期刊文献+
共找到14篇文章
< 1 >
每页显示 20 50 100
Types and microstructures of pores in shales of the Ordovician Wulalike Formation at the western margin of the Ordos Basin, China
1
作者 Wuling Mo Min Wang +6 位作者 Fangwen Chen Zhengliang Huang Ying Li Yu Yan Ren Jiang Tong Lin Junfeng Cui 《Energy Geoscience》 2023年第3期100-112,共13页
Shale samples from the Ordovician Wulalike Formation at the western margin of the Ordos Basin are studied to define the types, microstructures and connectivity of pores as well as the relationships between the pore st... Shale samples from the Ordovician Wulalike Formation at the western margin of the Ordos Basin are studied to define the types, microstructures and connectivity of pores as well as the relationships between the pore structures and gas content of the samples by using experimental techniques such as high-resolution field emission scanning electron microscopy (FESEM), mercury injection capillary pressure (MICP), low-temperature nitrogen adsorption (LTNA), CO_(2) adsorption, and focused ion beam scanning electron microscopy (FIB-SEM). The results show that the shale has 10 different lithofacies, typical mixed sedimentary characteristics, and poorly developed pores. The reservoir space mainly consists of intercrystalline pores, dissolution pores, intergranular pores, and micro-fissures, with organic pores occasionally visible. The pore size is mostly within 0.4–250 nm range but dominated by micropores and mesopores less than 20 nm, with pore numbers peaking at pore sizes of 0.5 nm, 0.6 nm, 0.82 nm, 3 nm, and 10 nm, respectively. The pores are poorly connected and macropores are rarely seen, which may explain the low porosity and low permeability of the samples. Samples with high content of organic matter and felsic minerals are potential reservoirs for oil and gas with their favorable physical properties and high connectivity. The pores less than 5 nm contribute significantly to the specific surface area and serve as important storage space for adsorbed gas. 展开更多
关键词 SHALE Pore type Microstructure ORDOVICIAN Ordos Basin
下载PDF
Factors Influencing Fracture Propagation in Collaborative Fracturing ofMultiple HorizontalWells
2
作者 Diguang Gong Junbin Chen +1 位作者 Cheng Cheng Yuanyuan Kou 《Energy Engineering》 EI 2024年第2期425-437,共13页
Horizontal well-stimulation is the key to unconventional resource exploration and development.The development mode of the well plant helps increase the stimulated reservoir volume.Nevertheless,fracture interference be... Horizontal well-stimulation is the key to unconventional resource exploration and development.The development mode of the well plant helps increase the stimulated reservoir volume.Nevertheless,fracture interference between wells reduces the fracturing effect.Here,a 2D hydro-mechanical coupling model describing hydraulic fracture(HF)propagation is established with the extended finite element method,and the effects of several factors on HF propagation during multiple wells fracturing are analyzed.The results show that with an increase in elastic modulus,horizontal principal stress difference and injection fluid displacement,the total fracture area and the reservoir stimulation efficiency are both improved in all three fracturing technologies.After a comparison of the three technologies,the method of improved zipper fracturing is proposed,which avoids mutual interference between HFs,and the reservoir stimulation effect is improved significantly.The study provides guidance for optimizing the fracturing technology of multiple horizontal wells. 展开更多
关键词 Multi-well fracturing inter-fracture interference hydraulic fracturing hydro-mechanical coupling extended finite element horizontal well
下载PDF
Application of Horizontal Well Seismic Geo-Steering Technology in XX Block Development
3
作者 Xuecheng Jia Xiaoyi Cheng +4 位作者 Hui Ma Shilei Lu Xin Yang Shuo Wang Xiang Li 《Open Journal of Yangtze Oil and Gas》 2024年第3期65-74,共10页
