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[en] Here we detail the new data acquisition system (DAS) developed for the CSIRO Nuclear Microprobe primarily to handle large detector arrays and to work in tandem with the Maia detector system. Both systems use HYMOD FPGA-based processors. The current DAQ system and its microscopy suite and beam handling have been integrated with the HYMOD system(s) to facilitate easy access to the either system. Examples of the new scanning modes available with the combined system are highlighted on a complex Cambrian black shale sample from the Yangtze basin in Southern China.
[en] Mercury enrichments in the black shale unit of the Ediacaran Doushantuo Formation are, likely the result of volcanic input or anoxia-driven mercury deposition. If the Hg enrichments are volcanic in origin, or are due to synchronous regional anoxia, then the patterns of Hg enrichment are consistent with the conventional correlation of these units, with the tripartite units equivalent to Member IV black shales. Additionally comparing redox proxy data from the intervals of Hg enrichment could indicate if the enrichments are due to comparable changes in redox conditions, or increased Hg input under differing redox conditions, consistent with volcanic input.
[es]Los enriquecimientos de mercurio en la unidad de esquisto negro de la Formación ediacárica de Doushantuo son probablemente el resultado de la influencia volcánica o del depósito de mercurio mediante anoxia. Si los enriquecimientos de Hg son de origen volcánico, o se deben a una anoxia regional contemporánea, entonces los patrones de enriquecimiento de Hg son consistentes con la correlación convencional de estas unidades, con las unidades tripartitas equivalentes a la pizarra negra del Miembro IV. Además, la comparación de los datos redox de los intervalos de enriquecimiento en Hg podría indicar si los enriquecimientos se deben a cambios comparables en las condiciones redox, o a un aumento de la entrada de Hg bajo diferentes condiciones redox, consistente con la influencia volcánica.
[en] The distribution of fractured organic shale basins in the United States was discussed. More than 20,000 gas shale wells have been drilled in the Appalachian Basin which produce about 960 MMscf/D from fractured organic shales. The key features of organic-rich shale reservoirs were described. These reservoirs contain significant amounts of gas in place, as well as sorbed gas in the black organic shale matrix. When natural fractures are present in these formations, such as in the Antrim Shale in northern Michigan, there exists significant production potential. A review of the production history of the Antrim Shale was provided. The storage and production techniques which determine the performance of these formations were described and the procedures to evaluate the techniques were summarized. The impact of technology and development on the production of the Antrim Shale was also reviewed. Evaluation of these shale resources is made through the estimation of reserves by analyzing short-term and long-term production data. Reservoir pressure and effective bottom hole flowing pressure can also be used to evaluate the reserves. tabs., figs
[en] During fiscal year 1993, the reserves generated $440 million in revenues, a $33 million decrease from the fiscal year 1992 revenues, primarily due to significant decreases in oil and natural gas prices. Total costs were $207 million, resulting in net cash flow of $233 million, compared with $273 million in fiscal year 1992. From 1976 through fiscal year 1993, the Naval Petroleum and Oil Shale Reserves generated $15.7 billion in revenues for the US Treasury, with expenses of $2.9 billion. The net revenues of $12.8 billion represent a return on costs of 441 percent. See figures 2, 3, and 4. In fiscal year 1993, production at the Naval Petroleum and Oil Shale Reserves at maximum efficient rates yielded 25 million barrels of crude oil, 123 billion cubic feet of natural gas, and 158 million gallons of natural gas liquids. The Naval Petroleum and Oil Shale Reserves has embarked on an effort to identify additional hydrocarbon resources on the reserves for future production. In 1993, in cooperation with the US Geological Survey, the Department initiated a project to assess the oil and gas potential of the program's oil shale reserves, which remain largely unexplored. These reserves, which total a land area of more than 145,000 acres and are located in Colorado and Utah, are favorably situated in oil and gas producing regions and are likely to contain significant hydrocarbon deposits. Alternatively the producing assets may be sold or leased if that will produce the most value. This task will continue through the first quarter of fiscal year 1994
