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01 January 2019, Volume 39 Issue 4 Previous Issue    Next Issue

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Geochemical Features and Geological Significance of Oil Seepages in Northeastern Wulungu Depression WANG Qianjun1, CAO Gaoshe2,3, XING Zhou2, WANG Jinduo1 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180401 Abstract ( 116 )   PDF (300KB) ( 160 )   Save Exploration breakthrough has not been achieved in Wulungu depression in the northeastern margin of Junggar basin, this should be attributed to the absence of Permian source rock which is commonly found in Junggar basin. Although the Carboniferous basement of Wulungu depression is considered as the most likely potential source rock, it is still doubtful whether reservoirs can form here. Flame-like, disseminated and dendritic solid bitumen seepages which intrude into the earthy yellow, unconsolidated sand sediments and weathering granites of Quaternary are found in the outcrops of northeastern Wulungu depression. On the basis of the analysis of total organic carbon content, rock pyrolysis, chloroform bitumen A, vitrinite reflectance, carbon isotope of kerogen and biomarkers of steriod and terpenoid, the paper verifies the presence of the oil seepages and compares them with the source rocks and discoverded crude oil in the study area. The study shows that the oil seepages have high total organic carbon contents which indicate typical carbon isotope values of coal formed oil and the oil source is the Carboniferous black mudstone distributed in the oil seepage area; this oil is greatly different from the oil sourced from Permian, Middle—Upper Triassic and Jurassic rocks in Zhundong area, but it can be well correlated with the Carboniferous oil. The regional structural analysis indicates that the basement of Wulungu depression is a part of Central Asia Orogenic Belt, which has similar compositions and structural features with the Carboniferous strata in the areas where the oil seepages are located. Therefore, the discovery and study of the oil seepages not only have important significance for oil and gas exploration in the study area, but can provide references for oil and gas exploration in Wulugu depression in the northeastern margin of Junggar basin Related Articles | Metrics

Organic Facies and Hydrocarbon Generation Characteristics of Lower Cretaceous Source Rocks in Northeastern Erlian Basin CHENG Zhiqiang1, WANG Feiyu1, JIANG Tao2, REN Libing1, WU Ziqiang1, XIE Hong3 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180402 Abstract ( 60 )   PDF (300KB) ( 149 )   Save Bayindulan sag and Wuliyasitai sag are located in the northeastern Erlian basin with only 30 km apart. However, there are great differences in organic facies between the source rocks of the two sags. The source rock of Bayindulan sag is dominated by organic facies C with the initial hydrogen index ranging from 400 to 800 mg/g, averaging 600 mg/g, and the source rock was formed in a brackish to fresh water, reduction environment with the organic maceral dominated by sapropelinite. The source rock of Wuliyasitai sag is dominated by organic facies D/E with the initial hydrogen index ranging from 200 to 400 mg/g, averaging 333 mg/g and the source rock was formed in a fresh water, oxidation environment with the organic maceral dominated by sapropelinite, exinite and vitrinite. The organic facies of source rocks can determine hydrocarbon generation characteristics. The hydrocarbon generation features of the source rocks in the 2 sags are significantly different. The crude oil of Bayindulan sag has relatively high sulfur content and asphaltenes plus resin content with the API of 15°~30°; while the API for the crude oil of Wuliyasitai sag ranges from 35° to 45° and the oil is classified as light oil. The differences of organic facies of source rocks will result in the differences of hydrocarbon generation threshold. The source rock maturity of the southern subsag of Wuliyasitai sag is higher than that of Bayindulan sag; and the threshold depth of hydrocarbon generation in Bayindulan sag is 1 500~1 600 m, whereas that of the southern subsag of Wuliyasitai sag is 1 900~2 000 m, which is deeper than those of other hydrocarbon-rich sags in Erlian basin. There are significantly different hydrocarbon generation characteristics between the source rocks of organic facies D/E and typical organic facies C (dominated by lamalginite and telalginite), the source rock of the organic facies D/E has higher hydrocarbon generation and expulsion temperatures and mainly expels light oil Related Articles | Metrics

