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《Bulletin of Mineralogy, Petrology and Geochemistry》
JOPC 2020 Vol.22 Number 3
2020, Vol.22 Num.3
Online: 2020-06-01
REVIEW
LITHOFACIES PALAEOGEOGRAPHY AND SEDIMENTOLOGY
PALAEOGEOGRAPHY AND MINERAL RESOURCES
GEOCHEMISTRY AND SEDIMENTARY ENVIRONMENTS
REVIEW
397
Zhu Xiao-Min, Dong Yan-Lei, Zeng Hong-Liu, Lin Cheng-Yan, Zhang Xian-Guo
Research status and thoughts on the development of seismic sedimentology in China
The seismic sedimentology is a continuous development of seismic stratigraphy and sequence stratigraphy,and has been paid much attention in recent ten years,especially in its principle,continental and marine classic sedimentary sandbodies,carbonate and mixed deposits,prediction of seismic diagenetic facies,fine characterization of sandbodies,new geophysical methods and techniques,RGB fusion of seismic attributes,and 3D visualization carving geobodies,
etc.
The future development of seismic sedimentology should concentrate on seismic geomorphological model,new method of seismic lithology,seismic sedimentology for exploration and exploitation, geophysical inversion methods,and artificial intelligent technology,
etc.
The gradually improvement of theory and methods in seismic sedimentology as well as the extended application of seismic sedimentology in hydrocarbon exploration and exploitation will increase its economic efficiency.
2020 Vol. 22 (3): 397-411 [
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LITHOFACIES PALAEOGEOGRAPHY AND SEDIMENTOLOGY
412
Dong Yan-Lei, Chen Xiang, Wu Wei, Yang Dao-Qing, Yang Ke, Su Bin, Cheng Yi-Fan, Zuo Yi-Wei, Zhao Rui-Xing, Zou Tong, Zhu Xiao-Min
Seismic sedimentology study of the Cretaceous in Chunguang exploration area,northwest of Junggar Basin
Seismic sedimentology is the effective method to depict the spatial and temporal distribution characteristics of sedimentary system. Taking the Chunguang exploration area in the northwest of the Junggar Basin as an example,the sequence boundaries and their distributions were analyzed at first,and the high-resolution sequence framework was thus built. And then the sedimentary types were identified combined with seismic,mud-logging,well-logging,core and analytic data. Under the guidance of seismic sedimentology,the distribution of sedimentary systems were depicted using several techniques including stratal slicing. The results show that: (1)the Cretaceous was divided into four third-order sequences and seven fourth-order sequences in the Chunguang exploration area;(2)four types of sedimentary facies types are identified,including fan delta,braided river delta,hyperpycnal-flow deposits and lake;(3)through the phase adjustment,a good corresponding relationship between seismic amplitude and lithology is established. The frequency decomposition,RGB blending and stratal slicing techniques were carried out,and the spatial-temporal distribution of sedimentary systems in the study area was depicted precisely. During the depositional period of the Hutubi Formation,fan delta was developed in the northwest of the study area,and braided river delta and hyperpycnal-flow deposits were developed in the east,sinuous channels and lateral accretion packages can be observed from the stratal slices. The lake transgression reached the maximum during the depositional period of the Shengjinkou Formation,and it was favorable to development and preservation of hyperpycnal-flow deposits. The inherited fan delta deposits were still developed in the northwest of the study area. Due to the uplift of the northwest area,it could be only developed in the east area with braided deltas and gradually decreased hyperpycnal-flow deposits during the depositional period of the Lianmuqin Formation.
2020 Vol. 22 (3): 412-427 [
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428
Tan Ming-Xuan, Zhu Xiao-Min, Zhang Zi-Li, Liu Qiang-Hu, Shi Wen-Long
Fluvial sequence pattern and its response of geomorphy in depression phase of rift basin: A case study of the Lower Member of Neogene Minghuazhen Formation in Shaleitian Uplift area, Bohai Bay Basin
The sequence classification is a difficulty of sequence stratigraphic study on rivers that are distal to coast area during the depression phase of rift basin. Based on the integrated analysis of logging,cores and seismic data,the case study shows that the Lower Member of Neogene Minghuazhen Formation in the Shaleitian Uplift area in the western Bohai Sea region corresponds to one complete third-order sequence which can be divided into four fourth-order sequences(
i.e.
