Development and distribution of mound-shoal complex in the Sinian Dengying Formation, Sichuan Basin and its control on reservoirs
Lan Caijun1,2, Xu Zhehang1,2, Ma Xiaolin1,2, Hu Chao1,2, Chen Haoru3, Zou Huayao1,2
1. State Key Laboratory of Petroleum Resources and Prospecting, Beijing 102249, China;
2. College of Geosciences, China University of Petroleum, Beijing 102249, China;
3. Faculty of Earth Resources, China University of Geosciences, Hubei Wuhan 430074, China
The reservoirs of the Sinian Dengying Formation in Sichuan Basin are mainly developed in the microbial mound-shoal complex, but the influence from the complex of different genetic types on reservoirs remains unclear. By means of drilling core and field outcrop observation, thin-section analysis and physical property test, the mound-shoal complex is divided into the mound-base, mound-core, mound-flank and mound-flat microfacies; based on the microfacies assemblage, three types of mound-shoal complexes can be identified as below:platform-margin keep-up mound-shoal, platform-margin catch-up mound-shoal and intra-platform give-up mound-shoal. The growth rate of platform-margin keep-up mound-shoal is fast, synchronous with the growth rate of the accommodation space. The microfacies assemblage of platform-margin keep-up mound-shoal is mainly shown as the vertical accretion of "mound-base+mound-core", which is easy to be exposed to the meteoric fresh water during sea level eustacy, resulting in weak seawater cementation and strong freshwater dissolution, and forming reservoir space dominated by lattice dissolution pores, with good physical property and optimal reservoir performance. The platform-margin catch-up mound-shoal has the second fastest growth rate that lagged behind but gradually synchronized with the rate of accommodation space and presents laterally aggradation of "mound-base + mound-core+mound-flank/mound-flat" in microfacies assemblage. Due to the reduced probability of exposure to meteoric fresh water, the reservoir performance in platform-margin catch-up mound-shoal is quite poor as the result of strong seawater cementation and weakening fresh water dissolution. The intra-platform give-up mound-shoal shows the slowest growth rate, seriously lagging behind that of the accommodation space. Its microfacies assemblage is "dolomitic flat (mound-base)+mound-core+mound-flat", which is difficult to be exposed to the meteoric freshwater, with the weakest freshwater dissolution and the poorest reservoir performance. The paleo-geomorphology of the platform margin has a great influence on the growth rate and controls sedimentary pattern of the mound-shoal complex. The platform margin of steep slope is conducive to the development of platform-margin keep-up mound-shoal, platform-margin catch-up mound-shoal and intra-platform give-up mound-shoal are mainly developed in the platform margin of gentle slope and the highland within the platform, respectively. The Member 4 of Sinian Dengying Formation in the Hujiaba-Langzhong-An'yue area is developed in the platform margin of typical steep slope and is the most favorable facies belt for reservoir development.
兰才俊, 徐哲航, 马肖琳, 胡超, 陈浩如, 邹华耀. 四川盆地震旦系灯影组丘滩体发育分布及对储层的控制[J]. 石油学报, 2019, 40(9): 1069-1084.
Lan Caijun, Xu Zhehang, Ma Xiaolin, Hu Chao, Chen Haoru, Zou Huayao. Development and distribution of mound-shoal complex in the Sinian Dengying Formation, Sichuan Basin and its control on reservoirs[J]. Acta Petrolei Sinica, 2019, 40(9): 1069-1084.
DU Jinhu,WANG Zecheng,ZOU Caineng,et al.Geologic theory and exploration practice of ancient large carbonates gas field[M].Beijing:Petroleum Industry Press,2015.
LIU Shugen,MA Yongsheng,HUANG Wenming,et al.Densification process of Upper Sinian Dengying Formation,Sichuan Basin[J].Natural Gas Geoscience,2007,18(4):485-496.
CHEN Ya'na,SHEN Anjiang,PAN Liyin,et al.Features,origin and distribution of microbial dolomite reservoirs:a case study of 4th Member of Sinian Dengying Formation in Sichuan Basin,SW China[J].Petroleum Exploration and Development,2017,44(5):704-715.