Sedimentary Characteristics and Its Main Controlling Factors of the Late Jurassic Shallow-Water Delta in Western Sichuan Depression LIU Junlong1,2, SUN Dongsheng1, JI Youliang2, YIN Wei1, YU Haiyue2, WANG Tianyun3 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180403 Abstract ( 59 )   PDF (300KB) ( 132 )   Save Taking the Late Jurassic shallow-water deltas developed in the foreland basin of western Sichuan area as cases and using integrated geological data of seismic profiles and well logs, the paper clarifies the sedimentary characteristics and its controls of the shallow-water deltas. The results show that the shallow-water delta systems in the foreland basin of western Sichuan are characterized by “coexistence of provenances along the long axis and short axis”, furthermore, during different depositional periods the supply capacity of the provenance were different along the long and short axises; the shallow-water deltas are mainly controlled by auto-cycle and allo-cycle, among which the control of episodic tectonic uplift on the shallow-water deltas is the main feature to distinguish depression basin and rifted basin. The study perfects the application of shallow-water delta theory in lacustrine basins and provides references for the studies on shallow-water delta developed in other foreland basins Related Articles | Metrics

Characteristics and Hydrocarbon Accumulation Models of Carboniferous Inside-Type Volcanic Reservoir in Xiquan Area, Junggar Basin FAN Guangxu1,2a, ZHU Ka2b, WANG Libing2b, CHEN Hong2b, LI Hui2b 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180404 Abstract ( 88 )   PDF (300KB) ( 290 )   Save The strong heterogeneity, unclear controlling factors and reservoir accumulation rules of the Carboniferous inside-type volcanic reservoir constrain its exploration in Xiquan area of eastern Junggar basin. Based on the data of geophysical prospecting, geology and drilling, the paper studies the characteristics of the Carboniferous inside-type volcanic reservoir in Xiquan area. The inside-type volcanic reservoir in the study area is characterized by low porosity, low permeability and strong heterogeneity, which belongs to fracture-pore reservoirs. The study shows that lithology and lithofacies are the basis for high-quality reservoir forming, the development degree of fractures is an important factor affecting the physical property and effectiveness of the reservoir, and dissolution can improve the physical properties of the Carboniferous inside-type volcanic reservoir. Based on the configuration relationships between hydrocarbon source rocks and reservoirs, 3 hydrocarbon accumulation models of the Carboniferous volcanic rocks in the study area are established—the reservoir of weathering crust type is mainly developed in Batamayineishan formation; 2 kinds of inside-type gas reservoirs are found in Songkaersu formation, i.e., the lithological gas reservoirs in the b member of Songkaersu formation and the structural oil and gas reservoirs in the a member of Songkaersu formation. The shallow Carboniferous strata with high exploration degree are the areas where oil reservoirs are developed, and the deep slope zones are the favorable areas for natural gas exploration which has good prospecting potential and low exploration degree Related Articles | Metrics

Mineralogical Characteristics of Paleozoic Marine Shales in Well W201 of Weiyuan Area, Southern Sichuan Basin TIAN Xingwang1, HU Guoyi2, SU Guiping3, SUN Yiting1, Hong Haitao1, SHAN Shujiao1 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180405 Abstract ( 144 )   PDF (300KB) ( 264 )   Save The study on mineralogical characteristics of shales is an integral part of shale gas reservoir research, which lays an important foundation for the research on fracture evaluation, seepage flow migration and fracturing and so on. Using X ray diffraction (XRD) analysis technique, the paper qualitatively and quantitatively analyzes the mineral compositions of core samples obtained from 2 sets of marine shales of the Lower Cambrian Qiongzhusi formation and Lower Silurian Longmaxi formation in Well W201 of Weiyuan area, southern Sichuan basin. The results show that the minerals of the 2 sets of marine shales in Weiyuan area of the southern Sichuan basin are mainly composed of clay, quartz, carbonate and a few pyrites. The quartz contents of the marine shale samples from Qiongzhusi formation and Longmaxi formation are 38.7% and 31.8%, respectively, and the clay contents of the 2 formations are 26.1% and 37.3%, respectively. The shales were formed in a marine strong-reduction depositional environment which was good for the enrichment and preservation of organic matters and could provide good conditions for shale gas generation. Brittle mineral contents of the 2 formations are relatively high with the averages of 70.5% and 58.7%, respectively and the brittleness indexes of 73.0% and 61.1%, respectively, which indicates that the 2 formations have good brittleness and fracability. Both Qiongzhusi formation and Longmaxi formation are the key target zones for shale gas exploration Related Articles | Metrics