SQ
m
1-SQ
m
4). Sedimentary hiatus,wide and shallow incised valley and amalgamated channel sand bodies are the main recognition of sequence boundaries in fluvial sequence stratigraphy of the study area. Each fourth-order sequence comprises low and high accommodation systems tracts. According to seismic sedimentological and quantitative geomorphological analysis,low-sinuosity rivers including braided river and low-sinuosity meandering river are well developed in the low accommodation systems tract,whereas the medium- to high-sinuosity meandering rivers are well preserved in the high accommodation systems tract. The change in the new creation of accommodation and the sediment supply exert a significant control on the stacked pattern within different systems tracts.
2020 Vol. 22 (3): 428-439 [
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440
Zhang Zi-Li, Zhu Xiao-Min, Li Qi, Zhang Rui-Feng, Geng Rong-Yan, Cao Lan-Zhu, Shi Rui-Sheng
Differential transgression of rift basin and characteristic response of sedimentary system within sequence framework: An example from the Paleogene Shahejie Formation in Baxian sag, Bohai Bay Basin
Multi-stage differential transgression controls sequence architecture and its sedimentary type and distribution during the tectonic evolution of lacustrine rift basin. Combined with the seismic data of the Baxian sag as well as drilling,logging,core and paleontological materials from 800 exploration wells,the study targeted the Members 1 and 3 of the Shahejie Formation to analyze sequence architecture and sedimentological difference within the sequence framework during the differential lake transgression,based on the investigation of the Paleogene lake basin evolution. The results showed that the fault slope-break slope architecture was well developed with back-stepping deltas and fan deltas during the slow lake transgression of the Member 3 of Shahejie Formation,in which forms thick high quality source rocks. The flexural-gentle slope architecture was well developed with mixed beach bar and small scale nearshore subaqueous fans(fan deltas)during the rapid transgression of the Member 1 of Shahejie Formation. The differential subsidence controlled the sequence architecture,paleogeomorphology and provenance supply,regulating the spatial lithological distribution. And there are significant differences in sequence architecture and sedimentary system during the different evolution stages of the lake basin. On this basis,the response model of sedimentary system characteristics under differential lacustrine transgression is established,which can be used for reference for oil and gas exploration,especially for lithologic oil and gas reservoir in the same type of basin.
2020 Vol. 22 (3): 440-456 [
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457
Qin Yi, Zhu Xiao-Min, Wang Tong, Guo Cheng, Xie Shuang-Hui
Forced regression and its sedimentary response to continental lacustrine rift basin: A case of the Member 3 of Shahejie Formation in Laizhouwan sag,Bohai Bay Basin
Falling stage systems tract(FSST)is an offlap strata with strong relationship with hydrocarbon exploration,which is driven by relative lake-level fall and developed above the highstand systems tract and below the lowstand systems tract of a new sequence. It has no relationship with sediment supply. Based on the theory of sequence stratigraphy and sedimentology,3D seismic data,drilling core data,and well-logging data were comprehensively analyzed. The study showed that the FSST strata was formed in the Member 3 of Shahejie Formation in the Laizhouwan sag. The FSST can be divided into three units,namely as units P1,P2,and P3 from bottom to top. The P1 is the first unit of progradation downlap the bottom of the FSST. The top of the unit P3 is a sequence boundary exhibits subaerial unconformity. The seismic profile along the source direction is characterized by the low-angle oblique progradation reflection that downstream the center of lake basin from west to east. Incised valleys developed on the top of the FSST perpendicular to the source direction. Gamma-ray logging response is manifested by a series of funnel-shaped complex,indicating that the sedimentary response of the FSST was a cycle of coarsening-upward parasequence sets. Comprehensive studies on core interpretation and well-logging analysis showed that the FSST was a fluvial-delta sedimentary system with slumped fan deposits associated with the delta front. Consequently,the FSST is a common result of relative dry climate and falling of lake level,considering regional tectonic evolution,sediment supply,and paleo-climate change. The discovery of the FSST in the Laizhouwan sag has an important geological significance for the sedimentological interpretation,and it offers a guidance for further oil exploration in the study area. In addition,it also serves as a significant reference for future research on the FSST development and exploration in the continental lacustrine rift basin.