LUO Bing,YANG Yueming,LUO Wenjun,et al.Controlling factors and distribution of reservoir development in Dengying Formation of paleo-uplift in central Sichuan Basin[J].Acta Petrolei Sinica,2015,36(4):416-426.
LUO Beiwei,JIA Chengzao,WEI Guoqi,et al.Characteristics and models of weathering paleo-karst in Upper Sinian,Sichuan Basin[J].Journal of China University of Petroleum:Edition of Natural Science,2015,39(3):8-19.
YANG Wei,WEI Guoqi,ZHAO Rongrong,et al.Characteristics and distribution of karst reservoirs in the Sinian Dengying Fm,Sichuan Basin[J].Natural Gas Industry,2014,34(3):55-60.
ZHU Dongya,JIN Zhijun,SUN Dongsheng,et al.Hydrothermally dolomitized reservoir bed in Sinian Dengying Formation,northern China:an example from central Guizhou uplift[J].Chinese Journal of Geology,2014,49(1):161-175.
SONG Guangyong,LIU Shugen,HUANG Wenming,et al.Characteristics of hydrothermal dolomite of Upper Sinian Dengying Formation in the Dingshan-Lintanchang structural zone,Sichuan Basin,China[J].Journal of Chengdu University of Technology:Science & Technology Edition,2009,36(6):706-715.
SHI Zejin,WANG Yong,TIAN Yaming,et al.Cementation and diagenetic fluid of algal dolomites in the Sinian Dengying Formation in southeastern Sichuan Basin[J].Science China Earth Science,2013,56(2):192-202.
ZHOU Jingao,YAO Genshun,YANG Guang,et al.Genesis mechanism of the Sinian-Cambrian reservoirs in the Anyue gas field,Sichuan Basin[J].Natural Gas Industry,2015,35(1):36-44.
YANG Yu,HUANG Xianping,ZHANG Jian,et al.Features and geologic significances of the top Sinian karst landform before the Cambrian deposition in the Sichuan Basin[J].Natural Gas Industry,2014,34(3):38-43.
DU Jinhu,WANG Zecheng,ZOU Caineng,et al.Discovery of intra-cratonic rift in the Upper Yangtze and its coutrol effect on the formation of Anyue giant gas field[J].Acta Petrolei Sinica,2016,37(1):1-16.
ZOU Caineng,DU Jinhu,XU Chunchun,et al.Formation,distribution,resource potential and discovery of the Sinian-Cambrian giant gas field,Sichuan Basin,SW China[J].Petroleum Exploration and Development,2014,41(3):278-293.
GUO Xusheng,HU Dongfeng,DUAN Jinbao,et al.Rock features and sedimentary environment of the fourth Member of Dengying Formation in Hujiaba section of Ningqiang,northern Sichuan Basin[J].Petroleum Geology and Experiment,2018,40(6):749-756.
ZHOU Jingao,ZHANG Jianyong,DENG Hongying,et al.Lithofacies paleogeography and sedimentary model of Sinian Dengying Fm in the Sichuan Basin[J].Natural Gas Industry,2017,37(1):24-31.
[19]
BURNE R V,MOORE LI S.Microbialites; organosedimentary deposits of benthic microbial communities[J].Palaios,1987,2(3):241-254.
[20]
RIDING R.Classification of microbial carbonates[M]//RIDING R.Calcareous algae and stromatolites.Berlin:Springer Science & Business Media,1991.
[21]
RIDING R.Microbialites,stromatolites,and thrombolites[M]//REITNER J,THIEL V.Encyclopedia of geobiology.Dordrecht:Springer Netherlands,2011:635-654.
LIU Jingjiang,LI Wei,ZHANG Baomin,et al.Sedimentary palaeogeography of the Sinian in Upper Yangtze region[J].Journal of Palaeogeography,2015,17(6):735-753.
[23]
HU Mingyi,GAO Da,WEI Guoqi,et al.Sequence stratigraphy and facies architecture of a mound-shoal-dominated dolomite reservoir in the Late Ediacaran Dengying Formation,central Sichuan Basin,SW China[J].Geological Journal,2019,54(3):1653-1671.
