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241.
准噶尔盆地南缘东段油气成藏条件及成藏模式 总被引:1,自引:1,他引:0
准噶尔盆地南缘东段是准噶尔盆地油气勘探的重点地区。以成盆、成烃和成藏理论为指导,应用盆地分析、有效烃源岩评价、储层(裂缝)预测、盆地模拟及流体包裹体分析等技术和方法,综合研究分析了准噶尔盆地南缘东段油气成藏条件,预测了油气资源潜力,建立了油气成藏模式。研究结果表明,该区发育上二叠统、中上三叠统和中下侏罗统三套烃源岩。最主要的烃源岩层为上二叠统,是油气资源分布的主要层位;主要储集层为柴窝堡区块的上二叠统和米泉区块的中下三叠统及中下侏罗统,其物性较差,总体为较好含气储层,是主要的勘探目的层。存在自源(侧向排烃)、它源(垂向排烃)两类油气成藏模式。柴窝堡区块北部和米泉区块仍然是有利的油气勘探地区。 相似文献
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通过地幔粘滞性及粘滞结构、地幔热状态、地幔热生成三个方面,探讨了地幔物质发生对流的物理背景,并归纳出地幔对流模式热动力系统,在此基础上剖柏了地幔对流和现代板块构造的直接联系。 相似文献
244.
Luo Zhaohua Xiao Xuchang Cao Yongqing Mo Xuanxue Su Shangguo Deng Jinfu Zhang Wenhui 《中国科学D辑(英文版)》2001,44(1):10-17
Geodynamic properties and evolution of the lithosphere on the north margin of the Tibetan Plateau are recently hot topics to geoscientists in the world. Have the northern plates been subducting underneath the Plateau? It is still an unsolved problem. One of the keys to solving this problem is to understand the genetic processes of Cenozoic magmas on the north margin of the Tibetan Plateau. However, there is no enough evidence supporting the subduction model. In contrast, a series of evidence indicates that collision-induced huge shearing faults and large-scale crust shortening played a main role in lithosphere motion on the north margin of the Tibetan Plateau. The mantle-derived igneous rocks strictly distribute at the intersections of large strike-slip faults on the north margin of the Plateau. Generation of magmas may be related to local extensional condition induced by strike-slipping faults, which lead to lithosphere gravitational instability and collapse, as well as upwelling of the deep hot material. Heat induced by shearing and carried by upwelling hot material may cause partial melting on H2O-bearing mantle. 相似文献
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ZhangZhenfei HuGuangdao YangMingguo LiuXing WangZhenlmi LiWenhui ZhangXiaobing HeLi 《中国地质大学学报(英文版)》2003,14(3):257-260
Field data of outcrop spectrums provide important basis for modeling of hyper-spectral remote sensing aiming at mineral prospecting. We make an approach to the application of rough set theory in spectral discriminiation of rocks. We build a decision table with an adequate number of samples (out-crops) of known rock type (the universe), of which the conditional atributes are discretized “area spectrum absorption indexes“ (ASAI) corresponding to wavelength intervals, and the decision atribute is rock type. We search to obtain the exhaustive set of reducts of the table, each of which will serve as a variable number of deduction rules. Suppose we have n (usually a very big number) rules in total and there are m types of rocks in our universe, for any unknown sample, we judge its rock type by each of those rules. An unknown sample may be recognized as a different type by different rules because it is out-side our universe, and we accept the most frequent judgment result and ignore the other m-1 types of results. Our ASAI is an improvement upon the traditional spectrum absorption index (SAI), better applicable to field spectrums: given a spectrum curve and a wavelength interval, we take the average reflectance within the interval as a base line and let ASAI=αbelow/(αabove αbelow), where αbelow and αabove stand for total areas, bounded by the curve, the base line and the borders of the intervalbelow and above the base line respectively. With the equipments of FieldSpectr Fr (made by ASD Co., US), we collected data from Baiya gold deposit, Yunnan, and applied the above method to discriminate altered rocks as an experiment. The results show satisfactory performance of the method. 相似文献
248.
普查1990~2003年河南寒潮资料,筛选出发生在11月上旬的全省性寒潮天气过程,对过程发生前5~10天的候图进行位势高度梯度分析及合成分析,从梯度场和合成图中找出秋季寒潮爆发前5~10天的特征。 相似文献
249.
L Qingtian HOU Zengqian ZHAO Jinhua SHI Danian WU Xuanzhi CHANG Yinfo PEI Rongfu HUANG Dongding & KUANG Chaoyang . Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing China . The Sixth Geophysical Exploration Brigade Petroleum Bureau of East China Nanjing China 《中国科学D辑(英文版)》2004,47(3)
Deep seismic reflection profiling has been the dominant method for probing the deep structure of continental crust since the initiation of the COCORP in 1974[1,2]. Over the past few decades, this tool has been applied to diverse geologic features from the Appalachian area of the United States, to the Rhine-graben area in Western Europe and to the Tibetan Pla-teau[36]. In recent years, the Australian Geodynamic Cooperative Research Center ( AGCRC ) has applied this technique to the stu… 相似文献
250.
The Jiyang Sag and the Liaohe Basin are the two important areas where immature oil resources are distributed in China. From
these two areas immature-low mature to mature oil samples were collected for carbon isotopic analysis. The extracts of source
rocks are dominant in the Jiyang Sag while crude oils are dominant in the Liaohe Basin. The maturity index, Ro, for source rocks varies from 0.25% (immature) to 0.65% (mature). Studies have shown that within this range of Ro values the extracts of source rocks and crude oils, as well as their fraction components, have experienced observable carbon
isotope fractionation. The carbon isotopic values tend to increase with burial depth, the oils become from immature-low mature
to mature, and the rules of evolution of oils show a three-stage evolution pattern, i. e., light→heavy→light→heavy oils. Such
variation trend seems to be related to the occurrence of two hydrocarbon-generating processes and the main hydrocarbon-forming
materials being correspondingly non-hydrocarbons and possessing MAB characteristics, lower thermodynamic effects and other
factors. In the process towards the mature stage, with increasing thermodynamic effects, the thermal degradation of kerogens
into oil has become the leading factor, and correspondingly the bond-breaking ratio of12C-13C also increases, making the relatively12C-rich materials at the low mature stage evolve again towards13C enrichment.
This research project was granted by both the 960006 Project of China Petroleum and Natural Gas Co. and the National Natural
Science Foundation of China (Grant No. 49973010). 相似文献