2020 Vol. 22 (3): 457-468 [
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469
Li Wei, Zhu Xiao-Min, Duan Hong-Liang, Li He-Yong, Liu Shi-Li
Characteristics and forming mechanism of laminae fine-grained sedimentary rock of the Paleogene Funing Formation in Gaoyou and Jinhu sags,Subei Basin
The deep-water fine-grained deposits can be not only the source rock,but also the reservoir of unconventional oil and gas. Combined with high-precision centimeter-scale core observation,thin section identification,X-ray diffraction whole rock analysis,trace element test and scanning electron microscopy(SEM)analysis,the laminae characteristics and the genesis mechanism of semi-deep to deep lake fine-grained sedimentary rocks in the Member 2 of the Funing Formation are investigated in the Gaoyou and Jinhu sags of the Subei Basin. The results show that the semi-deep and deep lake fine-grained sedimentary rocks of the Member 2 of the Funing Formation in the Gaoyou and Jinhu sags are complex in lithology,and the laminae with different colors are formed by the mixture and superposition of various material components. The horizontal bedding developed in the fine-grained sedimentary rocks can be further divided into thin-laminated and thick-laminated sedimentary structures,whose macroscopic,microscopic characteristics and the composition are different. The complex forming mechanism of laminae includes two aspects: Formation process and preservation process. The generation(or the input)and the precipitation of each component have seasonal significance during the formation of laminae,whereas the preservation of the laminae could be mainly related to the water depth in the study area.
2020 Vol. 22 (3): 469-482 [
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483
Yang Ke, Zhu Xiao-Min, Liu Yu, Liu Xing-Zhou, Guo Feng
Key signatures of turbidite and sandy debris and core examples in Liaohe Basin
Gravity flow is a widely-distributed fluid type in nature. Various classification schemes of gravity flow are proposed by different researchers from different viewpoints. The scheme of turbidity flow and debris flow is adopted in this paper. The sedimentary characteristics of turbidite and sandy debrite are summarized and discussed to clarify most typical facies marks of these two rock types. The study shows that turbidite and sandy debris can be identified by the following typical characteristics during the outcrop and core observation: If the graded bedding is developed in sandstone,it should be identified as turbidite;if the muddy rip-up clast or no bedding structure(massive sandstone)is developed in sandstone,it should be identified as sandy debris. These characteristics are the most reliable signatures to distinguish turbidite and sandy debris. In addition,some other sedimentary structures such as deformation bedding,climbing ripple cross bedding,wavy bedding,parallel bedding,scouring surface,lithologic abrupt interface,and flute cast also have certain indicative significance. It is necessary to make a comprehensive judgment based on the sedimentary background,vertical combination of lithofacies,geophysics and other materials when these characteristics are presented in the study.
2020 Vol. 22 (3): 483-492 [
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493
Li Shun-Li, Li Jing, Chen Bin-Tao, Xu Lei, Yu Xing-He, Hou Guo-Wei, Gao Zhao-Pu
Sedimentary characteristics and controlling factors of large-scale longshore bar in the Oligocene Huagang Formation, Xihu sag
The Xihu sag is located in the eastern depression of the East China Sea Shelf Basin,which is the largest hydrocarbon-bearing sag in this basin. It has been debated on sedimentary environments and sedimentary systems of the Oligocene Huagang Formation as the major reservoir. On the basis of cores,well-logging response,and seismic reflection characteristics,three typical lithofacies types of thick sandstone in the Huagang Formation are identified in the central-eastern Xihu sag,namely as massive gravelly medium sandstone,fine-medium sandstone with swash beddings,and silt-fine sandstone with ripples. Statistics of sedimentary structures parameters indicate the thick-bedded sandstone of the Huagang Formation were developed in washing zone along shoreline with strong hydrodynamic condition and wave action. On the gamma logging curve,the thick sandstone is characterized by low-amplitude,blocky pattern in the lower part,gradually changing to high-amplitude,jagged pattern in the top part. On the seismic profile,mound reflections with flat bottom and convex-up top show the medium amplitude and continuity,indicating the large-scale longshore bar systems. Stacked pattern and spatial distribution were depicted combined with well-logging patterns and matching of seismic attributes and sand content. The longshore bar systems of the Huagang Formation in the Xihu sag were mainly developed at edge of the delta front in the eastern part of the study area,which is formed from the earlier braided-river delta front reworked by wave action during base level fall.
