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131.
鄂尔多斯盆地上三叠统延长组长6油层组为一套砂、泥薄互层的组合类型,储层非均质性很强,尤以层间的非均质性最为严重,明显受基准面升、降,和可容纳空间及沉积物供给量的变化影响。通过高分辨率层序地层的短期基准面升、降旋回过程与储集物性关系的分析,建立了6种不同沉积微相的非均质性模式,探讨了向上变深、向上变浅的非对称型和向上变深后复变浅的对称型短期基准面旋回层序对储层非均质性特征的控制作用  相似文献   
132.
133.
本文分析了本世纪八十年代金衢盆地的气候变化趋势。与前三个年代(五十、六十、七十年代)比较,八十年代具有变冷,少光,洪涝灾害频繁的趋势特征。同时,春季“三寒”(倒春寒、种田寒、5月寒),晚春初夏异常高温危害,夏凉,冬暖等异常现象突出。着重分析了气候变化及灾害演变对农林环境的不利影响,讨论了九十年代气候变异趋势及其对策。  相似文献   
134.
<正> Hetianhe is a big carbonate gas field which isfound and demonstrated in the period of "Chinese NationalNinth 5-Year Plan". The proved reserve of Hetianhe gas fieldis over 600 ×108 m3. Its main producing layers are Carbon-iferous bioclastic limestone and Ordovician carbonate com-posed of buried hill. The former is stratified gas pool withwater around its side, and the latter is massive gas pool withwater in its bottom. The gases in the gas pools belong to drygases with normal temperature and pressure systems. Basedon the correlation of gas and source rock, the gases aremainly generated from Cambrian source rocks. According tothe researches on source rock and structure evolution, andthe observations on the thin section to reservoir bitumen andthe studies on homogenization temperature of fluid inclu-sions, the gas pool has been identified and divided into threeformation periods. The first is Late Caledonian when the oilgenerated from the Cambrian source rocks and migratedalong faults, as a form of liquid facies into Ordovician carbonate res-ervoir and accumulated there. After that, the crustuplifted, the oil reservoir had been destroyed. The second isLate Hercynian when condensate gases generated from theCambrian source rocks and migrated into Ordovician res-ervoir, as a form of liquid facies. Since the fractures hadreached P strata, so the trap might have a real poor preser-vation condition, and the large-scale gas pool formation hadnot happened. The third gas reservoir formation period oc-curred in Himalaya. The fractures on both sides of Hetianhegas field developed violently under the forces of compression,and thus the present fault horst formed. The dry gases gen-erated from Cambrian source rocks and migrated upwardsas the form of gas facies into Ordovician and Carboniferousreservoirs, and the large gas pool as discovered at presentwas formed finally.  相似文献   
135.
通过对塔里木盆地前震旦-石炭纪构造演化与地层组合特征的分析研究,将该盆地构造和地层系统划分为2大组合系统5个构造-地层组合.前震旦系为混合片麻岩、浅变质岩组成的地台基底,震旦纪发生板内裂陷形成坳拉槽,早寒武世-奥陶纪和石炭纪是盆地两次大的海侵期,沉积了富含烃类的碳酸盐岩建造,志留-泥盆纪为克拉通边缘隆升阶段,发育浅海相碎屑岩及碳酸盐岩建造.  相似文献   
136.
Eclogite cobbles were discovered by Wang et al. (2001) in the Fenghuangtai Formation of the northern margin of Dabie Mountains in the Dushan area of Anhui Province, China[1]. They proposed that after the formation during the Triassic, the high-pressure (HP) and ultra-high-pressure (UHP) metamorphic rocks reached the sur-face through exhumation and uplifting before the late Ju-rassic. However, they have not provided any evidence about isotopic ages. One kind of cobbles of HP-UHP rocks w…  相似文献   
137.
青藏高原若尔盖盆地草地沙化成因分析及治理对策   总被引:2,自引:0,他引:2  
根据野外调查与遥感解译,结合前人研究资料,论述了若尔盖盆地沙化草地分布特征,探讨了草地沙化日趋严重的原因,提出了对青藏高原生态研究、长江、黄河上游沙漠化的防治均具有重要意义的治理对策.  相似文献   
138.
Generally, there are some anhydrites in carbonate reservoir, as H2S is also familiar in carbonate oil and gas reservoirs. Nowadays, natural gas with high H2S concentration is usually considered as TSR origin, so there is close relationship between H2S and anhydrite. On the contrary, some carbonate rocks with anhydrite do not contain H2S. Recently, researches show that H2S is only a necessary condition of H2S formation. The reservoir porosity, sulfate ion content within formation water, reservoir temperature, oil/gas and water interface, hydrocarbon and some elements of reservoir rock have great controlling effects on the TSR occurrence. TSR deoxidizes hydrocarbon into the acidic gas such as H2S and CO2, and the H2S formation is controlled by TSR occurrence, so the relationship among reaction room, the contact chance of sulfate ion and hydrocarbon, the reservoir temperature has great influence on the TSR reaction. H2S has relatively active chemical quality, so it is still controlled by the content of heavy metal ion. Good conditions of TSR reaction and H2S preservation are the prerequisite of H2S distribution prediction. This paper builds a predictive model based on the characteristic of natural gas reservoir with high H2S-bearing. In the porosity reservoir with anhydrite, the formation water is rich in sulfate and poor in heavy metal ion. Oil and gas fill and accumulate in the gas reservoir with good preservation conditions, and they suffered high temperature later, which indicates the profitable area of natural gas with high H2S-bearing.  相似文献   
139.
阜新盆地王营-刘家煤层气藏成藏机理   总被引:1,自引:0,他引:1  
王营-刘家煤层气藏是阜新盆地最具开发前景的两个煤层气藏.从成藏条件(包括煤层空间展布、资源丰度、储层特征、封闭条件)和成藏过程(煤层气的形成和地下水动力学特征)两个方面对其成藏机理进行了系统探讨.提出:(1)王营-刘家煤层气藏主要以多煤层、巨厚煤层为特征.煤层气含量在6~10 m3/t左右,资源丰度巨大;(2)这两个煤层气藏形成于古近纪,新近纪至今为调整改造阶段,二者的边界为平安F2断层;(3)早白垩世末期主煤层就已经成熟并开始生烃(R0=0.5%~0.8%).次生热成因、次生生物成因气并存.喜山期的岩浆活动造成煤的接触变质并发生二次生烃,但影响有限;(4)该煤层气藏形成后的调整与改造都利于煤的储气能力增加;(5)岩墙的存在沟通了所有含水层和煤层,从而造成多煤层统一成藏.图5,参12.  相似文献   
140.
柴达木盆地西部第三系烃源岩生烃动力学研究   总被引:2,自引:0,他引:2  
对柴达木盆地西部第三系烃源岩进行了生烃动力学模拟实验,使用氯仿对产物抽提,结果表明抽提物的生成量不符合经典的生烃动力学规律,无法采用动力学方程模型进行分析,这可能是由于模拟实验中产生了有机酸盐的缘故.柴西烃源岩模拟实验中抽提物的生成可以概括为有机母质一有机酸盐一抽提物和有机母质一抽提物两条途径.  相似文献   
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