next century.

International Journal of Coal Geology↗

Bituminous coal production in the Appalachian Basin: Past, present, and future

This report on Appalachian basin coal production consists of four maps and associated graphs and tables, with links to the basic data that were used to construct the maps. Plate 1 shows the time (year) of maximum coal production, by county. For illustration purposes, the years of maximum production are grouped into decadal units. Plate 2 shows the amount of coal produced (tons) during the year of maximum coal production for each county. Plate 3 illustrates the cumulative coal production (tons) for each county since about the beginning of the 20th century. Plate 4 shows 1996 annual production by county. During the current (third) cycle of coal production in the Appalachian basin, only seven major coal-producing counties (those with more than 500 million tons cumulative production), including Greene County, Pa.; Boone, Kanawha, Logan, Mingo, and Monongalia Counties, W.Va.; and Pike County, Ky., exhibit a general increase in coal production. Other major coal-producing counties have either declined to a small percentage of their maximum production or are annually maintaining a moderate level of production. In general, the areas with current high coal production have large blocks of coal that are suitable for mining underground with highly efficient longwall methods, or are occupied by very large scale, relatively low cost surface mining operations. The estimated cumulative production for combined bituminous and anthracite coal is about 100 billion tons or less for the Appalachian basin. In general, it is anticipated that the remaining resources will be progressively of lower quality, will cost more to mine, and will become economical only as new technologies for extraction, beneficiation, and consumption are developed, and then only if prices for coal increase.

Appalachian Basin↗

Petroleum geology of the mid-Atlantic continental margin, offshore Virginia

The Baltimore Canyon Trough, a major sedimentary basin on the Atlantic continental shelf, contains up to 18 km of Mesozoic and Cenozoic strata. The basin has been studied extensively by multichannel common depth point (CDP) seismic reflection profiles and has been tested by drilling for hydrocarbon resources in several places. The Mesozoic and Cenozoic strata contained in the basin were deposited in littoral to bathyal depositional settings and contain immature to marginally mature oil-prone and gas-prone kerogen. The more deeply buried strata of Early Mesozoic age are more likely to be thermally mature than are the younger strata with respect to hydrocarbon generation, but contain terrestrially derived coaly organic matter that would be prone to yield gas, rather than oil. An analysis of available CDP seismic reflection data has indicated that there are several potential hydrocarbon plays in the area offshore of Virginia. These include: (1) Lower Mesozoic synrift basins that appear similar to those exposed in the Appalachian Piedmont, (2) a stratigraphic updip pinchout of strata of Early Mesozoic age in the offshore region near the coast, (3) a deeply buried paleoshelf edge, where seismic reflectors dip sharply seaward; and (4) a Cretaceous/Jurassic shelf edge beneath the present continental rise. Of these, the synrift basins and Cretaceous/Jurassic shelf edge are considered to be the best targets for exploration.

Marine Geology↗