During the development phase horizontal wells are very efficient way to improve the production in the deep coal bed methane. The 8# coal seam in the XX block on the eastern edge of the Ordos Basin has challenges such ... During the development phase horizontal wells are very efficient way to improve the production in the deep coal bed methane. The 8# coal seam in the XX block on the eastern edge of the Ordos Basin has challenges such as deep burial depth (>2000 m), thin coal sweet spot (3 m), and significant short-distance structural fluctuations. The challenges caused a high risk of missing targets and running out of the target layers, as well as difficulties in cementing and completion due to uneven well trajectories. To address these challenges, this paper focuses on solving the issues through detailed precise geological modeling, optimized trajectory design, and accurate seismic geology Steerable Drilling. 1) Based on reasonable velocity field construction and Time-Depth transformation, a precise directional model is constructed using the layer-by-layer approximation principle with reference to marker layers, improving the accuracy of the target spot and avoiding premature or delayed entry into the target;2) Based on a precise geological model, the dip angle of the strata ahead and the development of sweet spots are clearly defined, enabling optimized trajectory design for horizontal wells;3) Using “1 + N” dynamic modeling to update the geological model in real-time during the drilling process, and actively guide the drill bit through the horizontal segment smoothly by using multi-information judgment of the drill bit position. The actual drilling of 80 completed horizontal wells in this area show: That this approach effectively ensures the smooth trajectory and high-quality drilling rate of the horizontal well in the coal seam, providing a basis for subsequent hydraulic fracturing and increasing single-well production. At the same time, it has certain potential value and significance for similar coalbed methane developments under similar geological conditions. 展开更多
关键词 Seismic Geo-Steerable Horizontal Wells Coalbed Methane Marker Layers
下载PDF
Evidence of the Near-Source Accumulation of the Tight Sandstone Gas in Northern Ordos Basin,North-Central China 被引量:14
4
作者 YANG Zhi LI Qiyan +2 位作者 WU Songtao LIN Senhu LIU Xinshen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第5期1820-1835,共16页
The tight sandstone gas in Upper Paleozoic Formation of the northern Ordos Basin is a typical giant unconventional tight gas province. Evidences from geochemistry, reservoir geology and paleotectonic setting all verif... The tight sandstone gas in Upper Paleozoic Formation of the northern Ordos Basin is a typical giant unconventional tight gas province. Evidences from geochemistry, reservoir geology and paleotectonic setting all verify that the present-day tight sandstone gas accumulation in the Ordos Basin is the result of near-source accumulation. The evidences are listed as following: tight sandstone gas is mainly distributed in the area with high gas-generating strength; gas composition was not subjected tofractionation; gas saturation significantly decreases with the distance away from the source rocks; gas isotopes suggest their origin is the same and maturity is consistent with in-place source rocks; reservoirs have experienced three types of densification digenesis, including intense compaction, siliceous cementation and calcareous cementation, which took place before the formation of a large amount of tight sandstone gas, forming tight reservoirs with low porosity and permeability, fine pore throat and great capillary resistance; the paleo-structural gradient ratio is small from the main hydrocarbon generation period to present. It is indicated the present distribution of tight sandstone gas in the northern Ordos Basin is the result of near-source and short-distance migration and accumulation. 展开更多
关键词 near-source accumulation tight sandstone gas coal measures unconventional gas GEOCHEMISTRY
下载PDF
Simultaneous hydraulic fracturing of ultra-low permeability sandstone reservoirs in China: Mechanism and its field test 被引量:9
5
作者 任岚 林然 +3 位作者 赵金洲 杨克文 胡永全 王秀娟 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1427-1436,共10页