2020 Vol. 22 (3): 493-503 [
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504
Liu Zi-Liang, Deng Kun, Shi Ze-Jin, Tian Ya-Ming, Wang Yong, Shen Fang, Tan Qian, Gong Xiao-Xing
Sedimentary facies and model of shallow water carbonates platform of the Lower Cambrian Longwangmiao Formation in Sichuan Basin
Building the sedimentary model accurately and delineating the spatial-temporal distribution of grain bank are the keys to increase the rate of success in natural gas exploration. Thus,the types and characteristics of sedimentary facies of the Longwangmiao Formation in the Sichuan Basin were studied based on field outcrops,drilling,logging and seismic data. Taking a fourth-order sequence systems tract as a unit,the spatial-temporal distribution characteristics of sedimentary facies within the chronostratigraphic framework were precisely described,and the depositional model of the Longwangmiao Formation was established to reveal the development mechanisms of grain bank and point out the future natural gas exploration. The results showed that: (1)The typical shallow carbonate platform depositional system was developed in the Longwangmiao Formation of the Sichuan Basin and its surrounding areas. Mixed tidal flat,restricted platform(microfacies types including grain bank,dolomitic tidal flat,lagoon,and gypsum lagoon),open platform(microfacies types including grain bank,lime tidal flat),platform margin,and slope-basin were developed from the edge to the interior of the basin;(2)A sedimentary model was established,which was characterized by “one depression,two uplifts,and two grain banks in the form of belts”. The development of grain banks was mainly controlled by palaeo-topography and relative sea-level fluctuation. It was mainly developed in the highstand systems tract of a fourth-order sequence vertically,and distributed as a belt along the platform margin and around the lagoon area horizontally. Our paper pointed out the grain shoal deposits are the material basis for the development of high-quality reservoirs,the results thus provide a sedimentary geological basis for future natural gas exploration of the Cambrian Longwangmiao Formation in the Sichuan Basin.
2020 Vol. 22 (3): 504-522 [
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523
Lei Tao, Deng Hu-Cheng, Wu Dong, Fu Mei-Yan, Tang Ming-Yuan, Cui Lu, Ding Xiao-Qi, Xia Yu, Xie Xin-Hui
Depositional model of the lower-middle Ordovician Majiagou Formation in Daniudi Gas Field,Ordos Basin
Carbonate rocks are the important Paleozoic oil and gas reservoirs in the Ordos Basin. Based on the comprehensive analyses of core and thin section and logging data,the depositional subfacies,including evaporation platform,open platform and confined platform,were identified in the lower-middle Ordovician Majiagou Formation of the Daniudi Gas Field in the Ordos Basin. The characteristics of different depositional subfacies were analyzed in detail,and the depositional model of the lower-middle Majiagou Formation in the Daniudi Gas Field controlled by sea level fluctuation was established. The sea level was relatively low during the depositional period of the Members 1-3 of the Majiagou Formation,resulting in the development of evaporation platform. The saline lake of the Members 1 and 3 of the Majiagou Formation was mainly distributed in the southeast with the gypseous lake around it. The sea level rose slightly during the depositional period of the Member 2 of the Majiagou Formation,and subsequently muddy-dolomitic flat and gypseous-dolomitic flat developed in the entire study area from bottom to top. The open platform was developed in the Member 4 of the Majiagou Formation when the sea level reached the maximum,and uniformly distributed lime flat and overlying dolomitic-lime flat covered the whole area in the platform. The confined platform predominated the Member 5 of the Majiagou Formation during the regression-transgression-regression. In the Member 5 of the Majiagou Formation,the dolomitic flat of the 7th-10th sub-members covered the whole area,the large extent of muddy-dolomitic flat expanded from northwest to southeast in the 6th sub-member,and the lime flat of the 5th sub-member was developed in the central part with the scattered dolomitic flat around it.
