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11.
云南地壳形变与丽江7.0级地震 总被引:9,自引:5,他引:9
本利用滇西、滇中地区大地垂直形变和跨断层短水准、短基线的监测资料进行综合分析论证,其结果表明:1996年2月滇西丽江7.0级地震前,该区应力场方向自1990年以来产生了由北东-北西的转变,震源区出现高达109mm的垂直差异运动1993-1996年有75%的断层形变测点相继出现不同程度的中期、短期和临震异常。大地垂直形变与断层形变的共性演变特性,为强震的预测提供了一个较好的震例。 相似文献
12.
本文通过对辽西及邻区中生代盆地火山岩稀土元素配分特征的研究及模拟运算,探讨了其岩浆成因及过程。结果显示南北岩区岩浆成因不同,南岩区岩源为MORB地幔和长期富集型幔熔融混合而成,北岩区为MORB和近期亏损型地幔熔融混合而成。 相似文献
13.
遥感技术获取的可见光、红外及微波信息,可以对化工企业及化学矿山环境污染(水、粉尘、大气、废渣污染等)及环境地质灾害(滑坡、泥石流、地面塌陷等)进行实时动态监测,并可获得较高的社会经济效益,达到地面环保及常规环境地质工作难以达到的效果。特别是对重点大中型化工企业及化学矿山建立环境遥感信息动态监测系统,可以为国家决策部门及时准确地提供环境治理和改造的依据。 相似文献
14.
Application of discovery process models in estimating petroleum resources at the play level in China
Discovery process modeling has gained wide acceptance in the Chinese exploration community. In recent years, a variety of
discovery process models have been applied to the prediction of undiscovered petroleum resources at the play level in sedimentary
basins in China. However, challenging problems have been encountered, particularly when one method alone has been applied
to small plays in nonmarine sedimentary basins or in plays with an unusual order of discovery wells. This paper presents results
gotten by using the lognormal discovery process model of the Geological Survey of Canada and the geoanchored method for three
petroleum plays in basins with different geologic settings. Although the predicted shapes of the parentsize distributions
which use these two models, were not always similar, the expected values of the total resources and the number of fields (pools)
to be discovered are comparable. The combined use of two discovery process models in the same play compensates for the weaknesses
in one method compared with the other and vice versa. Thus, more reliable estimates are the result. 相似文献
15.
陕西子长油田成藏地质特征 总被引:2,自引:0,他引:2
从烃源岩、储集层、圈闭、油气运移及富集条件等方面入手,对子长油田成藏地质特征进行了研究。认为子长油田延长组油气生成及油气初次运移条件均较好,但储层、油气二次运移及富集条件相对较差。延长组主要有五种油藏类型,油气分布主要受储层物性、岩性、岩相等条件所控制。 相似文献
16.
Sm/Nd isotopic age determination showed that Xiongshan dike swarm was at 585.7 Ma ± 30 Ma. The trace element geochemistry
and Sr/Nd/Pb isotope gemhemistry studies indicate that the dike swarm was products of back-arc basin spreading ridge and the
magma originated from the depleted mantle region which was metasomatized by LILE-rich liquids/melts derived from subduction
slab.
Project supported by the National Natural Science Foundation of China. 相似文献
17.
Yuhong Liao Ansong Geng Yongqiang Xiong Dehan Liu Jialan Lu Jinzhong Liu Haizu Zhang Xinhua Geng 《Organic Geochemistry》2004,35(11-12):1479
Expulsion of petroleum from source rock is a complex part of the entire migration process. There exist fractional effects on chemical compositions in hydrocarbon expulsion. Does the carbon isotopic fractionation occur during expulsion and to what extent? Here the influence of hydrocarbon expulsion on carbon isotopic compositions of individual n-alkanes from pyrolysates of selected terrestrial kerogens from Tuha basin and Fushun, Liaoning Province of China has been experimentally studied. The pyrogeneration-expulsion experiments were carried out under semi-closed system. The carbon isotopic compositions of individual n-alkanes were measured by GC-IRMS. The main conclusions are as follows. First, there is carbon isotopic fractionation associated with hydrocarbon expulsion from Type III kerogens in Tuha Basin. There exist differences of carbon isotopic compositions between the unexpelled n-alkanes and expelled n-alkanes from Tuha desmocollinite and Tuha mudstone. Second, there is almost no carbon isotopic fractionation associated with hydrocarbon expulsion from Type II kerogens in Fushun and Liaohe Basin. Third, carbon isotopic fractionation in hydrocarbon expulsion should be considered in making oil-source correlation of Type III kerogens at least in the Tuha Basin. Further studies need to be carried out to determine whether this is true in other basins. Fourth, oil and source at different maturity levels cannot be correlated directly for Type III kerogens since the carbon isotopic compositions of expelled hydrocarbons at different temperatures are different. The expelled hydrocarbons are usually lighter (depleted in 13C) than the hydrocarbons remaining in the source rock at the same maturity. 相似文献
18.
龚新华 《地震地磁观测与研究》2005,(Z1)
长沙地震台北东方向深源地震的记录中,发生于日本海边缘和中朝俄接界区域的深源地震存在sP震相,它超前于S波,由于震相能量较大,容易与S波相混淆。本文讨论了如何对它进行辨别。 相似文献
19.
20.
Emissions of biogenic sulfur gases (hydrogen sulfide (H2S) and carbonyl sulfide (COS)) from Phragmites australis coastal marsh in the Yellow River estuary of China were determined during April to December in 2014 using static chamber-gas chromatography technique with monthly sampling. The results showed that the fluxes of H2S and COS both had distinct seasonal and diurnal variations. The H2S fluxes ranged from 0.09 μg/(m2·h) to 7.65 μg/(m2·h), and the COS fluxes ranged from–1.10 μg/(m2·h) to 3.32 μg/(m2·h). The mean fluxes of H2S and COS from the P. australis coastal marsh were 2.28 μg/(m2·h), and 1.05 μg/(m2·h), respectively. The P. australis coastal marsh was the emission source of both H2S and COS over the whole year. Fluxes of H2S and COS were both higher in plant growing season than in the non-growing season. Temperature had a dramatic effect on the H2S emission flux, while the correlations between COS flux and the environmental factors were not found during sampling periods. More in-depth and comprehensive research on other related factors, such as vegetation, sediment substrates, and tidal action is needed to discover and further understand the key factors and the release mechanism of sulfur gases. 相似文献