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421.
Introduction The Tanlu fault zone, the largest active structure in the eastern region of China, is character-ized by right lateral strike-slip movement with dip-slip component in the Quaternary; it shows great significance for the modern seismicity (FANG et al, 1976; Institute of Geophysics, China Earthquake Administration, 1987; GAO et al, 1980; MA, 1987; LI, 1989; CHAO et al, 1995). The Tanlu fault zone is the boundary between the Jiaoliao block and the North China Plain block of … 相似文献
422.
空间决策支持系统在商业智能中的应用研究 总被引:1,自引:0,他引:1
介绍了空间决策支持系统和商业智能的基本概念。分析了对商业决策有影响的空间因素,并借鉴Huff模型对网点吸引力进行了表达。描述了商业空间决策支持系统的总体设计。 相似文献
423.
利用Poisson积分推导Hotine函数及Hotine公式应用问题 总被引:2,自引:0,他引:2
给出一种直接利用改进的Poisson积分确定Hotine函数的推导 ,其中不包括函数的零阶和一阶项。讨论了Hotine公式在陆地和海洋局部重力场逼近中的应用问题。 相似文献
424.
关于我国似大地水准面的精化及有关问题 总被引:11,自引:0,他引:11
晁定波 《武汉大学学报(信息科学版)》2003,(Z1)
着重分析了我国新一代似大地水准面模型CQG2 0 0 0的实际分辨率 ,给出了该模型的精度估计 ,得出总体分辨率为 2 0km ,精度为± 0 .4m ;60 %地区分辨率达到或优于 1 0km ,精度为± 0 .3m。介绍了目前精化大地水准面的国际先进水平 ,指出了进一步精化我国大地水准面的必要性和途径及有关问题。 相似文献
425.
426.
讨论了相对论意义下的重力位及大地水准面,指出了等时率大地水准面的缺陷,建议今后采用等频面及等频大地水准面的概念,给出了等频大地水准面与经典大地水准面的差异,同时给出了等频大地水准面的近似表达式。 相似文献
427.
Most of petroliferous sedimentary basins in China have experienced multiple phases of tectonic evolution and deposition, and are characterized by tectonic and depositional superimposition. The term "superimposed basin" is suggested to describe those basins which consist of two or more simple prototype basins superimposing vertically and/or coalescing laterally. The characteristics of petroliferous superimposed basins are "multiple stages of basin forming and reworking, multiple layers of source rocks, multiple periods of hydrocarbon generation and expulsion, multiple periods of petroleum migration-accumulation-escape". Therefore,applying the wave process analysis method to studying the process of basin formation, hydrocarbon generation, and reservoir formation, and then establishing theory of "petroleum accumulation system" is helpful to enhancing petroleum exploration efficiency in superimposed basins.This paper will, based on case study in the Tarim basin, report the major developments in studying basin formation, hydrocarbon generation and petroleum accumulation. In study of basin formation, (1) geophysical comprehensive profiles reveal that the Tarim plate has been subducted beneath the Tianshan orogenic belt with an interfinger structure and that the deep structure in the eastern section of the Tianshan orogenic belt is different from that in the western section. (2) The vertical variation in debris and geochemical composition reveals the nature and Mesozoic-Cenozoic evolution history of the Kuqa Depression. (3) Field investigation and paleostress reconstruction show that the Kuqa Depression has undergone gravity-driven extension in sedimentary cover when the Tianshan uplifted vertically. In hydrocarbon generation study, new developments include (1) setting environmental index to judge high grade source rocks in marine carbonates, and (2) establishing the lower limit of the organic carbon content for effective carbonate source rocks. In petroleum accumulation study, (1) methods of determining paleopressure and paleotemperature of forming fluid inclusions have been established. (2) The petroleum source analysis has indicated that the crude oil in the Lunnan and Tahe oilfields are derived from the source rocks of the Middle and Upper Ordovician. (3) Three generations of oil inclusions from the Lunnan oilfield have been recognized and dated. 相似文献
428.
We use the Pg seismic phase along the Korla-Jimsar profile across the Tianshan orogen and the 3D finite difference method to inverse the velocity structure of the upper crust beneath the basement of this mountain. Based on the velocity structure, the Korla-Jimsar profile can be divided into three parts, i.e. the north edge of the Tarim basin, the Tianshan orogen, and the south margin of the Junggar basin. Within the Tianshan there is a pattern of four convexities and three concavities, which correspond to the southern Tianshan, the Yanqi basin, the middle Tianshan, the Turpan basin, and the Bogda Mountains. In the north edge of the Tarim basin, the basement is about 10km deep with small lateral variations of velocity. In the Tianshan the velocity varies greatly laterally. The basement depth of the Yanqi basin is 6 km, which becomes shallow rapidly northward, and almost to the surface at the middle Tianshan. South to Kumux there is a small intermountain basin, where the maximum basement depth is 3 km, and also turns very shallow near Kumux. The Luntai fault, which bounds the Tarim basin and Tianshan, has vertical dislocation of about 5 km. The Turpan basin is covered with so thick a sediment that its basement is 7 km deep. The boundary fault between the Tianshan and Turpan is the Bolohoro fault which is characterized by quick deepening basement and 7 km vertical dislocation. In the Junggar basin the basement is 8 km deep. On the Korla-Jimsar profile, the velocity distribution of the upper crust and the structure are featured by NS symmetry on both sides of the axis of the Middle Tianshan, consistent with the deep structure revealed by this profile. It means that the Tarim basin and the Junggar basin underthrust toward the Tianshan from south and north, respectively. Such a structural style is different from that of another profile, i.e. the Xayar-Burjing profile, suggesting that there may be an important tectonic boundary between these two profiles. 相似文献
429.
利用由多代卫星测高资料反演得到的 2 .5′× 2 .5′空间重力异常数据 ,解释了南海地块边界及内部结构的重力异常特征 ,表明高分辨率的重力异常资料有助于研究海洋岩石圈的细结构和资源评估勘探 相似文献
430.