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21.
大泉水-白沙岘矿区位于甘肃省景泰县境内,在大地构造位置上处于北祁连加里东褶皱带东段,区内含煤地层为下石炭统靖远组和上石炭统羊虎沟组,属海陆交互相含煤沉积,根据岩性、岩相特征可划分为两个沉积旋回。该矿区主要可采煤层煤.层组赋存于羊虎沟组,厚1.71~9.00m,沿走向由西向东厚度变小,在大泉水井田可采厚度主要分布在V线以西,其东区段只是零星分布且不可采;在白沙岘井田煤层总厚度为2.99~5.15m,厚度变化小,属稳定煤层。煤:层组赋存于靖远组,仅分布在大泉水井田,厚1.33~8.88m,沿走向由西向东呈长透镜体状,西段和中段煤层发育较好.V线以东区段煤层变薄并出现无煤区。 相似文献
22.
G. N. Tsokas G. C. Christofides C. Papakonstantinou 《Pure and Applied Geophysics》1996,146(2):365-392
Intrusive features of varying size can be interpreted from the aeromagnetic map of the Xanthi area in N. Greece.The Xanthi pluton, which outcrops north of the city of Xanthi, seems to have the shape of a truncated pyramid. This feature has relatively large areal extent and reaches an approximate depth of 7 km. Another, relatively large magnetic body is buried under the sediments at the estuary of the Nestos River.3-D models of several smaller intrusions were constructed and the produced effect was compared to the observed. Some of these intrusions seem to be detached branches of the large Xanthi pluton.The basement in the outer part of the basin of the Nestos River seems to be buried at about 4 km depth. This figure is obtained by the Multiple Source Werner Deconvolution estimates and it is in agreement with the results of former geophysical studies and deep industrial boreholes.A 3-D model of the Xanthi-Komotini basin suggests that this basin is about 0.4 km deep at its southern part. The depth at its northern boundary is about 1.8 km while the boundary itself is formed by the large Kavala-Xanthi-Komotini fault.The Tertiary basin of the Nestos River and the observed magmatism are consistent with the idea of an older extensional tectonic regime in the area. 相似文献
23.
Early Cretaceous sandstones and shales from the Thakkhola region (Chukh and Tangbe Formations) were deposited on the subsiding northern (Tethyan) margin of Gondwana; current directions indicate a source area to the south. Whereas the Berriasian Chukh Formation is dominated by quartz arenites, volcaniclastic sandstones and minor conglomerates dominate the Tangbe Formation of Valanginian to Aptian age. Upsection, the composition of the volcaniclastic components changes from mainly basaltic to dominantly dacitic/rhyolitic. Magmatism was preceded and accompanied by strong uplift in the source area of the Chukh and Tangbe clastics, resulting in the erosion of probably more than several hundred meters of pre-Cretaceous sedimentary, metamorphic and plutonic rocks. A geochemical whole rock analysis of basaltic pebble fragments shows their alkaline character and suggests a within-plate geotectonic setting for the volcanic source. This volcanotectonic event is probably related to rifting between Australia and Greater India, where seafloor spreading began in late Valanginian/Hauterivian times. 相似文献
24.
在人体胃肠液的酸度条件下,采用正辛醇-水分配体系模拟药物在人体肠胃中的分配情况,研究了中药和补铁制剂中铁的形态及其在人体内的吸收情况,并探讨了中药不同比例的配伍、胃肠酸度及还原性物质的存在对水溶态铁和醇溶态铁的影响。结果表明,药物溶液中的铁形态与药物本身特性和配伍情况有关,酸度及配伍对药物中铁的溶出率和溶液中铁的形态有较大影响,人体对铁的吸收与胃肠酸度和还原性物质的存在有关。 相似文献
25.
随着空间科学技术和计算机技术的发展,以“3S”技术为代表的测绘高新技术已普遍应用于测绘生产中。作为培养测绘实用型人才的测绘职业学校,测绘专业如何重新划分、测绘教育与教学内容如何改革,是测绘教育界普遍关注的问题,本文从教学的角度对有关问题进行了探讨。 相似文献
26.
G. M. da Costa E. Van San E. De Grave R. E. Vandenberghe V. Barrón L. Datas 《Physics and Chemistry of Minerals》2002,29(2):122-131
A novel method for synthesis of aluminium hematites, based upon the homogeneous precipitation of Fe and Al oxinates in various proportions, is presented. The precursor precipitates are heated in air at 700?°C. X-ray diffraction, thermal analyses, BET, FTIR, optical reflection analysis, TEM and Mössbauer spectroscopy at room temperature and 80?K of the resulting products indicate that single-phase hematites are formed with structural Al substitution of up to 10 at%. Interestingly, the particle size (>100?nm) is not substantially reduced by the Al content. Although it remains difficult to obtain a homogeneously distributed Al substitution in the final hematite, this processing line offers a unique opportunity to separate the effects of grain size and Al substitution on the Morin transition temperature (T M) of Al hematite. From the comparison between the present hematites and a series of Al-substituted hematites with lepidocrocite as precursor, it could be shown that the effect on T M, associated with a change of a factor 10 in grain size, is about 1/3 of the effect caused by a change of 10 in the degree of substitution. Finally, it is suggested that proper thermal treatments under different conditions of the same precursors are likely to produce spinel phases. 相似文献
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29.
通过月整点值数据文件和滑动值数据文件这两种数据处理形式。对九江台地倾斜资料进行调和分析计算。分析了M2潮汐因子与瑞昌ML4.9级地震的关系。认为存在震前短临异常或震后异常,并与趋势异常得到相互印证。 相似文献
30.
Introduction According to the determination of the state seismic station network, a strong earthquake with magnitude of 6.0 occurred at 08h09min, February 23, 2001 (Beijing Time) in the mountainous area of Garze, Sichuan Province in southwest China. The epicenter is at 101?6E, 29?4N. The seismic region is just located on combining part among six counties. After the occurrence of the earthquake, an investigating team from the Seismological Bureau of Sichuan Province started off to the sei… 相似文献