2020 Vol. 22 (3): 523-538 [
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PALAEOGEOGRAPHY AND MINERAL RESOURCES
539
Shen Mo, Zhu Xiao-Min, Li Cheng-Shan, Zhang Wen-Xuan, Cheng Yi-Fan, Jiang Meng-Ya
Diagenesis of the Chang 9 oil-bearing interval of Triassic Yanchang Formation in Zhengning area,Ordos Basin
Based on the description of the core,casting thin sections,scanning electron microscopy and other data,the rock types,diagenesis types,distribution characteristics and main controlling factors of diagenetic facies were systematically studied for the Member 9 oil-bearing interval of Triassic Yanchang Formation in the Zhengning area of the Ordos Basin. The rock types of the Member 9 oil-bearing interval are mainly composed of fine-to medium-grained lithic arkose and feldspathic lithic sandstone. The diagenesis types mainly include compaction,chlorite cementation,calcite cementation,ankerite cementation,siliceous cementation,calcite replacement and dissolution. The Member 9 oil-bearing interval in the study area is currently in the middle diagenesis stage A. According to the stratification frequency and plastic mineral content,the rock type can be divided into high-frequency stratification flake-like plastic-mineral rich silt-to fine-grained sandstone rock facies and low-frequency stratification rigid-mineral rich fine-medium-grained sandstone rock facies. The former distributed at the edge of underwater distributary channel with the densely compacted diagenetic facies are developed,while the latter formed in the main channel of underwater distributary channel and mouth bar. The thick single sand-body and the thick multi-storey sand-body can be divided according to the sand-body structure. The thick single sand body is a single channel or mouth bar sand-body,which is characterized by calcite-filling cementation phase in the upper part and chlorite-lining cementation phase in the lower part. The thick multi-storey sand-body is formed by multi-stage channel sand-body scour and superposition,which develops calcite-chlorite-filling cementation phase. The ductile grain content is the most important factor influencing compaction strength,resulting in a poor reservoir quality superposed carbonate cementation and the inhibition of the compaction by the early chlorite-lining cementation is an critical condition for the favorable reservoir development. The comprehensive evaluation shows that the favorable reservoir of Member 9 oil-bearing interval of Yanchang Formation developed with the chlorite-lining cementation facies. The next is the chlorite-calcite-cementation filling phase. The reservoirs with the lowest quality are developed at the calcite-filling cementation phase and compacted dense phase.
2020 Vol. 22 (3): 539-554 [
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555
Zhu Shi-Fa, Jia Ye, Wan Chao-Fan, Ma Li-Chi, Cui Dian, Sun Chao, Jing An-Yu
Diagenetic of the Mesozoic complex weathering crust reservoir rock in Fulin subsag,Jiyang Depression
The formation of weathering crust reservoirs and the analysis of their differences have become the current research focus of reservoir geology. The Mesozoic oil and gas exploration in the Fulin subsag of Zhanhua sag in the Jiyang Depression of Bohai Bay Basin has encountered its bottleneck. Only the weathering crust at top of the Cretaceous is currently penetrated by exploration wells and the weathering crust reservoir is characterized by complex lithology and high heterogeneity. In order to enhance exploration in the Mesozoic buried hill reservoir in the study area and even the Jiyang Depression,it's of great importance to figure out diagenetic evolution,reservoir space types and their combination relationships. The complex lithology of weathering crust reservoir rock of the Cretaceous Xiwa Formation in the Fulin subsag was studied by core and thin section observation combining with well logging data. The results show that the key lithologies of weathering crust include andesite and tuff,followed by dyke,cryptoexplosive breccia and glutenite. During the complex burial process,different tectonic units underwent the evolution of 'sag-uplift-uplift' or 'sag-uplift-sag',resulting in significant differences for diagenetic sequence and pore evolution of different reservoir rocks. The primary pore types and their genesis of igneous and clastic rocks are obviously different,but the present reservoir space is dominated by secondary pores,especially dissolution pores. The dissolved material includes porphyry,matrix and volcanic debris. The dominant fluid for dissolution is variable. In addition to the atmospheric fresh water rich in CO
2
during the uplifting and exposure,the organic acid discharged during the maturation of organic matter has a positive effect on improving reservoir quality. The formation of favorable weathering crust reservoir rock is controlled by lithology,burial evolution and diagenetic fluid. On the whole,the reservoir quality order of the Cretaceous Xiwa Formation in the Fulin subsag is as follow: Volcaniclastic rock,vesicular andesite,tuff,subvolcanic rock. Different weathering crust reservoir rocks in the study area underwent different diagenetic modification during the complex burial process.
