To analyze the episodic alteration of Middle Permian carbonate reservoirs by complex hydrothermal fluid in southwestern Sichuan Basin, petrology, geochemistry, inclusion and U-Pb dating researches are conducted. The fractures vugs Qixia–Maokou formations filled with multi-stage medium−coarse saddle dolomites associated minerals, which indicates that early limestone/dolomite was caused large-scale, high-temperature, deep magnesium-rich brine along flowing channels such as basement faults or...

Based on outcrop characteristics, combined with regional tectonic background, drilling and geophysical data, the sedimentary characteristics of Middle Permian Maokou Formation in northern Sichuan Basin was studied by means macroscopic microscopic observation, geochemical element test, total organic carbon content vitrinite reflectance measurement. There is a set deep-water sediments rich matter Guangyuan-Wangcang area during late depositional period Formation. The strata are distributed from...

The Late Ediacaran Dengying Formation, located in the Sichuan Basin of northwestern Yangtze Craton, is significant interest oil and gas exploration due to its abundant pores vugs within microbial mound-shoal complexes. However, there still uncertainty regarding spatiotemporal distribution controlling factors platform margin. This study comprehensively analyzes retrogradation pattern Formation margin using seismic data, well logs, field outcrops, petrological characteristics. Our findings...

Abstract This study investigated the characteristics and genesis of reservoirs in 2nd 4th members Sinian Dengying Formation northern Sichuan its surrounding areas, on basis outcrop, drilling cores thin section observation geochemical analysis. The member are distributed middle part stratum. reservoir quality is controlled by supergene karst distribution mound-shoal complex. bedded elongated isolated algal framework solution-cave residual “grape-lace” cave, which partially filled with...

Volcaniclastic rocks are important unconventional oil and gas reservoirs from which it is difficult to determine the protolith due strong metasomatic alteration. Intensive alteration has occurred in much of western China, but few robustly documented examples known assess processes. Further recognition petrological mineralogical record essential quantify diagenetic environment, degree alteration, its impacts. Permian volcanic widely developed Sichuan Basin (southwestern China), with a...

摘要: 为明确克拉美丽气田滴西地区石炭系蚀变熔结凝灰岩储层经历的流体作用及成岩孔隙演化过程,利用铸体薄片观察、扫描电镜、电子探针、阴极发光、荧光、微量/稀土元素分析及U-Pb同位素定年等方法技术开展综合研究.结果表明,火山碎屑物质的溶解及成岩转化为自生矿物的形成提供了物质基础;成岩过程中因埋藏、生烃、热液充注等活动而产生的成岩环境改变是控制区内孔隙形成及演化的重要因素:伴随着有机质的成熟,有机酸溶蚀形成大量晶屑铸模孔并在孔隙中沉淀出高岭石及石英;随着酸性流体向碱性转变,在溶蚀孔隙中沉淀出钠长石以及方解石,其充填作用使孔隙急剧减少;燕山中期(135±27...

Middle Permian Qixia Formation in the southwestern region of Sichuan (SW China) has experienced multiphase fluidisation, resulting an unclear understanding reservoir reconstruction effect. In this study, a systematic analysis Qi2 member Wulong Town was carried out by combining field outcrop petrology and geochemistry. The results demonstrated that multiple sets crystalline dolomite-bioclastic limestone cycles were stacked vertically member, accompanied development fractures karst channels....

The Sinian Dengying Formation in the Sichuan basin is an important potential reservoir for oil and gas exploration periphery of basin. Its reservoirs were well developed. And many kinds fillings which lead to decrease pores can be seen caves. In this paper, pore are object study. types characteristics studied detail by means rock slices analysis, cathode luminescence, trace elements inclusion temperature measurement. study shows that include dolomite siliceous quartz bitumen fillings. Among...

A breakthrough has been recently made in the hydrocarbon exploration of Permian pyroclastic rocks Jianyang Area, western Sichuan Basin, China. With an aim to decipher impacts eruption environment, temperature hydrothermal fluids, and paleo-salinity on formation authigenic mineral assemblage pores, this study implements comprehensive petrographic geochemical studies through integrated core thin section analyses. The data presented demonstrate that volcanic intervals are intensively affected...

The Carboniferous Batamayineishan Formation of the Kelameili Gas Field is a specific weathered crust-related volcanic reservoir that has significant production rate in Junggar Basin, Northwestern China, attributed to debatable processes fluid evolution. results suggest various types fluids occurring rocks lead filling quartz and calcite fractures their associated alteration haloes. silica formed veins was mainly derived from deep hydrothermal fluids, while carbon dioxide originated sources...

Agate, a distinctive form of banded chalcedony, derives its characteristic appearance from the deposition silica and presence impurities. A significant variety agate-bearing calcite was identified in Permian Emeishan Basalt located southwestern Sichuan Basin. This calcite-bearing agate provides valuable insights into complex interplay evolution fluids minerals. study aims to provide detailed description analysis microscopic textural geochemical characteristics agate, while elucidating...

Microbialite reservoirs are of great importance in oil and gas exploration. However, there is still a lack comprehensive studies on the formation mechanisms thrombolitic reservoirs, specific type microbialite. This research focuses oldest dolomite reservoir located within Precambrian Dengying Formation central Sichuan Basin, southwestern China. A multi-disciplinary approach was employed to characterize different thrombolite facies elucidate mechanism their controlling factors, involving core...

Based on stratigraphic variations of petrology, geochemistry (major, trace elements), and pyrite framboids, we study the sedimentary environment siliceous rocks Wufeng Formation in Wuxi, Northeastern Chongqing, China. Coupled Al2O3/(Al2O3+Fe2O3), SiO2/Al2O3, with Al–Fe–Mn values indicate that are deposited a continental margin influenced by detrital input. UEF-MoEF V/Cr–U/Th cross-plots suggest shale was formed dysoxic to anoxic conditions. Redox proxies imply lower, middle upper, top part...

To build the palaeo-redox environment model of Longmaxi Formation shale during Silurian Rhuddanian stage in Southern Sichuan Basin, China, 20 core samples taken from wells W201 and N1 were determined by carbon-sulphur analyser, X-ray fluorescence (XRF) spectrometry, inductively coupled plasma-mass spectrometry (ICP-MS) to test for major trace elements.Major elements results shows that fragile mineral SiO 2 component degree total pyritization section A is greater than B, demonstrating...

As a main tool, the technique of 3‐D seismic exploration is becoming mature (Brow, 1996), precision and resolution data are higher, computer visualization also more excellent. With improvement exploration, those simple reservoirs have been gradually found. However complex lithologic unconventional brings severe challenge to scientific researchers. It will take one or two months carry out interpretation fault system in areas. If we use conventional techniques, general analysis may be affected...