XU Zhehang,LAN Caijun,YANG Weiqiang,et al.Sedimentary and evolutionary characteristics of Sinian Dengying-Formation microbial mound in Sichuan Basin[J].Petroleum Geology & Oilfield Development in Daqing,2018,37(2):15-25.
LI Ling,TAN Xiucheng,ZENG Wei,et al.Development and reservoir significance of mud mounds in Sinian Dengying Formation,Sichuan Basin[J].Petroleum Exploration and Development,2013,40(6):666-673.
SONG Jinmin,LUO Ping,LIU Shugen,et al.The deposition and reservoir characteristics of Dengying Formation in western Sichuan Basin,China[J].Journal of Chengdu University of Technology:Science & Technology Edition,2018,45(1):27-44.
HE Dengfa,LI Desheng,ZHANG Guowei,et al.Formation and evolution of multi-cycle superposed Sichuan Basin,China[J].Chinese Journal of Geology,2011,46(3):589-606.
YU Qian,MU Chuanlong,ZHANG Haiquan,et al.Sedimentary evolution and reservoir distribution of northern Upper Yangtze plate in Sinian-Early Paleozoic[J].Acta Petrologica Sinica,2011,27(3):672-680.
WEI Guoqi,YANG Wei,DU Jinhu,et al.Geological characteristics of the Sinian-Early Cambrian intracratonic rift,Sichuan Basin[J].Natural Gas Industry,2015,35(1):24-35.
ZHOU Jingao,SHEN Anjiang,ZHANG Jianyong,et al.Deyang-Anyue interplatform rift in Sichuan Basin and its direction of exploration in Sinian[J].Marine Origin Petroleum Geology,2018,23(2):1-9.
HUANG Qingyu,HU Suyun,PAN Wenqing,et al.Sedimentary characteristics of intra-platform microbial mounds and their controlling effects on the development of reservoirs:a case study of the Lower Cambrian Xiaoerbulake Fm in the Keping-Bachu area,Tarim Basin[J].Natural Gas Industry,2016,36(6):21-29.
[33]
DUNHAM R J.Classification of carbonate rocks according to depositional textures[G]//HAM W E.Classification of carbonate rocks:a symposium.Tulsa:AAPG Memoir,1962:108-121.
[34]
刘静江,张宝民,周慧,等.灰泥丘系统分类及石油地质特征[M].北京:石油工业出版社,2016.
LIU Jingjiang,ZHANG Baomin,ZHOU Hui,et al.Mud mound systems classification and petroleum geological features[M].Beijing:Petroleum Industry Press,2016.
[35]
KRAUSE F F,SCOTESE C R,NIETO C,et al.Paleozoic stromatactis and zebra carbonate mud-mounds:global abundance and paleogeographic distribution[J].Geology,2004,32(3):181-184.
[36]
张荫本.粘结岩分类及应用[J].石油勘探与开发,1993,20(增刊):194-198.
ZHANG Yinben.A study on the classification of Boundstones and its application[J].Petroleum Exploration and Development,1993,20(S):194-198.
[37]
KENDALL C G S C,BOWEN B,ALSHARHAN A,et al.Eustatic controls on carbonate facies in reservoirs,and seals associated with Mesozoic hydrocaron fields of the Arabian Gulf and the Gulf of Mexico[J].Marine Geology,1991,102(1/4):215-238.
[38]
SOREGHAN G S,DICKINSON W R.Generic types of stratigraphic cycles controlled by eustasy[J].Geology,1994,22(8):759-761.
XING Fengcun,LU Yongchao,GUO Tonglou,et al.Sedimentary texture diversity of different carbonate platform margins and it its significance for petroleum exploration:a case study of carbonate platform margins in Feixianguan period of the Early Triassic,NE Sichuan Basin,China[J].Acta Petrologica Sinica,2017,33(4):1305-1316.
HAO Yi,WANG Yufeng,YANG Xun,et al.On diagenesis of dolostone of the Sinian Dengying Formation,in the Sichuan Basin[J].Acta Geologica Sichuan,2016,36(3):367-371.
