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961.
962.
江西煤田地质勘探的形势是严峻的,后备煤炭资源严重不足。无可供建井设计利用的精查储量,无可供精查的详查储量,可供详查的普查储量少,可供普查的找煤储量更少。地质勘探的找煤、普查与详查比例严重失调,许多矿井又面临资源枯竭、按替困难的局面。江西仍有较多的煤田勘探靶区需要勘探验证,煤炭工业有广阔的市场。希望政府采取各种措施加大对煤田地质勘探的投入。 相似文献
963.
层序地层与煤层气关系探讨 总被引:2,自引:0,他引:2
从层序地层的角度,对煤层气的生、储和保存进行了论述,试图找出层序地层与煤层气之间的联系,并对体系域与煤层气之间的关系作了探讨。 相似文献
964.
新疆煤炭资源勘查开发现状与可持续发展 总被引:1,自引:0,他引:1
新疆煤炭资源分布极不均衡。煤炭资源预测量虽然居全国首位,但是探明程度却很低。进行西部大开发,有计划地加强缺煤地区的煤炭资源勘查,合理规划开发,调整煤炭生产结构,实现资源转换战略。在保护生态环境,防止沙漠化漫延的同时,提高当地人民生活水平。 相似文献
965.
966.
应用时空变—倾角扫描叠加KL变换提高地震资料信噪比 总被引:3,自引:0,他引:3
使用KL变换可去除地震资料中随机噪声和相干噪声,提高地震资料信噪比。但常规KL变换仅能加强水平方向同相轴,对倾斜或弯曲同相轴处理效果较差,且在处理大量数据时计算成本很高,在实际生产中难以广泛应用。一些文献中针对常规KL变换的两个缺陷进行了改进,即使用倾角扫描叠加KL变换和采用数据分块技术。作者在本文中将这两个方面的改进有机地结合起来,提出应用时空变-倾角扫描叠加KL变换对地震资料进行处理,并指出使用该方法时需要注意的一些问题。理论模型和实际资料处理效果表明,使用本方法可以克服常规KL变换的缺陷,有效改进剖面处理效果。 相似文献
967.
A nearly 100-km-long surface rupture zone, called Chelungpu surface rupture zone, occurred mostly along the pre-existing Chelungpu fault on the northwestern side of Taiwan, accompanying the 1999 Chi-Chi Ms 7.6 earthquake. The Chelungpu surface rupture zone can be divided into four segments based on the characteristics of co-seismic displacements, geometry of the surface ruptures and geological structures. These segments generally show a right-step en echelon form and strike NE–SW to N–S, and dip to the east with angles ranging from 50 to 85°. The co-seismic flexural-slip folding structures commonly occurred in or near the surface rupture zone from a few meters to a few hundreds of meters in width, which have an orientation in fold axes parallel or oblique to the surface rupture zone. The displacements measured in the southern three segments are approximately 1.0–3.0 m horizontally and 2.0–4.0 m vertically. The largest displacements were measured in the northern segment, 11.1 m horizontally and 7.5 m vertically, respectively. The amount of co-seismic horizontal shortening caused by flexural-slip folding and reverse faulting in the surface rupture zone is generally less than 3 m. It is evident that the co-seismic displacements of the surface rupture zone are a quantitative surface indicator of the faulting process in the earthquake source fault. The relations between the geometry and geomorphology of the surface rupture zone, dips of the co-seismic faulting planes and the striations on the main fault planes generated during the co-seismic displacement, show that the Chelungpu surface rupture zone is a reverse fault zone with a large left-lateral component. 相似文献
968.
