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101.
塔里木盆地大中型油气田形成及分布规律   总被引:7,自引:2,他引:5  
目的 探讨塔里木盆地油气藏形成及分布规律,为油气田勘探部署提供依据。方法 运用石油地质综合研究方法,探讨了区域构造背景,有效烃源岩分布及其成熟度、储盖组合、后期构造变动等对塔里木盆地大中型油气田形成及分布的控制作用。结果 塔里木盆地油气分布十分复杂,油气藏形成及分布受多重因素控制;早期形成、长期继承发育的大型稳定古隆起及其斜坡以及前陆逆冲带第2,3排构造分别是大中型油气田形成的最有利地区;古隆起控油、斜坡富集以及隆起高部位油气易发生调整、斜坡部位有利于保存,是克拉通区油气藏形成和分布的重要特点;已发现的油气藏具有多期成藏、晚期调整的特点,早期形成的原生油气藏后期特别是晚喜山期普遍受到了调整改造,以克拉通区海相油气藏最为突出;保存条件对塔里木盆地油气藏形成与分布具有重要控制作用,特别是优质区域盖层的存在,是大中型油气田形成和保存的关键。结论 继承性古隆起与隐伏前陆逆冲带是塔里木克拉通区与前陆区寻找大中型油气田的最有利地区。  相似文献   
102.
An angiosperm compression flora is found in Palaeogene from Lanzhou Basin and the cuticular analysis of Populus davidiana Dode in the flora is carefully made. Furthermore, the fossil cuticles are compared with the epidermal structures of extant Populus leaves growing in different environments, i.e. moist, semimoist, and semiarid to arid climatic regions. The present experiments indicate that mature leaves of P. davidiana show leaf size from big to small, leaf cuticles from thick to thin and anticlinal walls of epidermal cells from faintness to clarity along with the increase of lattudes of the plant distributions, the climatic variation from moist to arid, the annual precipitation from more to less and the annual mean temperature from high to low. The fossil P. davidiana differs from the specimens collected from Shandan in semiarid to arid climatic regions but closely resembles the Wushan leaves in a semi-moist climatic area in a lot of features. In a word, the new research may reflect that the flora lives in a semi-moist climatic environment. The present discovery of compression of Paleogene Populus davidiana is of great significance to studying vegetation types, climatic and environmental changes during the primal uplifting of the Qinghai-Tibet Plateau.  相似文献   
103.
<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   
104.
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   
105.
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   
106.
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   
107.
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   
108.
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   
109.
Zircon U-Pb geochronology of basement metamorphic rocks in the Songliao Basin   总被引:23,自引:0,他引:23  
Zircon LA-ICP MS U-Pb dating of six metamorphic rocks and a metagranite (breccia) from southern basement of the Songliao Basin are reported in order to constrain the formation ages of basement. The basement metamorphic rocks in the Songliao Basin mainly consist of metagabbro (L45-1), amphibolite (SN117), metarhyolitical tuff (G190), sericite (Ser) schist (N103), chlorite (Chl) schist (T5-1), biotite (Bi)-actinolite (Act)-quartz (Q) schist (Y205), and metagranite (L44-1). The cathodoluminesence (CL) images of the zircons from metagabbro (L45-1) and metagranite (L44-1) indicate that they have cores of magmatic origin and rims of metamorphic overgrowths. Their U-Pb isotopic ages are 1808±21 Ma and 1873±13 Ma, respectively. The zircons with oscillatory zoning from amphibolite (SN117) and Chl schist (T5-1), being similar to those of mafic igneous rocks, yield ages of 274 ± 3.4 Ma and 264 ± 3.2 Ma, re-spectively. The zircons from metarhyolitical tuff (G190) and Ser schist (N103) display typical magmatic growth zoning and yield ages of 424 ± 4.5 Ma and 287 ± 5.1Ma, respectively. Most of zircons from Bi-Act-Q schist (Y205) are round in shape and different in absorption degree in the CL images, implying their sedimentary detritals. U-Pb dating yield concordant ages of 427 ± 3.1Ma, 455 ± 12 Ma, 696 ± 13 Ma, 1384±62 Ma, 1649±36 Ma, 1778±18 Ma, 2450±9 Ma, 2579±10 Ma, 2793±4 Ma and 2953±14 Ma. The above-mentioned results indicate that the Precambrian crystalline basement (1808―1873 Ma) exists in the southern Songliao Basin and could be related to tectonic thrust, and that the Early Paleozoic (424―490 Ma) and Late Paleozoic magmatisms (264―292 Ma) also occur in the basin basement, which are consistent with the ages of the detrital zircons from Bi-Act-Q schist in the basement.  相似文献   
110.
分析了陕西汉水流域文献信息资源共建共享的必要性和可行性,从共享的观念、文献资源建设等方面提出了该区域文献资源共建共享的实施策略。  相似文献   
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