Based on the impact of the stress perturbation effect created by simultaneous propagation of multiple fractures in the process of simultaneous hydraulic fracturing, a thorough research on the mechanism and adaptation ... Based on the impact of the stress perturbation effect created by simultaneous propagation of multiple fractures in the process of simultaneous hydraulic fracturing, a thorough research on the mechanism and adaptation of simultaneous fracturing of double horizontal wells in ultra-low permeability sandstone reservoirs was conducted by taking two adjacent horizontal wells(well Yangping-1 and well Yangping-2 located in Longdong area of China Changqing Oilfield) as field test wells. And simultaneous fracturing optimal design of two adjacent horizontal wells was finished and employed in field test. Micro-seismic monitoring analysis of fracture propagation during the stimulation treatment shows that hydraulic fractures present a pattern of complicated network expansion, and the well test data after fracturing show that the daily production of well Yangping-1 and well Yangping-2 reach105.8 t/d and 87.6 t/d, which are approximately 9.4 times and 7.8 times the daily production of a fractured vertical well in the same area, respectively. Field test reflects that simultaneous hydraulic fracturing of two adjacent horizontal wells can enlarge the expansion area of hydraulic fractures to obtain a lager drainage area and realize the full stimulation of ultra-low permeability sandstone reservoirs in China Changqing oilfield. Therefore, simultaneous fracturing of two adjacent horizontal wells provides a good opportunity in stimulation techniques for the efficient development of ultra-low permeability reservoirs in China Changqing oilfield,and it has great popularization value and can provide a new avenue for the application of stimulation techniques in ultra-low permeability reservoirs in China. 展开更多
关键词 Changqing Oilfield ultra-low permeability simultaneous fracturing double horizontal wells
下载PDF
Origin and depositional model of deep-water lacustrine sandstone deposits in the 7th and 6th members of the Yanchang Formation(Late Triassic),Binchang area,Ordos Basin,China 被引量:2
6
作者 Xi-Xiang Liu Xiao-Qi Ding +1 位作者 Shao-Nan Zhang Hao He 《Petroleum Science》 SCIE CAS CSCD 2017年第1期24-36,共13页
Sandstones attributed to different lacustrine sediment gravity flows are present in the 7th and 6th members of the Yanchang Formation in the Ordos Basin, China. These differences in their origins led to different sand... Sandstones attributed to different lacustrine sediment gravity flows are present in the 7th and 6th members of the Yanchang Formation in the Ordos Basin, China. These differences in their origins led to different sandstone distributions which control the scale and connectivity of oil and gas reservoirs. Numerous cores and outcrops were analysed to understand the origins of these sandstones. The main origin of these sandstones was analysed by statistical methods, and well logging data were used to study their vertical and horizontal distributions. Results show that the sandstones in the study area accu- mulated via sandy debris flows, turbidity currents and slumping, and sandy debris flows predominate. The sand- stone associated with a single event is characteristically small in scale and exhibits poor lateral continuity. How- ever, as a result of multiple events that stacked gravity flow-related sandstones atop one another, sandstones are extensive overall, as illustrated in the cross section and isopach maps. Finally, a depositional model was developed in which sandy debris flows predominated and various other types of small-scale gravity flows occurred frequently, resulting in extensive deposition of sand bodies across a large area. 展开更多
关键词 Sediment gravity flows - Sandy debris flows -Binchang area Yanchang Formation Ordos Basin
下载PDF
Vertical structure and dominating factors of sand body during Late Triassic Chang 9 time of Yanchang Formation in Ordos Basin, NW China
7
作者 丁熊 陈景山 +5 位作者 谭秀成 林丹 赵子豪 姚泾利 邓秀芹 李元昊 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1405-1418,共14页
Based on a synthetic geological study of drilling, well logging and core observations, two main genetic types of Chang 9sand body in Odors Basin were recognized, which included two effects, that is, delta environment ... Based on a synthetic geological study of drilling, well logging and core observations, two main genetic types of Chang 9sand body in Odors Basin were recognized, which included two effects, that is, delta environment and tractive current effects that lead to the development of mouth bar, distal bar, sheet sand and other sand bodies of subaerial and subaqueous distributary channel,natural levee, flood fan and delta front, and shore-shallow lake environment and lake flow transformation effects that result in the development of sandy beach bar, sheet sand and other sand bodies. Chang 9 sand body mainly developed five basic vertical structures, namely box shape, campaniform, infundibuliform, finger and dentoid. The vertical stacking patterns of multilayer sand body was complex, and the common shapes included box shape + box shape, campaniform + campaniform, campaniform + box shape, infundibuliform + infundibuliform, campaniform + infundibuliform, box shape + campaniform, box shape + infundibuliform,and finger + finger. Based on the analysis on major dominating factors of vertical structure of sand body, sedimentary environment,sedimentary facies and rise, fall and cycle of base level are identified as the major geological factors that control the vertical structure of single sand body as well as vertical stacking patterns and distribution of multistory sand bodies. 展开更多
