Coal quality loss from acquisition to analysis; a preliminary time study
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Several approaches are used to assess the performance of the built environment following an earthquake -- preliminary damage surveys conducted by professionals, detailed studies of individual structures, and statistical analyses of groups of structures. Reports of damage that are issued by many organizations immediately following an earthquake play a key role in directing subsequent detailed investigations. Detailed studies of individual structures and statistical analyses of groups of structures may be motivated by particularly good or bad performance during an earthquake. Beyond this, practicing engineers typically perform stress analyses to assess the performance of a particular structure to vibrational levels experienced during an earthquake. The levels may be determined from recorded or estimated ground motions; actual levels usually differ from design levels. If a structure has seismic instrumentation to record response data, the estimated and recorded response and behavior of the structure can be compared.
This manuscript is based on a geologic and topographic reconnaissance survey, made during the summer of 1903, of an important placer-gold district in the northeastern part of Seward Peninsula. The report is accompanied by a reconnaissance map by Mr. D. C. Witherspoon, topographer, under whose directions the field operations were carried out. Surveys were begun in Seward Peninsula in 1899, soon after the discovery of the rich placers of Nome, and, in view of the great economic importance of the field, have been extended as rapidly as the appropriations permitted. It was early recognized that here, as elsewhere in Alaska, it would be better to obtain general topographic and geologic results, to be immediately available to the mining public, than to attempt exhaustive surveys and studies of small areas. This has been the guiding policy in formulating and executing the plans. As a result, there have been issued a number of publications (including reconnaissance maps) which, though only of a preliminary character, have been, because of their timeliness, of much value to the mining public. With the appearance of the following report this first epoch in the surveys will have closed, for there will be available complete reconnaissance reports and maps of the entire Seward Peninsula. These general reports and maps should be followed by more detailed surveys; these have been begun, and it is purposed to carry them forward as rapidly as circumstances will permit. In taking up areas for detailed investigations the attempt will be made to study first those of greatest economic interest.
A coal resource assessment team from the U.S. Geological Survey (USGS), in cooperation with the Armenian Department of Underground Resources (DUR) and elements of the Ministry of Energy and Fuel, has completed an initial visit to Armenia under the auspices of the U.S. Agency for International Development JUSAID). The visit included discussions of the coal resources, identification of problems associated with on-going exploration and development activities, and field visits to selected solid fuel areas. The USGS team will return in November with a draft of the final report for discussion of conclusions and recommendations with Armenian counterparts, representatives of USAID, and the American Embassy. The final report, which will contain tabulated coal-sample analytical results and detailed recommendations, will be submitted to the USAID by the end of December 1993. Preliminary conclusions are that: 1) Armenia has usable deposits of coal that could form a viable, though relatively small, component of Armenia's energy budget; 2) on-going exploration and development activities must be augmented and expedited to increase understanding of the coal resource potential and subsequent utilization; 3) deficiencies in supplies (primarily fuel) and equipment (replacement of aging parts and units) have greatly reduced the gathering of necessary resource data; and 4) training of Armenian counterparts in conducting and managing coal exploration activities is desirable.
In attempting the collection of data for the statement of the commercial value of the mineral waters of the country for publication in the report on the Mineral Resources of the United States, 1883 and 1884, it was necessary as a prerequisite to have a list of the springs from which these waters are derived. An examination of the few general works on the subject very soon showed that all existing lists were incomplete. The tables given in this paper were therefore compiled, as the first step in the preparation of the mineral spring statistics of the. United States, They were omitted from the paper published in Mr. Williams's report, for want of space. Since the appearance of that report they have been revised and, with the addition of such analyses as could be obtained, prepared for publication as a bulletin of the Survey.
The Hueco Bolson, as defined in this report, is in the extreme western part of Texas and includes that part of El Paso County between the Franklin and Hueco Mountains north of the Rio Grande.