[en] The thermal maturity of shale is often measured by vitrinite reflectance (VRo). VRo measurements for the Devonian–Mississippian black shale source rocks evaluated herein predicted thermal immaturity in areas where associated reservoir rocks are oil-producing. This limitation of the VRo method led to the current evaluation of Raman spectroscopy as a suitable alternative for developing correlations between thermal maturity and Raman spectra. In this study, Raman spectra of Devonian–Mississippian black shale source rocks were regressed against measured VRo or sample-depth. Attempts were made to develop quantitative correlations of thermal maturity. Using sample-depth as a proxy for thermal maturity is not without limitations as thermal maturity as a function of depth depends on thermal gradient, which can vary through time, subsidence rate, uplift, lack of uplift, and faulting. Correlations between Raman data and vitrinite reflectance or sample-depth were quantified by peak-fitting the spectra. Various peak-fitting procedures were evaluated to determine the effects of the number of peaks and maximum peak widths on correlations between spectral metrics and thermal maturity. Correlations between D-frequency, G-band full width at half maximum (FWHM), and band separation between the G- and D-peaks and thermal maturity provided some degree of linearity throughout most peak-fitting assessments; however, these correlations and those calculated from the G-frequency, D/G FWHM ratio, and D/G peak area ratio also revealed a strong dependence on peak-fitting processes. This dependency on spectral analysis techniques raises questions about the validity of peak-fitting, particularly given the amount of subjective analyst involvement necessary to reconstruct spectra. This research shows how user interpretation and extrapolation affected the comparability of different samples, the accuracy of generated trends, and therefore, the potential of the Raman spectral method to become an industry benchmark as a thermal maturity probe. A Raman method devoid of extensive operator interaction and data manipulation is quintessential for creating a standard method.
[en] During fiscal year 1992, the reserves generated $473 million in revenues, a $181 million decrease from the fiscal year 1991 revenues, primarily due to significant decreases in oil and natural gas prices. Total costs were $200 million, resulting in net cash flow of $273 million, compared with $454 million in fiscal year 1991. From 1976 through fiscal year 1992, the Naval Petroleum and Oil Shale Reserves generated more than $15 billion in revenues and a net operating income after costs of $12.5 billion. In fiscal year 1992, production at the Naval Petroleum Reserves at maximum efficient rates yielded 26 million barrels of crude oil, 119 billion cubic feet of natural gas, and 164 million gallons of natural gas liquids. From April to November 1992, senior managers from the Naval Petroleum and Oil Shale Reserves held a series of three workshops in Boulder, Colorado, in order to build a comprehensive Strategic Plan as required by Secretary of Energy Notice 25A-91. Other highlights are presented for the following: Naval Petroleum Reserve No. 1--production achievements, crude oil shipments to the strategic petroleum reserve, horizontal drilling, shallow oil zone gas injection project, environment and safety, and vanpool program; Naval Petroleum Reserve No. 2--new management and operating contractor and exploration drilling; Naval Petroleum Reserve No. 3--steamflood; Naval Oil Shale Reserves--protection program; and Tiger Team environmental assessment of the Naval Petroleum and Oil Shale Reserves in Colorado, Utah, and Wyoming
[en] After the end of World War II, in 1945 prospecting for uranium in north-eastern Estonia was carried out and the production of uranium concentrate was charged with by the Soviet Government and organized by the USSR Ministry of the Middle Engineering Industry at Sillamaee. The data about this production, technology and wastes were kept secret. It was only April 1992 when official information on this area was received from the Ministry of Atomic Energy for the first time addressed to Chairman of the Estonian Supreme Soviet. The following measures have been suggested with respect to the environmental protection at Sillamae:1. to evaluate and re cultivate 100 ha of radioactively polluted area; 2. to build a storage for disposing waste; 3. to liquidate the radioactive and toxic wastes mixed with ash stockpiled on an area of 40 ha; 4. to carry out deactivation of former, radioactively polluted metal storages on an area of 20 ha. As no financial support for this project will be received from Moscow, the Swedish Government has offered to help in solving the environmental problems related to the Sillamaee Plant. Herewith we publish the report of M. Althausen, one of the leading Russian geologists, on Estonian uraniferous dictyonema shales
