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111.
A Study on Organic Inclusions in Clastic Reservoir Rocks and Their Application to the Assessment of Oil and Gas Accumulations 总被引:5,自引:0,他引:5
Terrigenous clastic reservoir rocks are widespread in China,and nearly all the industrial oil and gas accumulations in eastern China occur in the clastic rocks.The study shows that organic inclusions are mostly distributed in the secondary fissures and pores which were ormed in the process of oil-rock interaction,rather than in the cements or secondary enlargements. The organic inclusions are dominantly organic gas-rich or are composed of pure hydrocarbons.Homogenization temperatures range mainly from 120℃ to 130℃,which shows a relatively high maturity of organic matter.Vertical and horizontal temperature changes provide the grounds for the investigation of basin evolution and thermal fluid-kinetics-model.Fluorescence spectral characteristics o the organic inclusions indicate that oils and gases in the area studied probably have experienced two-stage or two-time migration.Micro-fluorescence rescearch is one of the effective approaches to oil/source correlation and oil migration-stage determination.The abundance and occurrence of organic inclusions is one of the indicators of oil and gas abundance and accumulation in rock layers.With the help of other informatio,organic inclusions can provide the basis for the prospective assessment of oil and gas in clastic reservoir rocks. 相似文献
112.
滇西南澜沧群多硅白云母的多型和化学成分特征及其意义 总被引:5,自引:0,他引:5
从理论、实验及实际观察的结果都表明,随着压力的增加白云母中绿鳞石的含量显著地增加,可以认为在多期变质作用过程中,尤其是在变质压力不同的多期变质作用下,形成的多硅白云母,其化学成分就会打上不同的烙印。77个多硅白云母化学成分的统计结果表明,澜沧群低级变质岩中的多硅白云母有两种成因。在Na-Mg相关图上,反映了高压和中压变质特征,高压变质的多硅白云母约占70%。这与用多硅白云母b0值鉴别的高压和中压变质是相吻合的。多硅白云母的多型为3T和2M1型,以2M1型为主 相似文献
113.
114.
115.
Yousheng Xu Hongsen Xie Jie Guo Haifei Zheng Yueming Zhang Maoshuang Song 《中国科学D辑(英文版)》1997,40(4):398-402
NaCI-H2O is the most fundamental ternary system in geology. Until now, the measurements of electrical conductivity of NaCl solutions
are still little at high pressures (> O.5 GPa) We measured the conductivity of 0.01 m NaCl solution at 0.4–5.0 GPa and 25-500°C.
The results are consistent with that of Quist and Marshall (1968) at 0.4 GPa. The conductivity of NaCl solution increases
with increasing temperature. The results also show that the conductivity of NaCl solution changes little with increasing pressure
below 1.5 GPa and changes rapidly with increasing pressure above 1.5 GPa. The rapid increase of the conductivity of NaCl solution
may play an important role in many geological processes (such as the genesis of ore deposits under hydrothermal condition)
and other fields.
Project supported by the National Natural Science Foundation of China. 相似文献
116.
Crustal structure of Dabieshan orogenic belt 总被引:2,自引:0,他引:2
Chunyong Wang Xiankang Zhang Buyun Chen Xuebo Chen Songyan Song Jinhan Zheng Hongxiang Hu Hai Lou 《中国科学D辑(英文版)》1997,40(5):456-462
The crustal structures ofP velocity and density on the deep seismic sounding profile across the Ilabieshan orogenic belt are presented. There is a 5-km-thick
crustal “root” between the Yuexi and Xiaotian where the elevation is highest on the profile. An apparent Moho offset of 4.
5 km beneath the Xiaotian-Mozitan fault marks the paleo-suture of the Triassic collision. A high-velocity anomaly zone at
the depth below 3 km beneath the ultra-high pressure (UHP) zone may be correlated to the higher content of UHP metamorphic
rocks.
Project supported by the National Natural Science Foundation of China and the Joint Earthquake Science Foundation. 相似文献
117.
Song-Yan Song Xue-Song Zhou Chun-Yong Wang Xian-Kang Zhang Jian-Li Song Yi Gong 《地震学报(英文版)》1997,10(1):15-25
On the basis of S wave information from Tai’an-Xinzhou DSS profile and with reference to the results from P-wave interpretation,
the 2-D structures, including S-wave velocity V
s, ratio γ between V
p and V
s; and Poisson’ s ratio σ, are calculated; the structural configuration of the profile is presented and the relevant inferences are drawn from the
above results. Upwarping mantle districts (V
s≈4.30 km/s) and sloping mantle districts (V
s≈4.50 km/s) of the profile with velocity difference about −4% at the top of upper mantle are divided according to the differences
of V
s, γ and σ in different media and structures, also with reference to the information of their neighbouring regions; the existence of
Niujiaqiao-Dongwang high-angle ultra-crustal fault zone is reaffirmed; the properties of low and high velocity blocks (zones)
including the crust-mantle transitionalzone and the boudary indicators of North China rift valley are discussed. A comprehensive
study is conducted on the relation of the interpretation results with earthquakes. It is concluded that the mantle upwarps,
thermal material upwells through the high-angle fault, the primary hypocenter was located at the crust-mantle juncture 30.0∼33.0
km deep, and additional stress excited the M
S=6.8 and M
S=7.2 earthquakes at specific locations around 9.0 km below Niujiaqiao-Dongwang, the earthquakes took place around the high-angle
ultra-crustal fault and centered in the brittle media and rock strata with low γ and low σ values.
This subject is part of the 85-907-02 key project during the “8th Five-Year Plan” from the State Science and Technology Commission. 相似文献
118.
Based on characteristics and trap types of gas reservoirs in large and medium gas fields in China, 4 gas reservoir models
have been established:(i) structural trap gas reservoir model I, formed earlier than or simutaneously with generating of gases;
(ii) structural trap gas reservoir model II, formed later than generating of gases; (iii) fossil weathered residuum gas reservoir
model; and (iV) mud diapir abnormal temperature and pressure gas reservoir model. Distribution patterns of large-medium gas
fields are described with the concept of “sealed compartment”. It is concluded that the inner-compartment area, marginal area
of the compartment and the areas between two overlapped sealed compartments are the most favourable areas for discovering
large-medium gas fields.
Project supported by the “85–102” Chinese National Key Science and Technology Project. 相似文献
119.
本文通过年代学资料和其它地质依据建立了冀西北及邻区麻粒岩地体早前寒武纪主要地质事件的年代格架。早期的基性火山喷发事件发生在2868—2932Ma期间,形成本区的早期地壳。在2761Ma左右发生了大规模的TTG岩浆侵位事件,在2650Ma时发生了基性岩浆侵位,使地壳加厚。在2561—2503Ma期间,花岗闪长质岩浆在本区广泛侵入,使地壳进一步加厚。2477—2461Ma期间,紫苏花岗岩以岩株形式侵入,同时发生区域麻粒岩相变质,早期地壳受到改造。大约在2300Ma时发生第二阶段的麻粒岩相变质。此后,在2144—2087Ma期间红色花岗岩侵位,形成花岗岩带。 相似文献
120.
珊瑚礁工程地质研究的内容和方法 总被引:3,自引:0,他引:3
珊瑚礁工程地质研究的主要内容为珊瑚礁自然地质条件、珊瑚礁岩土物理力学性质和珊瑚礁混凝土料问题。除了通常的工程地质研究方法外, 着重介绍珊瑚礁工程地质研究的钻探、触探和地球物理勘测方法。 相似文献