The Ruth Mine and mill are located in the western Mojave Desert in Inyo County, California (fig. 1). The mill processed gold-silver (Au-Ag) ores mined from the Ruth Au-Ag deposit, which is adjacent to the mill site. The Ruth Au-Ag deposit is hosted in Mesozoic intrusive rocks and is similar to other Au-Ag deposits in the western Mojave Desert that are associated with Miocene volcanic centers that formed on a basement of Mesozoic granitic rocks (Bateman, 1907; Gardner, 1954; Rytuba, 1996). The volcanic rocks consist of silicic domes and associated flows, pyroclastic rocks, and subvolcanic intrusions (fig. 2) that were emplaced into Mesozoic silicic intrusive rocks (Troxel and Morton, 1962). The Ruth Mine is on Federal land managed by the U.S. Bureau of Land Management (BLM). Tailings from the mine have been eroded and transported downstream into Homewood Canyon and then into Searles Valley (figs. 3, 4, 5, and 6). The BLM provided recreational facilities at the mine site for day-use hikers and restored and maintained the original mine buildings in collaboration with local citizen groups for use by visitors (fig. 7). The BLM requested that the U.S. Geological Survey (USGS), in collaboration with Chapman University, measure arsenic (As) and other geochemical constituents in soils and tailings at the mine site and in stream sediments downstream from the mine in Homewood Canyon and in Searles Valley (fig. 3). The request was made because initial sampling of the site by BLM staff indicated high concentrations of As in tailings and soils adjacent to the Ruth Mine. This report summarizes data obtained from field sampling of mine tailings and soils adjacent to the Ruth Mine and stream sediments downstream from the mine on June 7, 2009. Our results permit a preliminary assessment of the sources of As and associated chemical constituents that could potentially impact humans and biota.
This is the Web version of a CD-ROM publication. This report consists of summary major compilations and syntheses accomplished in the six-year project through April 2003 for the study on the Mineral Resources, Metallogenesis, and Tectonics of Northeast Asia (Eastern and Southern Siberia, Mongolia, Northeastern China, South Korea, and Japan). The major scientific goals and benefits of the project are to: (1) provide a comprehensive international data base on the mineral resources of the region that is the first, extensive knowledge available in English; (2) provide major new interpretations of the origin and crustal evolution of mineralizing systems and their host rocks, thereby enabling enhanced, broad-scale tectonic reconstructions and interpretations; and (3) promote trade and scientific and technical exchanges between the North America and Northeast Asia. Data from the project are providing sound scientific data and interpretations for commercial firms, governmental agencies, universities, and individuals that are developing new ventures and studies in the project area, and for land-use planning studies that deal with both mineral potential issues. Northeast Asia has vast potential for known and undiscovered mineral deposits; however, little information existed in English in the West until publication of products from this project. Consequently, data and interpretations from the project are providing basic knowledge for major scientific, commercial, national, and international endeavors by other interested individuals and groups.
The drilling and logging activity described in this report was undertaken in August 1979, as part of the Energy Lands program of the U.S. Geological Survey. The general objectives of the project, of which this work is a part, are to provide an understanding of the nature, location, and extent of the engineering and environmental concerns in potential coal-development areas of the Cook Inlet region, Alaska. The geotechnical and geophysical logs presented in this report provide some of the basic physical-property and engineering data needed to evaluate geologic hazards, and to predict the response of geologic materials to large-scale coal mining and related development in the Capps coal field of the Beluga coal area. Specifically, the information may be used to help determine such things as natural- and cut-slope stability, spoil-pile stability, ground response to seismic activity, blasting effects, excavatability, bulking characteristics, ground-water conditions, and erosion potential.
Basic hydrologic data available in the field offices of the U. S. Geological Survey and reports issued by the Survey furnish evidence that saline water (defined in this report as water containing more than 1,000 parts per million of dissolved solids) is available under diverse geologic and hydrologic conditions throughout the United States. The number of areas in which undeveloped supplies of fresh water are available has diminished considerably with the rapid growth of industries and population in the past decade. Many areas previously considered to have relatively unlimited water resources have reached the point at which water-supply shortages exist or are threatened.