关键词 vertical structure stacking pattern sand body Chang 9 time Ordos Basin
下载PDF
Experimental study on the degree and damage-control mechanisms of fuzzy-ball-induced damage in single and multi-layer commingled tight reservoirs 被引量:2
8
作者 Chinedu J.Okere James J.Sheng +3 位作者 Li-Kun Fan Xiao-Wei Huang Li-Hui Zheng Pan-Feng Wei 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3598-3609,共12页
Fuzzy-ball working fluids(FBWFs)have been successfully applied in different development phases of tight reservoirs.Field reports revealed that FBWFs satisfactorily met all the operational and reservoir damage control ... Fuzzy-ball working fluids(FBWFs)have been successfully applied in different development phases of tight reservoirs.Field reports revealed that FBWFs satisfactorily met all the operational and reservoir damage control requirements during their application.However,the damage-control mechanisms and degree of formation damage caused by fuzzy-ball fluids have not been investigated in lab-scale studies so far.In this study,the degree of fuzzy-ball-induced damage in single-and double-layer reservoirs was evaluated through core flooding experiments that were based on permeability and flow rate indexes.Additionally,its damage mechanisms were observed via scanning electron microscope and energy-dispersive spectroscopy tests.The results show that:(1)For single-layer reservoirs,the FBWF induced weak damage on coals and medium-to-weak damage on sandstones,and the difference of the damage in permeability or flow rate index on coals and sandstones is below 1%.Moreover,the minimum permeability recovery rate was above 66%.(2)For double-layer commingled reservoirs,the flow rate index revealed weak damage and the overall damage in double-layer was lower than the single-layer reservoirs.(3)There is no significant alteration in the microscopic structure of fuzzy-ball saturated cores with no evidence of fines migration.The dissolution of lead and sulfur occurred in coal samples,while tellurium in sandstone,aluminum,and magnesium in carbonate.However,the precipitation of aluminum,magnesium,and sodium occurred in sandstone but no precipitates found in coal and carbonate.The temporal plugging and dispersion characteristics of the FBWFs enable the generation of reservoir protection layers that will minimize formation damage due to solid and fluid invasion. 展开更多
关键词 DRILLING Fracture Fuzzy-ball fluids Formation damage analysis Muti-layer tight reservoirs Permeability damage index Flow rate damage index
下载PDF
Pore throat structure heterogeneity and its effect on gas-phase seepage capacity in tight sandstone reservoirs:A case study from the Triassic Yanchang Formation,Ordos Basin 被引量:1
9
作者 Yu-Bin Yang Wen-Lian Xiao +8 位作者 Ling-Li Zheng Qi-Hong Lei Chao-Zhong Qin You-An He Shuai-Shuai Liu Min Li Yong-Ming Li Jin-Zhou Zhao Meng Chen 《Petroleum Science》 SCIE EI CSCD 2023年第5期2892-2907,共16页
The microscopic heterogeneity of pore-throat structures in tight sandstone is a crucial parameter for understanding the transport mechanism of fluid flow.In this work,we firstly developed the new procedure to characte... The microscopic heterogeneity of pore-throat structures in tight sandstone is a crucial parameter for understanding the transport mechanism of fluid flow.In this work,we firstly developed the new procedure to characterize the pore size distribution(PSD)and throat size distribution(TSD)by combining the nuclear magnetic resonance(NMR),cast thin section(CTS),and constant-rate mercury injection(CRMI)tests,and used the permeability estimated model to verify the full-scale PSD and TSD.Then,we respectively analyzed the fractal feature of the pore and throat,and characterized the heterogeneity of pores and throats.Finally,we elaborated the effect of the pore and throat heterogeneity on the gas-phase seepage capacity base on the analysis of the simple capillary tube model and gas-flooding experiment.The results showed that(1)The PSD and TSD of the tight sandstone sample ranged from 0.01 to 10 mm and from 0.1 to 57 mm,respectively,mainly contributed by the micropores and mesopores.Meanwhile,the permeability estimated by the PSD and TSD was consistent with the experimental permeability,and relative error was lower than 8%.