2020 Vol. 22 (3): 555-569 [
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GEOCHEMISTRY AND SEDIMENTARY ENVIRONMENTS
570
Zhang Qin, Wang Bo-Han, Zhou Chen, Sun Zu-Yu, Mei Xiao-Han, Yuan Cheng-Shuai, Wang Kai
Characteristics and genesis of iron formation in the Changlongshan Formation of Qingbaikou System in the Ming Tombs area,Beijing
Iron formation is widely distributed through the entire Precambrian geological record,however,there is no report on the outcropped Precambrian iron formation in the Changlongshan Formation of the Qingbaikou System in North China. Based on field investigation,XRD,SEM,ICP-MS and other methods,the distribution and mineral composition of iron formation and the source of ore-forming materials outcropped in the Ming Tombs area were studied in this paper to investigate the genesis of iron formation. The study showed that the main component of iron formation was hematite,which was associated with quartz,glauconite and other minerals. The iron formation of the Changlongshan Formation was divided into two types. Type I is associated with glauconite with relatively smaller thickness,and it is characterized by bands of glauconite sandstone interbeded with iron sandstone and near-spherical hematite microscopically. Type II is not accompanied by glauconite with relatively larger thickness,and it is represented by black iron-rich layers intercalated with quartz lens and acicular or snowflake hematite under the microscope. Tectonic evolution and trace element analysis showed that the iron source was mainly derived from the irony weathering crust at the top of the Xiamaling Formation. The type I iron formation is a mixture of chemical colloid and glauconite weathering,and the type II iron formation is mainly formed by colloidal chemical deposition and could undergo mylonitization in the later stage. The research results provide a sedimentary geological basis for distribution and prospecting of the Precambrian iron formation in North China,and it is also of great significance for enriching the metallogenic mechanism of the iron formation and revealing the tectonic evolution of Proterozoic of North China.
2020 Vol. 22 (3): 570-586 [
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587
Ye Lei, Zhu Xiao-Min, Zhang Rui-Feng, Xie Shuang-Hui, Gao Yuan, Tang Hong, Qi Xue-Zhu, Chen Ya-Qing
Sedimentary environment of shallow-water delta and beach-bar of the Member 1 of Shahejie Formation in Lixian slope of Raoyang sag,Jizhong Depression
Shallow-water delta and beach-bar are not only the current research hotspots of sedimentology,but also the important sedimentary types of sand body for oil and gas exploration. The sedimentary environment controls the development and evolution of shallow-water delta and beach-bar. Based on the analysis of core,well,logging,spore-pollen fossils and trace elements,the types of sedimentary system and sedimentary environment of the Member 1 of Paleogene Shahejie Formation in the Lixian slope of the Raoyang sag,Jizhong Depression was studied integratedly. The results showed that: (1)Shallow-water delta and beach-bar deposits were mainly developed in the study area in the Member 1 of Shahejie Formation(E
s
1
). The inner and outer shallow-water delta fronts predominated during the deposition of the bottom sandstone section of the lower sub-Member of E
s
1
. Lake level rose and shallow-water delta retrograded,and beach-bar predominated during the deposition of the special lithologic section of the lower sub-Member of E
s
1
. The lake level fell,and the delta that prograded to the center of lake. The main sedimentary body changed into the shallow-water delta during the deposition of the upper sub-Member of E
s
1
. (2)The sedimentary evolution of shallow-water delta and beach-bar are controlled by sedimentary environment. During the deposition of the bottom sandstone section of the lower sub-Member of E
s
1
,the study area was in a relatively arid subtropical climate,and the lake was in the relatively shallow oxidized and brackish setting,which was conducive for the development of the shallow-water delta. During the deposition of the special lithologic section of the lower sub-Member of E
s
1
,large-scale lake transgression increased the lake level,while the provenance supply was limited in the study area. The lake changed into the reducing setting within the relatively humid climate and increased salinity,which was favorable for the formation of beach-bar. During the deposition of the upper sub-Member of E
s
1
,the source supply was sufficient,and the study area was in the relatively humid subtropical climate. Meanwhile,the lake basin shrank,the lake level decreased. The relatively low salinity and oxidized fresh water setting was conductive for the deposition of the shallow-water delta.
2020 Vol. 22 (3): 587-600 [
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