David C. Oyler Christopher Mark Dennis R. Dolinar Russell C. Frith 《Geotechnical and Geological Engineering》2001,19(2):137-168
Unusual circumstances may require that a longwall retreat into or through a previously driven room. The operation can be completed successfully, but there have been a number of spectacular failures. To help determine what factors contribute to such failures, a comprehensive international database of 131 case histories has been compiled. The cases include six failures where major rock falls occurred in front of the shields, and seven even more serious failures involving major overburden weighting. The case studies suggest two types of room failure mechanism. The first is a roof fall type failure caused by loading of the immediate roof at the face as the fender or remnant longwall panel narrows. The second is an overburden weighting type failure caused by the inability of the roof to bridge the recovery room and face area, and affecting rock well above the immediate roof. The data indicate that the roof fall type of failure is less likely when intensive roof reinforcement (bolts, cables and trusses) is employed together with higher-capacity shields. The overburden weighting failures, in contrast, occurred when the roof was weak and little standing support was used. Weighting failures were not greatly affected by the density of roof reinforcement. In one of the overburden weighting cases, in a Pittsburgh coalbed mine, stress cell, convergence, bolt load and extensometer data have been used to analyze the failure in detail. 相似文献
969.
Ludmila A. Pavlova Ludmila Ph. Paradina Olga Yu. Belozerova 《Geostandards and Geoanalytical Research》2001,25(2-3):333-344
In this paper we report the results of electron probe X-ray microanalysis (EPMA) that was used to study environmental materials. The mode of preparation and certification of reference samples based on a basaltic glass matrix for environmental applications of EPMA is described. These samples were prepared containing scandium, strontium and barium (from 0.03 up to 7% m/m) and an evaluation was made of homogeneity, their stability to local heating, followed by analysis by independent methods for certification of composition. Matrix correction procedures for the EPMA technique have been developed for particles having a size commensurable with the volume of X-ray generation. An analytical equation for the size factor is proposed and two techniques for selecting optimum conditions for the analysis of environmental samples by EPMA are reported. These procedures provided satisfactory results when utilized in analysing sediments recovered from snow, coal fly ash and the bones of animals and fish, results from which can be used as indicators for evaluating the pollution level of the lower atmosphere, surface and ground water, as well as revealing pollution mechanisms. 相似文献
970.
A. Alastuey A. Jimnez F. Plana X. Querol I. Surez-Ruiz 《International Journal of Coal Geology》2001,45(4)
This study is focused on the occurrence and distribution of mineral matter and major and trace elements in the high volatile bituminous coal from Puertollano (south-central Spain). The relationship between ash behaviour and inorganic composition, as well as the possible formation of fouling and slagging deposits in boilers during the conversion process, were investigated. The Puertollano coals do not exhibit plastic properties, despite their rank, probably because of their high ash and inertinite contents.The Puertollano coal has medium to low total S content (0.48% to 1.63% db, with a mean of 1.0% db) and is characterised by relatively high contents of Si, Pb, Sb, and Cs. Some elements such as As, Cd, Co, Cr, Cu, Ge, Li, Mn, Ni, W, and Zn are also present in relatively high contents. The enrichment in a number of heavy metals could be attributed to the common sulphide ores occurring near the Puertollano coal deposit.The following trace elements affinities are deduced: (a) sulphide affinity: As, Co, Cd, Cu, Ni, Sb, Tl, and Zn; (b) aluminum–silicate affinity: K, Ti, B, Co, Cr, Cs, Cu Ga, Hf, Li, Nb, Rb, Sn, Ta, Th, V, Zr, and LREE; (c) Carbonate affinity: Ca, Mg, Mn, and B; (d) organic affinity: B.The very high Si levels and the anomalous enrichment in Cs, Ge, Pb, Sb, and Zn shown by the Puertollano coals account for the high contents of these elements in the Puertollano fly ash when compared with the other Spanish coal fly ashes.The chemical composition of the high temperature ash (HTA) is consistent with the trend shown by the ash fusion temperatures (AFT) and also with the predictive indices related to slagging and fouling propensities. Thus, the ash fusion temperatures increase with high values of Al2O3 as well as with the decrease in Fe2O3, CaO, and MgO. 相似文献