(2)The PSD and TSD exhibited multifractal characteristics,and singularity strength range,Δα,could be used as the indicator for characterizing the heterogeneity of pore and throat.Furthermore,the throat of the sample showed stronger heterogeneity than that the pore.(3)The throats played an important role for the fluid transport in the tight sandstone,and the effect of the throat heterogeneity on the gas-phase seepage capacity was different under the lower and higher injection pressure.The macropores and micropores maybe respectively become the preferential migration pathways at the lower and higher injection pressure.In the end,the identification plate was established in our paper,and could be described the relationship among the throat heterogeneity,injection pressure,permeability and flow path of the gas phase in the tight sandstone. 展开更多
关键词 Tight sandstone Pore size distribution(PSD) Throat size distribution(TSD) Pore and throat heterogeneity Gas-phase flow capacity Nuclear magnetic resonance(NMR) Constant-rate mercury injection(CRMI)
下载PDF
Clastic compaction unit classification based on clay content and integrated compaction recovery using well and seismic data 被引量:1
10
作者 Zhong Hong Ming-Jun Su +1 位作者 Hua-Qing Liu Gai Gao 《Petroleum Science》 SCIE CAS CSCD 2016年第4期685-697,共13页
Compaction correction is a key part of paleogeomorphic recovery methods. Yet, the influence of lithology on the porosity evolution is not usually taken into account. Present methods merely classify the lithologies as ... Compaction correction is a key part of paleogeomorphic recovery methods. Yet, the influence of lithology on the porosity evolution is not usually taken into account. Present methods merely classify the lithologies as sandstone and mudstone to undertake separate porositydepth compaction modeling. However, using just two lithologies is an oversimplification that cannot represent the compaction history. In such schemes, the precision of the compaction recovery is inadequate. To improve the precision of compaction recovery, a depth compaction model has been proposed that involves both porosity and clay content. A clastic lithological compaction unit classification method, based on clay content, has been designed to identify lithological boundaries and establish sets of compaction units. Also, on the basis of the clastic compaction unit classification, two methods of compaction recovery that integrate well and seismic data are employed to extrapolate well-based compaction information outward along seismic lines and recover the paleo-topography of the clastic strata in the region. The examples presented here show that a better understanding of paleo-geomorphology can be gained by applying the proposed compaction recovery technology. 展开更多
关键词 Compaction recovery Porosity-clay contentdepth compaction model Classification of lithological compaction unit Well and seismic data integrated compaction recovery technology
下载PDF
Chemical Characteristics of Cr-spinel of Chromites in Kuda Ophiolite of Western Kunlun and Its Geological Implications
11
作者 QIAO Gengbiao WANG Ping ZHAO Xiaojian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期192-,共1页
The Kuda ophiolite belongs to the early Paleozoic ophiolite belt in Western Kunlun Mountains and is composed of metamorphic peridotites,cumulate peridotites,mafic volcanic rocks and quartzites(Li et al.,
关键词 Chemical Characteristics of Cr-spinel of Chromites in Kuda Ophiolite of Western Kunlun and Its Geological Implications Cr
下载PDF
The Ocean Redox State Evolution and Its Controls during the Cambrian Series 1–2: Evidence from Lijiatuo Section, South China 被引量:1
12
作者 Lei Xiang Chunfang Cai +5 位作者 Xunyun He Lei Jiang Yuyang Yuan Tiankai Wang Lianqi Jia Lei Yu 《Journal of Earth Science》 SCIE CAS CSCD 2016年第2期255-270,共16页
