首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The zones of deconsolidation and consolidation in the lower parts of the sedimentary cover and in the basement are considered as an important exploration indicator of oil-gas accumulation zones. The described zones are mapped using geodensity modeling (in a gravity field) in the MZ-PZ basement and Cretaceous deposits of South Sakhalin, as well as in the pre-Jurassic basement and plate complex of the central part of West Siberia. It was found that the most promising zones are confined to the Central Sakhalin Fault and Krasnoleninsk arch in Sakhalin and to the Visim megaswell in the West Siberian plate. Recent prospecting drilling revealed that deconsolidation zones are correlated with hydrocarbon reservoirs. The presented technique of geodensity modeling can be applied for petroleum-geological explorations of structures formed in different geological and tectonic settings.  相似文献   

2.
Apatite fission-track (AFT) thermochronological modeling as a diagnostic tool for periods of stability (peneplanation) and tectonic activity (orogeny) has been broadly used in tectonic studies of Central Asia in recent years. We discuss more than 100 AFT ages of samples from the Kyrgyz Tien Shan and Altai and compare them with AFT data from northern Kazakhstan. Geological, geomorphological, and AFT data indicate intense activity in the Late Cenozoic Eurasian continental interior. The impact from the India-Eurasia collision on the northern Tien Shan, Altai, and northern Kazakhstan regions showed up at 11, 5, and 3 Ma, respectively, as a result of stress propagation into the continent, with the ensuing reactivation and mountain growth. We hypothesize that a distant effect of the Late Cenozoic India-Eurasia collision was to rejuvenate Paleozoic fault zones and to deform the Mesozoic sedimentary cover north of the collision front as far as the West Siberian Plate. The reactivation facilitated formation of tectonic oil and gas traps. The activity in northern Central Asia under the effect of the Indian indentation into Eurasia appears to continue and may evolve to include uplift of southern West Siberian plate with uplift.  相似文献   

3.
Present Geothermal Fields of the Dongpu Sag in the Bohai Bay Basin   总被引:2,自引:0,他引:2  
The Dongpu sag is located in the south of the Bohai Bay basin, China, and has abundant oil and gas reserves. To date, there has been no systematic documentation of its geothermal fields. This study measured the rock thermal conductivity of 324 cores from 47 wells, and calculated rock thermal conductivity for different formations. The geothermal gradient and terrestrial heat flow were calculated for 192 wells on basis of 892 formation-testing data from 523 wells. The results show that the Dongpu sag is characterized by a medium-temperature geothermal field between stable and active tectonic areas, with an average geothermal gradient of 32.0°C/km and terrestrial heat flow of 65.6 mW/m2. The geothermal fields in the Dongpu sag is significantly controlled by the Changyuan, Yellow River, and Lanliao basement faults. They developed in the Paleogene and the Dongying movement occurred at the Dongying Formation depositional period. The geothermal fields distribution has a similar characteristic to the tectonic framework of the Dongpu sag, namely two subsags, one uplift, one steep slope and one gentle slope. The oil and gas distribution is closely associated with the present geothermal fields. The work may provide constraints for reconstructing the thermal history and modeling source rock maturation evolution in the Dongpu sag.  相似文献   

4.
松辽盆地是处于西伯利亚板块、华北板块和太平洋板块所挟持的构造地带,属于佳蒙地块中的镶嵌状微地块活动造山带,为中-新生代陆相含油盆地叠合于晚古生代海相盆地之上的延变型叠合盆地。盆地内中、古生代地层,均呈"水、火"二元结构;区内火山-岩浆活动频繁,并有三多(多期、多旋回、多侵入-喷发中心)特征;具有"双机"(有机和无机)、...  相似文献   

5.
The paper presents data on Callovian foraminiferal assemblages from several wells in two localities of the West Siberian plain (Shaim oil and gas district, northwestern West Siberia, and Mykhpai field, central West Siberia). The assemblages are compared and studied in terms of space and time changes of their stratigraphy, which can make basis for a more detailed zonal subdivision as more data become available. The taxonomic compositions of the assemblages are summarized in tables for specific wells to highlight their geographic variations.  相似文献   

