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Using the All-Sky Monitor (ASM, 1.5–12–kev) data of Rossi X-ray Timing Explorer (RXTE) from January 1996 to May 2005, we have made a detailed analysis of the correlation between photon-count rate and spectral hardness ratio HR2 (5–12 keV/3–5 keV) of the black-hole candidate X-ray binary Cyg X-1 in 3 energy bands, namely the A-band (1.5–3 keV), B-band (3–5 keV) and Cband (5–12 keV). By the study on the ASM data of 1-day time scale, we find: (1) When Cyg X-1 is in the soft state, the A-band photon-count rate and hardness ratio HR2 exhibit an anticorrelation, but in B-band and C-band there appears the positive correlation. When Cyg X-1 is in hard state, the photon-count rates in the A,B,C bands are all inversely correlated with the hardness ratio HR2; (2) No matter whether Cyg X-1 is in the soft state or the hard state, the hardness ratios HR2 and HR1 are always positively correlated. In addition, we have analyzed the “dwell by dwell” data of the ASM, and obtained the following interesting results: (1) In the period of MJD = 52600–52760 (while Cyg X-1 is in the hard state), the photon-count rates in the A-band and B-band are inversely correlated with HR2, but in the C-band there appears a relatively strong positive correlation; (2) During the hard state, a clear anticorrelation exists between the hardness ratios HR2 and HR1. 相似文献
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916.
Chia-Nan Liu Jia-Jyun Dong Yih-Ferng Peng Hsiao-Fung Huang 《Engineering Geology》2009,104(3-4):241-253
Typhoon Herb in 1996 caused widespread debris flows in central Taiwan. The 7.3 Chi-Chi earthquake on September 21, 1999, which also took place in central Taiwan, induced many landslides in the region. These landslides turned into debris flows when Typhoon Toraji struck Taiwan in 2001. This research selects three regions which suffered a ground motion class of 5, 6, and 7 on the Richter scale during the Chi-Chi earthquake as study areas. Air photos from 1997 and 2001 of these regions are used to map the gully-type debris flows that took place after Typhoons Herb and Toraji, respectively. The gullies adjacent to the debris flow, but without a trace of debris flows, are also mapped as the non-debris flow data. The topography, hydrogeology, and rainfall factors – where debris flow occurred and in which there was no occurrence of debris flows in these gullies were retrieved from DTM, geological maps, and iso-countour maps, and of rainfall through GIS processing. These characteristic are introduced into a probabilistic neural network to build a predicting model for the probability of the occurrence of debris flows. Three series of cross analyses are conducted to compare the probability of the occurrence of debris flows of the same dataset predicted by different prediction models. The results reveal that the susceptibility of debris flows was elevated after the Chi-Chi earthquake struck. The upsurge of susceptibility was more obvious for the regions that received a higher class of ground motion. 相似文献
917.
Investigation of fractal distribution law for the trace number of random and grouped fractures in a geological mass 总被引:1,自引:0,他引:1
Yangsheng Zhao Zengchao Feng Weiguo Liang Dong Yang Yaoqin Hu Tianhe Kang 《Engineering Geology》2009,109(3-4):224-229
A fractal study method of the number of geological mass fractures is introduced in detail in this paper. Three main aspects of the problem were studied: (1) The random distribution of fractures in a geological mass was in good agreement with the fractal law. The size scale of the studied geological mass ranged from 2400 m to 1 mm for the length of each side, and the geological mass samples were taken from 13 coal areas in China. (2) The geological mass fractures were evidently directional and anisotropic, having originated from tectonic movement. Observation and statistics for the data from the Xuangang, Fenxi and Dongshan coal areas in Shanxi, China, demonstrated that the fracture distribution of each group, classified by the strike of the strata, still follow the fractal law, even though the fractal dimension varies to a certain extent with different strikes. (3) The sedimentary strata containing the coal seams, as a geological mass, underwent almost similar tectonic movements in their geological history. The mechanical experiments on geological mass samples from Fenxi and Jiexiu in Shanxi demonstrated that the fractal dimension of the number of fractures in the same strata is in good power function with the product of strength and elastic modulus. The larger the product of the strength of the elastic modulus is, the larger is the fractal dimension, and vice versa. 相似文献
918.