Well-exposed Lijiatuo Section was chosen to explore the temporal evolution and controls of the oceanic redox state, primary productivity and seawater sulfate levels during the Cambrian Series 1-2, South China. This se... Well-exposed Lijiatuo Section was chosen to explore the temporal evolution and controls of the oceanic redox state, primary productivity and seawater sulfate levels during the Cambrian Series 1-2, South China. This section consists of Xiaoyanxi Formation(Fm.) mudstones and Liuchapo Fm. cherts that deposited in the slope and basin environment. Five oxic-anoxic cycles were identified based on V/Sc, Th/U and the enrichment factors of Mo, U, V, Ni and Cu. The Middle-Upper Liuchapo Fm. and the Middle Xiaoyanxi Fm. were deposited under oxic-suboxic conditions, and the rest of the strata were under anoxic conditions. The Re/Mo ratio demonstrated that the oxic-suboxic conditions in the Middle Xiaoyanxi Fm. were accompanied by transient sulfidic conditions, and the rest of the section was underanoxic and non-sulfidic conditions. All the TOC and the enrichment factors of Ba, Ni, Cu, Zn and Cd demonstrated that both the sinking and burial flux of organic matter(OM) in Liuchapo Fm. were lower than that in the overlying Xiaoyanxi Fm. The highest sinking and burial flux of OM in the Xiaoyanxi Fm. appeared at its lower parts; however, the lowest sinking and burial flux of OM in the Xiaoyanxi Fm. appeared in its middle parts. TOC/TS, TS and the vertical trend of δ^(34)S_(py) demonstrated that the seawater was dominated by low oceanic sulfate levels, which resulted in the absence of free H_2S. The rise of the atmospheric oxygen content may be the principal driver for the associated, transient suboxic-oxic and nearly sulfidic environment in the middle Xiaoyanxi Fm. 展开更多
关键词 trace element redox state seawater sulfate level Cambrian Series 1-2 South China.
原文传递
Zircon SHRIMP U-Pb age and geological implications of tuff at the bottom of Chang-7 Member of Yanchang Formation in the Ordos Basin 被引量:14
13
作者 WANG DuoYun XIN BuShe +3 位作者 YANG Hua FU JinHua YAO JinLi ZHANG Yu 《Science China Earth Sciences》 SCIE EI CAS 2014年第12期2966-2977,共12页
A table tuff interlayer at the bottom of Chang-7 Member of Yanchang Formation,the Ordos Basin,may serve as an indicator for stratigraphic division and correlation.In this study,zircon SHRIMP U-Pb dating was performed ... A table tuff interlayer at the bottom of Chang-7 Member of Yanchang Formation,the Ordos Basin,may serve as an indicator for stratigraphic division and correlation.In this study,zircon SHRIMP U-Pb dating was performed on the tuff at the bottom of Chang-7 Member using samples from wells Luo-36 and Zhuang-211 in the southwest of the basin,which yielded weighted average 206Pb/238U ages of 241.3±2.4 and 239.7±1.7 Ma,respectively.The cathodoluminescence images and the U/Th element ratio of tuff indicate that the zircons are magmatogenic and their ages represent that of the sedimentation age of the tuff at the bottom of Chang-7,which is 239.7–241.3 Ma in age.This finding confirms presence of the Middle Triassic strata at the bottom of Yanchang Formation.Taking previous findings into account,we suggest restricing the Late Triassic Yanchang Formation sensu stricto to the interval from Chang-7 to Chang-1 and assigning the interval from Chang-10 to Chang-8 as the Tongchuan Formation.The tuff at the bottom of the Chang-7 Member of Yanchang Formation represents the sedimentary response to the Qinling orogenic event in the early Indosinian.This tectonic event resulted in major changes in paleogeomorphology and the sedimentary environment of the lake basin during deposition of the Yanchang Formation.During this period,extremely favourable conditions were present for subsequent hydrocarbon generation and pooling of lake basin. 展开更多
关键词 Ordos Basin Yanchang Formation TUFF SHRIMP U-Pb dating geological implications
原文传递
Sulige Gas Field super project
14
作者 Wenrui HU Jingwei BAO Pengcheng JI 《Frontiers of Engineering Management》 2017年第3期379-384,共6页
Owner:Petro China Changqing Oilfield Company Design unit:Petro China Changqing Oilfield Company Construction unit:Petro China Changqing Oilfield Company,CNPC Chuanqing Drilling Engineering Company Limited,CNPC Greatwa... Owner:Petro China Changqing Oilfield Company Design unit:Petro China Changqing Oilfield Company Construction unit:Petro China Changqing Oilfield Company,CNPC Chuanqing Drilling Engineering Company Limited,CNPC Greatwall Drilling Company。 展开更多
关键词 Sulige Gas Field super project
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部