Sedimentary system reconstruction and implications for hydrocarbon exploration of the Cretaceous Napo Formation Main-M1 submember in Oriente Basin,South America
LI Fayou1, BAN Shuyue2,3, WANG Guangfu1, SUN Jianfang1, DING Feng1, SUN Yu1, WANG Tengyu2,3, XU Hai1, CHEN Shiwang1, XIA Changsheng2,3, ZHENG Naixi2,3, BAO Zhidong2,3
1 Petroleum Exploration and Production Research Institute,Sinopec,Beijing 102206,China;
2 College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China;
3 National Key Laboratory of Petroleum Resources and Engineering,China University of Petroleum(Beijing),Beijing 102249,China
The Oriente Basin of Ecuador is one of the most important hydrocarbon-bearing basins in the Andean Foreland Basin Group of South America. The Main-M1 submember of the Upper Cretaceous Napo Formation,as one of the main exploration and developement formations,has been controversial in terms of its depositional environment,and its depositional system and evolutionary process remain unclear. Based on core,well logs and borehole cuttings,the main sedimentary microfacies types,depositional systems and evolutionary processes of Main-M1 submember were investigated in this study. The results show that the study area is located in a marine-continental transition environment with complex hydrodynamic conditions,and a tidal delta develops in the east,which gradually transitions into a shallow shelf environment in the west. In the study area,eight types of sedimentary microfaces including subaqueous distributary channel,subaqueous inter-channel,tidal channel,tidal sand bar,tidal flat,and tidal inter-channel,are recognized. According to the petrographic characteristics,the Main-M1 submember is further divided into three sub-layers. By analyzing the lithological assemblages of the three submembers,it is determined that during depositional of the Main-M1 submember,the Auca paleoarchelon gradually formed,and meanwhile the relative sea level of the study area rose due to the flexural effect. The three submembers overall show a gradual deepening upward trend and the tidal delta continuously retreated landward. Based on the reconstruction of the tidal delta-shelf depositional system during deposition of the Main-M1 submember,the subaqueous distributary channel and the leading sand bar in the eastern part of the study area are considered to have certain exploration potential for lithologic reservoirs.
LI Fayou,BAN Shuyue,WANG Guangfu et al. Sedimentary system reconstruction and implications for hydrocarbon exploration of the Cretaceous Napo Formation Main-M1 submember in Oriente Basin,South America[J]. JOPC, 2024, 26(1): 17-27.
[1] 陈杰,陈果,周绪峰,李波,林波,陈琴,蒲彬. 2021. 厄瓜多尔奥连特叠合盆地白垩系油气成藏特征与主控因素分析. 四川地质学报, 41(4): 613-621.
[Chen J,Chen G,Zhou X F,Li B,Lin B,Chen Q,Pu B.2021. Controlling factors of the Cretaceous hydrocarbon accumulation in the Oriente Superimposed Basin,Ecuador. Acta Geologica Sichuan, 41(4): 613-621]
[2] 陈杰,童明胜,陈果. 2022. 奥连特盆地北部灰岩增厚成因及储层预测分析. 西南石油大学学报(自然科学版), 44(6): 43-53.
[Chen J,Tong M S,Chen G.2022. The reason of limestone formation thickering and its effect to reservoir in the North of Oriente Basin. Journal of Southwest Petroleum University(Science & Technology Edition), 44(6): 43-53]
[3] 陈诗望,姜在兴,高彦楼,胡学质,秦兰芝,徐小林. 2008a. 厄瓜多尔Oriente盆地南部区块沉积相模式及有利目标区预测. 油气地质与采收率, 15(2): 20-23,Ⅱ.
[Chen S W,Jiang Z X,Gao Y L,Hu X Z,Qin L Z,Xu X L.2008a. Sedimentary facies model and favorable target areas prediction,south block,Oriente Basin,Ecuador. Petroleum Geology and Oil Recovery, 15(2): 20-23,Ⅱ]
[4] 陈诗望,姜在兴,田继军,秦兰芝,徐小林. 2008b. 厄瓜多尔Oriente盆地南部区块沉积特征. 海洋石油, 28(1): 31-35.
[Chen S W,Jiang Z X,Tian J J,Qin L Z,Xu X L.2008b. Sedimentary characteristics in the South Block of Oriente Basin,Ecuador. Offshore Oil, 28(1): 31-35]
[5] 马中振,谢寅符,陈和平,张志伟,周玉冰,王丹丹,刘亚明,阳孝法. 2014. 南美典型前陆盆地斜坡带油气成藏特征与勘探方向选择: 以厄瓜多尔Oriente盆地M区块为例. 天然气地球科学, 25(3): 379-387.
[Ma Z Z,Xie Y F,Chen H P,Zhang Z W,Zhou Y B,Wang D D,Liu Y M,Yang X F.2014. Hydrocarbon accumulation feature and exploration direction selection: taking M Block of Oriente Basin,Ecuador as an example. Natural Gas Geoscience, 25(3): 379-387]
[6] 彭旸,龚承林,李顺利. 2022. 河流—波浪—潮汐混合作用过程研究进展. 沉积学报, 40(4): 957-978.