6.
本文根据对已有地质资料的综合研究,系统论述了吐哈盆地南缘古生代活动陆缘残片的时空分布、岩石组合和岩石化学特征,在此基础上对古亚洲洋构造演化进行了简要的探讨。该区活动陆缘残片由奥陶纪-志留纪(?)、泥盆纪、石炭纪火山沉积岩系和泥盆纪、石炭纪深成岩组成。这些不同时代岩浆岩的时空分布揭示出该区弧岩浆前锋带的演化具有向南逐渐迁移的特点。这些不同时代的火山岩和深成岩在岩石组合和岩石化学方面都类似于钙碱系列弧岩浆岩。它们的这些特征,结合它们的区域地质背景,使我们得出如下初步结论:它们的形成演化与以南侧康古尔塔格碰撞带中的洋壳残片为代表的古洋岩石圈板块向西伯利亚古板块之下的俯冲有关;它们很可能是出露在阿尔泰山南侧、蒙古南部和大兴安岭中部等地的类似杂岩一起构成了古亚洲洋中西伯利亚古板块活动陆缘;该活动陆缘的发育,提示出古亚洲洋板块向西伯利亚古板块之下的俯冲在奥陶纪至古炭纪期间一直在持续进行。  相似文献   

7.
The distributions of stable carbon and oxygen isotopes in modern and ancient limestones of various types were studied. Carbonate samples from modern sediments were collected in the Black and Barents Seas. Ancient carbonates were represented by Upper Jurassic (Kimmeridgian-Tithonian) limestones from the central part of the West Siberian basin. Carbonate samples include remains of modern and Upper Jurassic fauna, carbonate crust from sediments of the Black Sea, carbonate tube from sediments of the Barents Sea, and Upper Jurassic limestone from the carbonate layer found at top of Abalak, bottom of Bazhenov deposits in the central part of the West Siberian basin. According to the results of the isotope analysis and comparison with modern carbonates, Upper Jurassic limestones of the West Siberian basin belong to the group of methane-derived carbonates and precipitated as a result of anaerobic oxidation of methane (AOM). Fractures in limestones are filled with secondary calcite.  相似文献   

8.
The HC-rich Upper Cretaceous rocks in the West Siberian petroliferous basin comprise genetically heterogeneous sediments, resulting in the specificity of morphology, structure, and properties of natural reservoirs therein. One of the possible techniques for more reliable predictions of reservoir rock characteristics is the utilization of results of sedimentation modeling based on the complex interpretation of borehole and seismic data. The paper presents an example of the realization of such approach for refining the structure of oil-and-gas pools in the Pokur Formation of the Russko-Chasel megaswell.  相似文献   

9.
10.
云南地热资源及其开发前景   总被引:1,自引:0,他引:1  
云南地热异常多且显著。滇西高温水热活动区是藏滇水热带的南延,滇东断陷盆地中低温水热活动区的形成得益于独特的地质结构,滇西、滇南花岗岩地热系统则主要吸收地层中K^40同位索放射热而成。开发前景极为广阔。  相似文献   

11.
川藏铁路是我国正在规划建设的重要铁路干线之一,是西部大通道的重要组成部分。该铁路线横跨扬子板块、川滇地块、羌塘地块和拉萨地块等大地构造单元,在复杂的地质构造背景条件下,川藏铁路沿线活动断裂、地震和地质灾害极为发育,严重制约着川藏铁路的规划建设。在野外地质调查、钻探、地应力测量和室内测试分析的基础上,对川藏铁路规划建设中可能遇到的活动断裂、高地应力、高地温、岩爆和地质灾害等主要环境工程地质问题进行了论述分析,认为:川藏铁路沿线及邻区发育有54条区域活动断裂,其中对铁路有直接重要影响的全新世活动断裂有17条;研究区内地震活动频繁,约有50%的规划线路位于地震动峰值加速度>02 g地区,部分地段>04 g,潜在地震风险大;铁路沿线主要的地质灾害类型为崩塌、滑坡和泥石流,地质灾害受活动断裂影响强烈,部分地段发育有高速远程滑坡;川藏铁路沿线构造应力场和地热场复杂,深埋隧道工程建设时容易发生岩爆、软岩大变形和高温热害等工程地质问题。  相似文献   