Quantitative Characterization of Organic Matters with Different Occurrences in Argillaceous Source Rocks: A Case of Shahejie Formation, Dongying Sag ZHAO Yue1,2, CAI Jingong2, LEI Tianzhu3, YANG Yan3,4 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180406 Abstract ( 93 )   PDF (300KB) ( 172 )   Save The organic matters retained in argillaceous source rocks are of various occurrences, including free state and mineral-binding state organic matters which have quite different geochemical natures and different significance in detailed source rock evaluation. However, a comprehensive quantitative characterization technique for both occurrences has not been established yet. With the argillaceous source rocks sampled from the middle Es3, the lower Es3 and the upper Es4 of the Shahejie formation, Dongying sag, and based on the analysis on the changes of pyrolysis parameters during the processes of solvent extraction and sequential chemical treatment including the variations of free hydrocarbon, cracked hydrocarbon and TOC, the paper measures the abundance of the organic matters with different occurrences quantitatively and establishes a quantitative characterization method of retained organic matters with different occurrences. The results show that the quantity of soluble organic matters of mineral-binding state is quite large in the organic matters retained in source rocks. Traditional evaluation methods such as Rock-Eval pyrolysis method and chloroform bitumen A method have some limitations. Profound study on the geochemical characteristics of the organic matters of mineral-binding state will widen the knowledge of hydrocarbon generation theory and retained hydrocarbon occurrences Related Articles | Metrics

Characteristics of Fractures in Xujiahe Formation of Tongnanba Structural Belt, Northeastern Sichuan Basin CAO Huanyu, WANG Wei, LIU Ming 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180407 Abstract ( 87 )   PDF (300KB) ( 324 )   Save In order to study the characteristics of fractures in the tight sandstone reservoirs and their influences on natural gas accumulation, taking Tongnanba structural belt as a case, the paper comprehensively studies the fracture development characteristics in Xujiahe formation in the study area by using the data of core, thin section and FMI logging. According to fracture genesis, the fractures in the tight sandstone reservoir of Xujiahe formation can be classified into 4 types, namely fault-associated fracture, fold-associated fracture, sliding fracture and gravel-associated fracture, among which fault-associated and fold-associated fractures are the main effective fractures. Good correlations among the development of effective fractures, lithology, fault and local structures are found in the study area. Fractures are most developed in the fine sandstones and medium-sized sandstones, and high-curvature anticline and large fracture are favorable conditions for fracture development in the study area. Fracture development in the tight sandstone reservoir of Xujiahe formation was controlled by orogenic activities in the basin margin since Late Jurassic during which the reservoir of Xujiahe formation was densified and the development of fractures improved the reservoir quality and permeability which had important significance for accumulation and high-yield of the gas reservoirs formed at the late stage Related Articles | Metrics

Diagenesis and Pore Evolution of Tight Sandstone Reservoir of Chang 61 Member in Jiyuan Area, Ordos Basin WANG Bin1, SUN Wei1, BAI Yunyun1,2, HAN Jin1,3, LIU Dengke1, ZHANG Xi1 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180408 Abstract ( 74 )   PDF (300KB) ( 41 )   Save Based on the data of cast thin section, scanning electron microscopy(SEM), X-ray diffraction and physical property analysis, the paper studies the features of petrology and diagenetic process and their influences on reservoir pore evolution of Chang 61 tight sandstone reservoir in Jiyuan area, Ordos basin. The results show that the tight sandstone reservoir in the study area experienced a complicated diagenetic process and most of the reservoir has entered phase A of the middle diagenetic stage and the rest has been in the early phase B of the middle diagenetic stage. Based on the establishment of quantitative porosity evolution model, it is found that compaction is the main factor causing the reservoir densification which results in the decrease of the reservoir porosity by 21.52% with the porosity loss rate of 55.72%; cementation damage on reservoir is the secondary with the porosity loss rate of 32.41%; dissolution can increase the porosity by the average of 4.36%. Using burial history to match comprehensive porosity evolution history, the paper characterizes the influences of burial depth and diagenesis on porosity quantitatively. The analysis on 4 typical samples further indicates that the Chang 61 tight sandstone reservoir in the study area belongs to compaction-type diagenesis, and compaction and cementation are the key factors causing reservoir densification Related Articles | Metrics