[Peng Y,Gong C L,Li S L.2022. Recent advances in river-wave-tide mixed process. Acta Sedimentologica Sinica, 40(4): 957-978]
[7] 彭旸,Ronald J.Steel,龚承林,魏小洁,盛莉娜. 2023. 潮汐沉积过程及沉积特征研究综述. 古地理学报, 25(5): 1069-1089.
[Peng Y,Ronald J.Steel,Gong C L,Wei X J,Sheng L N.2023. A review on tidal depositional processes and characteristics. Journal of Palaeogeography(Chinese Edition), 25(5): 1069-1089]
[8] 谢寅符,马中振,刘亚明,刘剑波,阳孝法,孙作兴. 2014. 南美洲常规油气资源评价及勘探方向. 地学前缘, 21(3): 101-111.
[Xie Y F,Ma Z Z,Liu Y M,Liu J B,Yang X F,Sun Z X.2014. South America conventional oil and gas resource assessment and exploration direction. Earth Science Frontiers, 21(3): 101-111]
[9] 张健. 2023. 南美奥连特盆地勘探开发一体化实践: 以A项目J油田为例. 石化技术, 30(1): 170-172.
[Zhang J.2023. Integrated exploration and development practice in South America Oriente Basin: a case study of J Oilfield of Project A. Petrochemical Industry Technology, 30(1): 170-172]
[10] 张天宇. 2019. Oriente盆地A油田M1层潮控河口湾沉积微相研究及储层描述. 中国石油大学(华东)硕士学位论文: 69-73.
[Zhang T Y.2019. Sedimentary microfacies and reservoir description in tidaldominated estuary of M1 Formation of A oilfield,Oriente Basin. Masteral dissertation of China University of Petroleum(East China): 69-73]
[11] Baby P,Rivadeneira M,Barragán R,Christophoul F.2013. Thick-skinned tectonics in the Oriente foreland basin of Ecuador. Geological Society,London,Special Publications, 377: 59-76.
[12] Bajolet F,Chardon D,Rouby D,Dall’Asta M,Loparev A,Couëffe R,Roig J Y.2022. The sediment routing systems of Northern South America since 250 ma. Earth-Science Reviews, 232: 104139.
[13] Boschman L M.2021. Andean mountain building since the Late Cretaceous: a paleoelevation reconstruction. Earth-Science Reviews, 220: 103640.
[14] Chen Y W,Wu J,Suppe J.2019. Southward propagation of Nazca subduction along the Andes. Nature, 565: 441-447.
[15] Gutiérrez E G,Horton B K,Vallejo C,Jackson L J,George S W M.2019. Provenance and geochronological insights into Late Cretaceous-Cenozoic foreland basin development in the Subandean Zone and Oriente Basin of Ecuador. Andean Tectonics. Amsterdam:Elsevier, 237-268.
[16] Haq B U.2014. Cretaceous eustasy revisited. Global and Planetary Change, 113: 44-58.
[17] Higgs R.2002. Tide-dominated estuarine facies in the Hollin and Napo(“T”and “U”)formations(Cretaceous),Sacha field,Oriente Basin,Ecuador Discussion. AAPG Bulletin, 86(2): 329-334.
[18] Lee G H,Eissa M A,Decker C L,Castagna J P,O'Meara D J,Marín H D.2006. Aspects of the petroleum geology of the Bermejo field,northwestern oriente basin,Ecuador. Journal Petroleum Geology, 27: 335-356.
[19] Martin-Gombojav N,Winkler W.2008. Recycling of Proterozoic crust in the Andean Amazon foreland of Ecuador: implications for orogenic development of the Northern Andes. Terra Nova,20(1): 22-31.
[20] Mathalone J M P,Manuel M R.1995. Petroleum geology of the sub-andean basins of Peru. Petroleum Basins of South America. American Association of Petroleum Geologists.
[21] Michaud F,Witt C,Royer J.2009. Influence of the subduction of the Carnegie volcanic ridge on Ecuadorian geology: reality and fiction. Geological Society of America Memoirs,204(0): 217-228.
[22] Shanmugam G,Poffenberger M,Álava J T.2000. Tide-Dominated Estuarine Facies in the Hollin and Napo(“T”and “U”)Formations(Cretaceous),Sacha Field,Oriente Basin,Ecuador. AAPG Bulletin, 84(5): 652-682.
[23] Vallejo C,Romero C,Horton B K,Spikings R A,Gaibor J,Winkler W,Esteban J J,Thomsen T B,Mariño E.2021. Jurassic to Early Paleogene sedimentation in the Amazon region of Ecuador: implications for the paleogeographic evolution of northwestern South America. Global and Planetary Change, 204: 103555.
[24] Vallejo C,Spikings R A,Horton B K,Luzieux L,Romero C,Winkler W,Thomsen T B.2019. Late Cretaceous to Miocene stratigraphy and provenance of the coastal forearc and Western Cordillera of Ecuador: evidence for accretion of a single oceanic plateau fragment. Andean Tectonics. Amsterdam: Elsevier, 209-236.
[25] Vallejo C,Tapia D,Gaibor J,Steel R,Cardenas M,Winkler W,Valdez A,Esteban J,Figuera M,Leal J,Cuenca D.2017. Geology of the Campanian M1 sandstone oil reservoir of eastern Ecuador: a delta system sourced from the Amazon Craton. Marine and Petroleum Geology, 86: 1207-1223.