鄂尔多斯盆地长9油层组石油运聚规律研究 总被引:11,自引:0,他引:11
鄂尔多斯盆地长9油层组是一个新发现的含油层。迄今为止,有关长9油层组石油运聚成藏机理尚不清楚,特别是对石油运聚规律缺乏认识。该问题的解决会进一步完善鄂尔多斯盆地中生界延长组石油成藏理论;同时,对长9油层组石油勘探开发具有重要的指导作用。我们对长9油层组石油来源、油气输导体系、油气运移路径和油气运移动力等油气运聚条件特征及其不同地区差异进行了研究,结果表明,长9油层组原油主要来自长7烃源岩,只有在志丹局部地区来自长7和长9烃源岩;长9油层组石油的纵向运移路径是由上向下运移;孔隙型输导体和断层、构造裂隙输导体是长9油层组石油运移的主要输导体;盆地长7油层组普遍存在高过剩压力带,长7与长9油层组之间存在较大的流体压力差,因此长7油层组生成的油气在高过剩压力驱动下可以向下运移,进入储层物性相对好的长9砂体聚集成藏。同时,建立了3种长9油层组油气运聚模式,讨论了长9油层组油气运聚机理 相似文献
919.
Shuguang Li Chenxiang Wang Feng Dong Zhenhui Hou Qiuli Li Yican Liu Fang Huang Fukun Chen 《Tectonophysics》2009,475(2):308-317
In order to understand the vertical structure of the Dabie–Sulu ultrahigh-pressure metamorphic (UHPM) belt, common Pb isotopic compositions of omphacites in eclogites and feldspars in gneisses from the Chinese Continental Scientific Drilling (CCSD) project (100–5000 m) have been investigated in this study. Samples from 0 to 800 m (unit 1) in the drilling core have moderately high radiogenic Pb isotopes with small variations of 206Pb/204Pb (16.82–17.38), 207Pb/204Pb (15.37–15.49), and 208Pb/204Pb (37.21–37.72), indicating either high µ (238U/204Pb) or high initial Pb isotope ratios of their protoliths. In contrast, the samples from 1600 to 2040 m (unit 3) and most of samples from 3200 to 5000 m (unit 5) have moderately or very unradiogenic Pb (unit 3: 206Pb/204Pb from 16.05 to 16.46, 207Pb/204Pb from 15.22 to 15.29, and 208Pb/204Pb from 36.68 to 37.48; unit 5: 206Pb/204Pb from 15.52 to 15.69, 207Pb/204Pb from 15.15 to 15.27, and 208Pb/204Pb from 36.48 to 37.20), indicating either low µ or low initial Pb isotope ratios of their protoliths. Pb isotopes of samples from 800 to 1600 m (unit 2) and from 2040 to 3200 m (unit 4) in the drilling core with abundant ductile shear zones are intermediate between those of units 1 and 3 or 5 and display larger variations. Pb isotopes combined with the published oxygen isotope data of the CCSD samples reveal the original positions of the five units before the Triassic continental subduction. Units 1, 3, and 5 as three UHPM rock slabs could be derived from the subducted upper continental crust, upper–middle continental crust and lower–middle continental crust, respectively. The ductile shearing zones in units 2 and 4 could be the interfaces where the detachment and decoupling took place between the upper, upper–middle and lower–middle continental crusts. The detachment between the upper slab and subducting continental lithosphere probably occurred during continental subduction, and the upper slab (unit 1) was uplifted to a shallow depth along the detachment surface by thrusting. Units 3 and 5 may be detached later from the subducted middle and lower crust and uplifted to a shallow level underneath unit 1. The low δ18O values (? 4.0 to ? 7.4‰) [Xiao, Y.-L., Zhang, Z.-M., Hoefs, J., Kerkhof, A., 2006. Ultrahigh-pressure Metamorphic Rocks from the Chinese Continental Drilling Project-II Oxygen Isotope and Fluid Inclusion Distributions through Vertical Sections. Contribution Mineral Petrology 152, 443–458.; Zhang, Z.-M., Xiao, Y.-L., Zhao, X.-D., Shi, C., 2006. Fluid-rock interaction during the continental deep subduction: oxygen isotopic profile of the main hole of the CCSD project. Acta Petrologica Sinica 22 (7), 1941–1951.] in units 2 and 4 suggest that the detachment interfaces could be developed along an ancient fault zones which were the channels of meteoric water activity during the Neoproterozoic. 相似文献
920.