[en] The accuracy of the results of analysis by inductively coupled plasma mass spectrometry (ICP-MS) was studied for the deetermination of rare-earth elements in black shales rich with carbonaceous organic substance of different nature: biogenic (samples SChS-1 and Slg-1, which were put through benchmark tested in Institute of Geochemistry, Siberian Division, Russian Academy of Sciences) and bituminous (SDO-1 and SGR-1, reference samples of US Geological Survey). Based on the comparison of the results obtained by the ICP-MS method with the reference data for SChS-1 and Slg-1 shales, it is found that the systematic error depends on the technique of samples decomposition: in open systems (A), in autoclaves (B), and by fusion with lithium metaborate (N). It is demonstrated that the use of method C provides the smallest deviations between the obtained and reference concentrations. The bahavior of rare-earth elements in the analysis of SDO-1 and SGR-1 shales differs from their behavior in the analysis of SChS-1 and Slg-1: systematic errors were not revealed when the above decomposition methods were used
[ru]Исследована правильность результатов анализа при масс-спектрометрическом с индуктивно связанной плазмой (ИСП-МС) определении редкоземельных элементов (РЗЭ) в черных сланцах, богатых органическим углеродистым веществом различного происхождения: биогенного (образцы СЧС-1 и СЛг-1, проходящие аттестационные исследования в Институте геохимии СО РАН) и битуминозного (SDO-1 и SGR-1, стандартные образцы геологической службы США). На основании сравнения результатов, полученных методом ИСП-МС, с контрольными данными для сланцев СЧС-1 и СЛг-1 выявлена зависимость систематической погрешности от способа вскрытия проб: в открытых системах (А), в автоклавах (В) и при сплавлении с метаборатом лития (С). Показано, что при использовании С метода наблюдаются наименьшие расхождения между полученными и контрольными содержаниями. Поведение РЗЭ при анализе сланцев SDO-1 и SGR-1 отличается от поведения при анализе СЧС-1 и СЛг-1: систематические погрешности не были выявлены при используемых способах разложения
[en] During the field work for profile observation of Qingxi Formation, Lower Cambrian in Wujia, Ziyuan county, northern Guangxi and Mupikou, Quanzhou City the authors discovered in the previously-identified 'Siltstone' and 'ballistic feldspar-quartz sandstone' of the Qingxi Formation, a lot of tuffaceous fragments (crystalloclastic fragments). Later 2-3 horizons of tuffite with different thickness were found in uranium-rich black shale series of the same age in Longshen and Rongshui counties, northern Guangxi, in Chengbu, Wugang and Xingnin counties, Southwestern Hunan. Based on chemical composition, texture features of the rocks and various variation diagrams it is certain that these rocks are tuffite which have turned into metamorphic sedimentary tuffite after the diagenesis and epi metamorphic process
[en] The organic-rich Macasty shale in the Gulf of St. Lawrence was deposited in the Late Ordovician during the Taconic orogeny. The orogeny involved explosive volcanism and thrusting of allochthonous rocks in the eastern margin of North America. Neodymium isotope compositions of the shale show that the provenance is predominantly Grenvillian granite- gneissic rocks, which were widely exposed north of the basin, with little contribution from Taconic igneous rocks. The bulk composition and the presence of detrital kaolinite suggest that the Grenvillian source rocks underwent intense weathering before erosion. Fine-grained detritus was deposited in the Anticosti Basin, where abundant organic activity kept the sediment- water interface under anoxic conditions. This proposed interpretation is supported by the enrichment of redox-sensitive elements, such as As, V, and U, and by high δ34S for pyrite. Calcite cement formed in the pore space of sediments during the diagenesis at temperatures below 60 °C. The low-temperature diagenetic conditions are consistent with the preservation of abundant organic matter in the shale. (author)