Coupling Relationship between Reservoir Densification and Natural Gas Accumulation in Shaximiao Formation in Western Sichuan Depression NAN Hongli, CAI Limei, YE Sujuan, YAN Lini, ZHANG Shihua, YANG Yingtao 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180409 Abstract ( 54 )   PDF (300KB) ( 100 )   Save Based on the observation under microscope and the analysis on the data of SEM, electronic probe, isotopes of carbon and oxygen in carbonate cements, and combined with the burial history and structural evolution history, the paper identifies the diagenesis and reservoir space types and establishes diagenetic evolution sequences for different types of reservoirs of the Middle Jurassic Shaximiao formation in the western Sichuan depression. The study shows that different reservoirs have different accumulation characteristics and diagenetic evolutions. Compaction acted as the main destructive effect for the pores in far-from-provenance, feldspar-rich reservoirs whose reservoir spaces were dominated by feldspar-dissolved secondary pores and the reservoir densification time was late; compaction and cementation acted as the main destructive effects for the pores in near-provenance, debris-rich reservoirs whose reservoir spaces were dominated by residual intergranular pores and the densification time of this kind of reservoir was relatively early. The analysis on phase, occurrence and homogeneous temperature of inclusion indicates that the Middle Jurassic gas reservoirs are featured with multiple periods of hydrocarbon charging. The coupling relationship between reservoir densification and hydrocarbon accumulation reflects that the far-from-provenance, feldspar-rich reservoirs have a feature of hydrocarbon accumulation and reservoir forming simultaneously and the near-provenance, debris-rich reservoirs is characterized by densification before reservoir forming Related Articles | Metrics

Architecture Analysis and Remaining Oil Distribution in Mouth Bar: A Case Study of the First Member of Xishanyao Formation in Wellblock Cai-10 and Caican-2, Cainan Oilfield YIN Senlin1, ZHANG Tong2, WAN Wensheng2, WU Chengmei2, LI Chen2, FENG Wenjie3 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180410 Abstract ( 91 )   PDF (300KB) ( 137 )   Save To study the inner architecture and remaining oil distribution in the mouth bar of meandering river delta, based on the production performance and core data in the Wellblock Cai-10 and Caican-2 of Cainan oilfield, the paper performs detailed analysis on the mouth bar architecture by using the methods of analytical hierarchy process, multi-dimensional interaction and dynamic verification, and establishes mouth bar architecture models for the meandering river delta in the study area. The study shows that there are 2 categories of marks to identify single mouth bar boundary, namely vertical superposition of the units of different periods and lateral merging of the units of same periods, among which the latter structure can be classified into 3 types such as main body—main body of the mouth bar, main body—bar margin—main body and main body—between-bar mud. There are 2 mouth bar architecture models such as progradation and accretion. The progradational architecture model mainly refers to the structures in which the sediments of late stage accreted and superposed onto the mouth bars of early stage when the distributary channel was under the circumstance of stable hydrodynamic force, and the lateral accretional architecture model mainly refers to the mouth bars which are developed at the margin of breached distributary channel when the hydrodynamic force became stronger. In the study area, there are 129 single mouth bars and 12~24 mouth bars that are developed in the single layers. The single mouth bars are about 500 m long and 450 m wide. The dip angle of accretional architecture mouth bar is 0.31°~2.40°, which decreases from bottom to top. The remaining oil distribution can be divided into 4 patterns, namely retention, one-way effect, poor water injection effect and planar interference patterns. Various development programs and measures can be adopted to enhance oil recovery Related Articles | Metrics