[45]
HARWOOD C L,SUMNER D Y.Microbialites of the neoproterozoic beck spring dolomite,Southern California[J].Sedimentology,2011,58(6):1648-1673.
[46]
KAHLE C F.Biosedimentology of a Silurian thrombolite reef with meter-scale growth framework cavities[J].Journal of Sedimentary Research,2001, 71(3):410-422.
WANG Wenzhi,YANG Yueming,WEN Long,et al.A study of sedimentary characteristics of microbial carbonate:a case study of the Sinian Dengying Formation in Gaomo area,Sichuan Basin[J].Geology in China,2016,43(1):306-318.
QIN Zhangjin,LIU Zhiyi,ZHOU Jiling.Reservoir characteristics and controlling factors of Dengying Formation in the Anyue-Moxi area of the central of Sichuan Basin[J].Journal of Northeast Petroleum University,2015,39(6):87-94.
ZHOU Zheng,WANG Xingzhi,XIE Ling,et al.Reservoir features and physical influences of the Sinian Dengying Formation (Sinian) in central Sichuan,China[J].Natural Gas Geoscience,2014,25(5):701-708.
CUI Yongqian,WANG Jianguo,TIAN Jianzhang,et al.Reservoir characteristics and main controlling factors of Cambrian-Ordovician dolomite in the north central part of North China platform[J].Acta Petrolei Sinica,2018,39(8):890-901.
LIU Jianqiang,ZHENG Haofu,LIU Bo,et al.Characteristics and genetic mechanism of the dolomite in the middle Permian Maokou Formation,central Sichuan area[J].Acta Petrolei Sinica,2017,38(4):386-398.
ZHAO Wenzhi,SHEN Anjiang,ZHOU Jingao,et al.Types,characteristics,origin and exploration significance of reef-shoal reservoirs:a case study of Tarim Basin,NW China and Sichuan Basin,SW China[J].Petroleum Exploration and Development,2014,41(3):257-267.
MA Yongsheng,MOU Chuanlong,TAN Qinyin,et al.Reef-bank features of Permian Changxing Formation and Triassic Feixianguan Formation in the Daxian-Xuanhan area,Sichuan province,South China and constraint for the reservoirs of natural gas[J].Earth Science Frontiers,2007,14(1):182-192.
WEI Guoqi,YANG Wei,XIE Wuren,et al.Accumulation modes and exploration domains of Sinian-Cambrian natural gas in Sichuan Basin[J].Acta Petrolei Sinica,2018,39(12):1317-1327.
GUO Tonglou.The characteristics of sedimentation and reservoirs of reef-beach gas fields in carbonate platform margins,northeastern Sichuan Basin[J].Earth Science Frontiers,2011,18(4):201-211.
GUAN Shuwei,WU Lin,REN Rong,et al.Distribution and petroleum prospect of Precambrian rifts in the main cratons,China[J].Acta Petrolei Sinica,2017,38(1):9-22.
GU Zhidong,WANG Zecheng.The discovery of Neoproterozoic extensional structures and its significance for gas exploration in the central Sichuan block,Sichuan Basin,South China[J].Science China:Earth Sciences,2014,57(11):2758-2768.
ZHONG Yong,LI Yalin,ZHANG Xiaobin,et al.Features of extensional structures in pre-Sinian to Cambrian strata,Sichuan Basin,China[J].Journal of Chengdu University of Technology:Science & Technology Edition,2013,40(5):498-510.
SONG Jinmin,LIU Shugen,SUN Wei,et al.Control of Xingkai taphrogenesis on Dengying Formation high quality reservoirs in Upper Sinian of Sichuan Basin,China[J].Journal of Chengdu University of Technology:Science & Technology Edition,2013,40(6):658-670.
ZENG Fuying,YANG Wei,SUN Ai,et al.Seismic recognition and zonation of the platform margin facies of the Sinian Dengying Formation in central Sichuan Basin[J].Oil & Gas Geology,2017,38(6):1079-1086.