12.
为了确定四川盆地原油裂解气的有利分布区,利用镜质体反射率古温标重建了四川盆地的热演化史,分析了四川盆地下三叠统飞仙关组原油裂解的有利地温场分布范围及其演化特征。结果表明:四川盆地各构造单元自三叠纪以来的热流演化是不一致的,川东北地区热流在地质历史时期最低,川中地区热流也较低,而川西北和川西地区热流演化最高,这种差异与青藏高原隆升及峨眉山玄武岩地幔柱有关;四川盆地在二叠纪时期热流明显高于其他时期,但高热流持续时间较短,这主要受岩浆侵入的影响;四川盆地飞仙关组原油裂解气的有利地温分布区是不断变化的,侏罗纪末期其几乎遍及整个四川盆地,白垩纪末期其范围缩小,古近纪末期其收缩至川西和川中部分地区,现今范围则最小,主要分布在川西部分地区;控制原油裂解气分布区的主要因素是古地温场,尤其是地温最高时期的地温场,而与现今地温场的关系并不密切。  相似文献   

13.
通过分析输人模型的参数对输出结果的影响,可以确定影响烃源岩成熟度史模拟的敏感性参数.本文应用Easy% Ro化学动力学模型,以普光5井为例,对川东北地区各期构造运动剥蚀厚度、古地表温度和古地温梯度进行了相关的敏感性分析.分析结果表明:研究区下寒武统、下志留统、下二叠统和上二叠统烃源岩现今成熟度状态完全受控于燕山运动晚幕...  相似文献   

14.
We discuss the results of measurements of the thermal conductivity of the Bazhenovo Formation rocks from wells drilled in the Salym petroliferous area of the West Siberian Plate. The thermal conductivity was measured by “Thermal-conductivity comparator” and “Scanning thermal-conductivity meter” in different years. A total of 225 measurements were made in two directions with respect to the rock layering: parallel (λ1) and orthogonal (λ2). The results show that the Bazhenovo Formation rocks are mostly of abnormally low thermal conductivity: λ1 = 1.0–2.3 W/(m⋅K) (average is 1.6 W/(m⋅K)) and λ2 = 0.8–1.9 W/(m⋅K) (average is 1.3 W/(m⋅K)). This leads to an abnormal increase in geothermal gradient within the Bazhenovo Formation. Such geothermal-gradient anomalies can be easily revealed by high-precision thermal logging. It is also shown that the thermal conductivity of the studied rocks is in inverse relationship with their organic-matter content.  相似文献   

15.
Regional heat flow patterns in the Western Canadian Sedimentary Basin   总被引:2,自引:0,他引:2  
The regional geothermal pattern of the Western Canadian Sedimentary Basin has been studied using available temperature data from wells. Average heat conductivity for various geological formations has been estimated on the basis of net rock studies by Canadian Stratigraphie Services. These data and observations of temperature made in “shut-in holes” in some of the oil pools have been used in heat flow estimations by the Bullard method.The geothermal gradient and heat flow within the basin are exceptionally high in comparison with the other world wide Precambrian platform areas. Especially high geothermal gradient areas are found in the northwestern part of the Prairies Basin in Alberta and British Columbia and most of southeastern and southwestern Saskatchewan. Areas of low gradient are found mainly in the Disturbed Belt of the Foothills, southern and southeastern Alberta, and the Peace River area in British Columbia. Neither the analysis of regional heat conductivity distribution nor the heat generation distribution of the basement rock of the Prairies Basin evaluated on the basis of U, Th and K data after Burwash (1979), explain the observed heat flow patterns of the Prairies Basin. Comparison of heat flow patterns with some of the hydrogeological phenomena suggests the significant influence of fluid flow in the basin formations on geothermal features. Low geothermal gradient areas coincide with water recharge areas and high hydraulic head distribution regions.The phenomenon of upward water movement in the deep strata and downward flow through much of the Cenozoic and Mesozoic strata seems to control the regional heat flow distribution in the basin. The analyses of coal metamorphism in the upper and middle Mesozoic formations of the Foothills Belt and in the central Prairies Basin suggest that the pre-Laramide paleogeothermal heat flow distribution was different from the present one. It is very probable that the Foothills Belt area was characterized by a higher geothermal gradient than the central part of the Prairies Basin, i.e. opposite to the present picture.  相似文献   