A Multifactorial Material Balance Equation for Shale Gas Reservoirs MEI Haiyan1, HE Lang1, ZHANG Maolin1,2, HU Xinrui1, Mao Hengbo1 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180411 Abstract ( 87 )   PDF (300KB) ( 208 )   Save Shale gas is consisted of free gas, adsorbed gas and dissolved gas. In practical shale gas reservoirs, not only methane is adsorbed, but also other gases such as ethane and propane are parts of the adsorbed gas. Therefore, it is necessary to take multi-component adsorption into consideration when calculating the amount of adsorbed gas. Moreover, some scholars have found that a large amount of shale gas is also dissolved in kerogen, which can not be ignored in the evaluation of shale gas reserves. The paper considers the free gas in fractures, the porosity and volume of adsorbed phase, critical desorption pressure of adsorbed gas and shrinkage distortion of rock matrix caused by the desorption of adsorbed gas, modifies the compressibility of rock, takes multi-component adsorption and dissolved gas into consideration and establishes a new multifactorial material balance equation for shale gas reservoir. The case shows that when considering multi-component adsorption, the calculated free gas reserves basically keeps unchanged, the adsorbed gas reserves increases by 0.308 1×108m3, the total reserves increases by 0.259 5×108m3 (equivalent to 10.97% of the total reserves), and the dissolved gas accounts for 6.58% of the total reserves; considering dissolved gas will lead to a decline in the percentages of reserves of free gas and adsorbed gas, which has a little impact on the total reserves of shale gas reservoirs. In order to understand the dynamic reserves of shale gas reservoirs more accurately, multi-component adsorption and dissolved gas need to be considered simultaneously Related Articles | Metrics

Development Potential of Undeveloped Reserves of Low-Permeability Conglomerate Reservoirs, Junggar Basin PAN Honga, YANG Zuomingb, WANG Jinhuia, LUOGuanxinga, ZHANG Yia, XUE Yuanb 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180412 Abstract ( 72 )   PDF (300KB) ( 125 )   Save Combining the data of geology and exploitation, the paper systematically evaluates the development effects of low-permeability conglomerate reservoirs in Xinjiang oilfield. Through the analysis of the development effect scores given by experts for developed blocks and the basic evaluation parameters, the key parameters which can characterize the development effects are determined as reserves abundance, air permeability, daily oil production per kilometer in depth and oil viscosity. Multivariate linear regression has been performed for these parameters and development effect scores given by experts, and a comprehensive model has been established for development potential evaluation. Based on which, combining with the strategic factor analysis, the paper builds evaluation charts for reservoir geology factors and economic environment factors. Taking the internal rate of return greater than 8% and the comprehensive score higher than 72 as criteria, respectively, 6 blocks including JL-2, B-34, M-2, JW-42, W-109 and 531 are selected as the mid-term development targets. Taking the internal rate of return greater than 12% and the comprehensive score higher than 78 as criteria, respectively, 3 blocks such as M-18, X-54 and X-50 are selected as the short-term development targets, which can provide basis for development decision making Related Articles | Metrics

Analysis of Micropore Structure and Movable Fluid Saturation Characteristics of Dengying Formation in GaoshitiMoxi Area of Central Sichuan Basin REN Cong1, LI Yong2, ZHAO Xiaohong1, CHEN Wei1, WANG Shuyan1, LI Juzheng1 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180413 Abstract ( 88 )   PDF (300KB) ( 109 )   Save The micropore structure of the reservoir of Dengying formation in Gaoshiti—Moxi area of central Sichuan basin is complicated. Weak study on movable fluid is the key factor constraining further EOR in the area. Using analysis means such as cast thin section, SEM, high pressure mercury injection and NMR etc., the paper studies the type and structure of the micropores in the 4th member of Dengying formation in the study area, and analyzes the relationship between movable fluid saturation and micropore structure. The results show that the accumulation spaces in the study area are dominated by intergranular dissolved pore, residual intergranular pore, intercrystalline pore and dissolved cave with the average total surface porosity of 2.5%; various pore combinations have different micropore structures, among which the pore structures of the reservoir dominated by intergranular dissolved pore–residual intergranular pore are the best, and the displacement pressure and median pressure are 4.1 MPa and 18.7 MPa, respectively, which are relatively low. The average pore throat radius is 0.059 μm and the movable fluid saturation is relatively high, which is 41.5%. The permeability and the development degree of intergranular dissolved pore are the key factors influencing movable fluid saturation which shows a positive correlation with radius and connectivity of pore throat Related Articles | Metrics