Red-pigmented biofilms grow on rock and cobble surfaces present in anoxic hot springs located on Paoha Island in Mono Lake. The bacterial community was dominated (∼ 85% of 16S rRNA gene clones) by sequences from the photosynthetic Ectothiorhodospira genus. Scraped biofilm materials incubated under anoxic conditions rapidly oxidized As(III) to As(V) in the light via anoxygenic photosynthesis but could also readily reduce As(V) to As(III) in the dark at comparable rates. Back-labeling experiments with 73 As(V) demonstrated that reduction to 73 As(III) also occurred in the light, thereby illustrating the cooccurrence of these two anaerobic processes as an example of closely coupled arsenotrophy. Oxic biofilms also oxidized As(III) to As(V). Biofilms incubated with [ 14 C]acetate oxidized the radiolabel to 14 CO 2 in the light but not the dark, indicating a capacity for photoheterotrophy but not chemoheterotrophy. Anoxic, dark-incubated samples demonstrated As(V) reduction linked to additions of hydrogen or sulfide but not acetate. Chemoautotrophy linked to As(V) as measured by dark fixation of [ 14 C]bicarbonate into cell material was stimulated by either H 2 or HS − . Functional genes for the arsenate respiratory reductase ( arrA ) and arsenic resistance ( arsB ) were detected in sequenced amplicons of extracted DNA, with about half of the arrA sequences closely related (∼98% translated amino acid identity) to those from the family Ectothiorhodospiraceae . Surprisingly, no authentic PCR products for arsenite oxidase ( aoxB ) were obtained, despite observing aerobic arsenite oxidation activity. Collectively, these results demonstrate close linkages of these arsenic redox processes occurring within these biofilms. Oxyanions of the group 15 element arsenic, arsenate [As(V)] and arsenite [As(III)], have been known for millennia to be potent poisons. Despite its well-established toxicity to life, the phenomenon of arsenic resistance was discovered whereby some microorganisms maintain an otherwise “normal” existence in the presence of high concentrations of As(V) or As(III) (17, 29, 31). More recently it has become recognized that certain representatives from the bacterial and archaeal domains can actually exploit the electrochemical potential of the As(V)/As(III) redox couple (+130 mV) to gain energy for growth. This can be achieved either by employing As(III) as an autotrophic electron donor or by using As(V) as a respiratory electron acceptor (18, 21, 34). The latter phenomenon, although most commonly associated with chemoheterotrophy, can also employ inorganic substances like sulfide or H 2 . Indeed, As(V)-respiring anaerobes displaying a capacity for chemoautotrophy with these electron donors have been isolated and described (5, 7, 16). We recently reported that photoautotrophy is supported by As(III) in anoxic biofilms located in hot springs on Paoha Island in Mono Lake, CA (15). This process represented a novel means of As(III) oxidation achieved via anoxygenic photosynthesis occurring in certain photosynthetic bacteria (i.e., Ectothiorhodospira ) and possibly within some cyanobacteria as well (e.g., “ Oscillatoria ”). Whether or not a microbial habitat is overtly oxic or anoxic, or temporally shifts between these two states over a diel cycle, critical energy linkages between aerobes and anaerobes have long been known for the biogeochemical cycles of key elements, such as sulfur, iron, and nitrogen. Most prominently studied is the case of nitrogen, whereby an ecological coupling exists between the processes of nitrification and denitrification (9, 10, 28). The former process provides energy to aerobic nitrifiers, while the latter process consumes the nitrate produced by this reaction, thereby meeting the energy needs of the denitrifiers. For arsenic, the detection of both As(III) oxidation and As(V) reduction in oxic and anoxic incubations of freshly collected periphyton suggested that an analogous coupled process may also occur for this element (12). Similarly, several uncontaminated soils in Japan displayed a capacity for either As(V) reduction or As(III) oxidation upon arsenic oxyanion amendment and whether they were incubated under oxic or anoxic conditions (39). A defined coculture consisting of an aerobic As(III) oxidizer (strain OL1) and an anaerobic As(V) respirer (strain Y5) was shown to function in this fashion under manipulated laboratory conditions of oxygen tension (26). We pursued the phenomenon of coupled arsenic metabolism further by using materials collected from the hot spring biofilms in Mono Lake, but we focused on examination of the cycling of arsenic under anoxic conditions. In this paper we report results obtained by manipulated incubations of red-pigmented biofilms found in the hot springs of Paoha Island. Preliminary community characterizations of these biofilms show that they are dominated by B acteria from the genus Ectothiorhodospira but also harbor an assemblage of Archaea related to the Halobacteriacaea . Incubation results have demonstrated the presence of the following arsenic metabolic activities: respiratory As(V) reduction, photosynthetic anaerobic As(III) oxidation, and aerobic As(III) oxidation, along with the ecophysiological conditions under which they occur. Surprisingly, we were unable to obtain authentic PCR products for arsenite oxidase genes ( aoxB ), despite observing aerobic As(III) oxidation activity. These biofilms serve as a model system for how anaerobic cycling of arsenic can be sustained with oxidation of As(III) by anoxygenic photosynthesis coupled to regeneration of this electron donor via dissimilatory As(V) reduction. The significance that such a light-driven anaerobic ecosystem may have played in the Archean Earth is discussed.