16.
Research on Formation Mechanisms of Hot Dry Rock Resources in China   总被引:3,自引:0,他引:3  
As an important geothermal resource, hot dry rock(HDR) reserves have been studied in many countries. HDR resources in China have huge capacity and have become one of the most important resources for the potential replacement of fossil fuels. However, HDR resources are difficult to develop and utilise. Technologies for use with HDR, such as high–temperature drilling, reservoir characterisation, reservoir fracturing, microseismic monitoring and high–temperature power stations, originate from the field of oil and drilling. Addressing how to take advantage of these developed technologies is a key factor in the development of HDR reserves. Based on the thermal crustal structure in China, HDR resources can be divided into four types: high radioactive heat production, sedimentary basin, modern volcano and the inner–plate active tectonic belt. The prospective regions of HDR resources are located in South Tibet, West Yunnan, the southeast coast of China, Bohai Rim, Songliao Basin and Guanzhong Basin. The related essential technologies are relatively mature, and the prospect of HDR power generation is promising. Therefore, analysing the formation mechanisms of HDR resources and promoting the transformation of technological achievements, large–scale development and the utilisation of HDR resources can be achieved in China.  相似文献   

17.
The modeling of carbon isotope kinetics of natural gas is an issue driving pioneering research in the oil and gas geochemistry in China and internationally. Combined with the sedimentary burial history and basin geothermal history, the modeling of carbon isotope kinetics provides a new and effective means for the determination of the origin and accumulation history of natural gas pools. In this paper, we introduce themodeling of carbon isotope kinetics of natural gas formation and its applications to the assessment of natural gas maturity, the determination of the gas source, the history of gas accumulation, and the oil-gas ratio. It is shown that this approach is of great value for these applications. The carbon isotopic characteristics of natural gas are not only affected by the gas source and maturity of the source rock, but also are related to the accumulation condition and geothermal gradient in a basin. There are obvious differences in the characteristics of carbon isotope ratios between instantaneous gas and cumulative gas. Different basins have different kinetic models of carbon isotope fractionation, which depends on the gas source condition, the accumulation history and the sedimentary-tectonic history. Since the origin of natural gas in the superimposed basin in China is very complicated, and the natural gas pool is characterized by multiphase and variable gas-sources, this paper may provide a new perspective on the study and evaluation of natural gas.  相似文献   

18.
Previous models for the tectonic evolution of northeastern Siberia have proposed the existence of a Kolyma plate composed of the Kolyma and Omolon massifs of presumed Precambrian age. Lithologic similarities between the Siberian platform and the Cherskiy Mountains and the presence of oceanic and island arc type deposits in the Kolyma-Indigirka interfluve suggest that no such plate exists. The eastern margin of the Siberian plate is suggested to lie along a line between the Ulakhan Sis Range, the Alazeya uplift and the Arga Tas Range; the Cherskiy Mountains and the Verkhoyansk fold belt are parts of the Siberian plate. The Paleozoic deposits of the Omolon massif are unlike those found in the Cherskiys or Siberia. Paleomagnetic data from the Omolon massif are discordant from data from Siberia. It is suggested that the Omolon massif represents a microplate which accreted onto Siberia in the Jurassic. Ophiolites in central Chukotka are of the same emplacement age as in the western Brooks Range and may have been emplaced at the initiation of the rotation of Arctic Alaska. Geometric and limited stratigraphic data suggest that the East Siberian Sea may be floored by oceanic crust left by an incomplete closure between Arctic Alaska, Siberia and Omolon. The tectonic position of the Prikolymsk massif remains ambiguous.  相似文献   

19.
20.
The tectonic scheme of the Siberian Craton proposed in this paper is compiled on the basis of a geological map of the craton prepared from numerous magnetometric maps and gravity measurements on various scales, the scheme of axes of magnetic anomalies, and the synthesis of geological information on the exposed territories. The shields and platform territories of the ancient Siberian Craton comprises Archean blocks and Paleoproterozoic foldbelts. The granite-greenstone terranes and granulite-gneiss domains were formed in the Meso- and Neoarchean. The granite-greenstone terranes exposed and overlapped by sedimentary cover are identical, although they generally differ in internal structure and rock compositions both at the infra- and supracrustal levels. The Archean granulite-gneiss domains are recognized either as special tectonic units or as deep sections of granite-greenstone terranes. Two groups of the Paleoproterozoic collisional belts that amalgamated separate Archean blocks of the Siberian Craton into a common stable structural unit evolved 2.1–1.9 and 1.9–1.8 Ga ago. Three types of deep faults arose in the Paleoproterozoic: (1) translithospheric fault zones as boundaries of tectonic blocks and collisional belts, (2) intracrustal fault zones that originated as a result of nonuniform uplift of particular segments of the common plate, and (3) transcrustal zones formed in a plate that overrode another, plunging plate.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号