Visualized Gas Drive EOR Experiments in Fractured-Vuggy Reservoirs after Waterflooding in Tahe Oilfield CHENG Xiaojun 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180414 Abstract ( 54 )   PDF (300KB) ( 116 )   Save Gas injection EOR experiments are carried out in single wells after waterflooding development in fractured-vuggy reservoirs in Tahe oilfield and good results have been gained. But the effects of waterflooding and gas injection in single wells are becoming worse at the middle-late development stage, causing large amounts of remaining oil can’t be produced after waterflooding. To improve the development effects of gas injection in this kind of reservoirs, the study on the mechanism of gas injection EOR in multiple wells needs to be carried out. Through gas drive simulation experiments on the basis of visualized models, the paper discusses the remaining oil distribution and its influencing factors after gas drive in fractured-vuggy reservoirs. The experiment results show that N2 flooding after waterflooding can effectively improve oil displace efficiency, and gas injection mode, injection point and model filling can influence the gas drive effects; gas drive effects can be improved by using continuous and stable gas injection, and gas injection at high positions of structures and producing oil at low positions of structures, which can provide basis for remaining oil production in similar reservoirs after waterflooding Related Articles | Metrics

Integrated Geology-Engineering Development Technology for Fractured Tight Oil Reservoirs HOU Bing1, LIU Qing2, GENG Zhi1, SHENG Shifeng2 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180415 Abstract ( 103 )   PDF (300KB) ( 147 )   Save Taking the fractured tight igneous rock reservoirs of Fengcheng formation in Wellblock Ke-80, Karamay oilfield as a case, integrated geology-engineering development technology is proposed to improve well productivity. Based on effective identification of potential areas for natural fractures in the reservoir, the paper accurately predicts the regional ground stress and strength of 3D reservoir rock mechanics, establishes a feasibility evaluation method of regional fracturing and optimizes sweet-spots for fracturing. Based on which productivity modeling and fracturing program optimization are carried out for target well locations and the final engineering program can be determined. The actual drilling results show that the integrated geology-engineering development technology can effectively improve the connecting scale of fracture network, enlarge the discharge area and then improve the well productivity significantly. Meanwhile, the well productivity is further improved by increasing the hydraulic fracturing fluid volume during secondary fracturing regarding sweet-spot areas. The application effect of the technology has proved its availability and promotional value, which has significance for effective development of fractured tight oil reservoirs Related Articles | Metrics

Effects of CO2 Huff and Puff in Horizontal Wells in Shallow-Burial Thin Heavy Oil Reservoirs ZHANG Juan1, ZHOU Lifa1, ZHANG Xiaohui2, ZHANG Maolin3, FAN Jin4, DU Hongbao4 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180416 Abstract ( 125 )   PDF (300KB) ( 288 )   Save The paper uses the 2 indexes of accumulative oil increment and oil exchange ratio to evaluate the field test effects of CO2 huff and puff in 7 typical horizontal wells in G block of Jidong oilfield, performs the production history matching through numerical simulation and studies the mechanism of CO2 huff and puff EOR and its main influence factors by combining with geological and engineering parameters. The study results show that the higher the oil saturation around horizontal wells, the better the EOR effects by CO2 huff and puff in horizontal wells; the longer the horizontal section of horizontal wells, the longer the perforated intervals, the larger the laterally swept areas of CO2, and the less of CO2 consumption in bottom-water layer, the better huff and puff effect will be gained. During CO2 huff and puff, CO2 is not only dissolved in the oil, but also can drive the oil away from the well bottom under the injection pressure, which could result in the effects of adjacent wells. After CO2 huff and puff, the oil saturation around the horizontal well bottom drops dramatically and a cavity will form, which can influence the effect of next cycle of CO2 huff and puff Related Articles | Metrics

The Status and Prospects of Research on Characterization for Sandy Braided-River Reservoir Architecture MAO Ping 2018, 39 (4):  1-1.  doi: 10.7657/XJPG20180417 Abstract ( 87 )   PDF (300KB) ( 216 )   Save The characterization of reservoir architecture is an important method to study genesis and spatial distribution of sedimentary units, which is of great significance for efficient reservoir development. Since the concept of reservoir architecture was proposed by Miall in 1985, many good results have been achieved in the field of sandy braided-river reservoir study in China and abroad. It is necessary to systematically summarize the progresses on the study of sandy braided-river reservoir architecture characterization. In terms of 4 aspects such as sandy braided-river reservoir architecture model, architecture unit scale, underground reservoir architecture characterization technology and the influence of architecture units of different orders on remaining oil distribution, the paper systematically summarizes the research progresses of more than 30 years, and points out the future development trend from the views of architecture model and its application— strengthening the study of sedimentary process, perfecting architecture models of different orders, enhancing discipline integration and realizing effective integration of sedimentary architecture sand body and reservoir performance Related Articles | Metrics