Xiaohui Li, Yuliang Su, Guanglei Ren, Feixiang Gao, Shuhong Yan, Huachao Sun, Hui Ran, Mengdi Cui
{"title":"具有季节性水动力变化的沙质辫状河沉积结构:中国鄂尔多斯盆地二叠系下统石河子地层的启示","authors":"Xiaohui Li, Yuliang Su, Guanglei Ren, Feixiang Gao, Shuhong Yan, Huachao Sun, Hui Ran, Mengdi Cui","doi":"10.1007/s11707-024-1110-5","DOIUrl":null,"url":null,"abstract":"<p>A sandy, braided river is a typical type of river that exists in ancient and modern alluvial plains and is inherent with significant seasonal water discharge variations. The variations play an important role in the depositional process and the formation of the sedimentary architecture of braided rivers. In this paper, a braided river outcrop along the Yellow River in Fugu is used to describe the effects of seasonal hydrodynamic variations on braided river sedimentary architecture. The results show that the braided channel network exhibits two different patterns during flood period and normal period. During flood periods, the main braided channels surrounding channel bars and the secondary braided channels distributed on the top of the channel bars coexist, forming a highly braided channel network. Migration of the main braided channels control the formation of middle channel bars and side bars. The generation and evolution of the secondary braided channels reformed the upper part of preexisting channel bars and produced affiliated bars along their flow path. During the normal period, water levels decrease, causing the secondary river channels to be abandoned and forming abandoned channels, and only the main braided channels stay active. In the long term sedimentation process, strong water flow during the flood period continuously erodes pre-existing sediments and forms new sediments, while weak water flow during the normal period can only reform the main braided channels and their adjacent channel bar sediments. Based on differences in sedimentary processes and associated hydrodynamic conditions, braided river sediments are divided into two combinations. The strong hydrodynamic combination includes main braided channels, middle channel bar, and side bar, while the weak hydrodynamic combination includes secondary braided channels, abandoned channels, and affiliated bars. The proportion of strong hydrodynamic combinations is much larger than that of weak hydrodynamic combinations. Based on this, we construct a braided river sedimentary architecture model that is helpful for the fine characterization of subsurface oil and gas reservoirs.</p>","PeriodicalId":48927,"journal":{"name":"Frontiers of Earth Science","volume":"1 1","pages":""},"PeriodicalIF":1.8000,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Sedimentary architecture of a sandy braided river with seasonal hydrodynamic variations: insights from the Permian Lower Shihezi Formation, Ordos Basin, China\",\"authors\":\"Xiaohui Li, Yuliang Su, Guanglei Ren, Feixiang Gao, Shuhong Yan, Huachao Sun, Hui Ran, Mengdi Cui\",\"doi\":\"10.1007/s11707-024-1110-5\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>A sandy, braided river is a typical type of river that exists in ancient and modern alluvial plains and is inherent with significant seasonal water discharge variations. The variations play an important role in the depositional process and the formation of the sedimentary architecture of braided rivers. In this paper, a braided river outcrop along the Yellow River in Fugu is used to describe the effects of seasonal hydrodynamic variations on braided river sedimentary architecture. The results show that the braided channel network exhibits two different patterns during flood period and normal period. During flood periods, the main braided channels surrounding channel bars and the secondary braided channels distributed on the top of the channel bars coexist, forming a highly braided channel network. Migration of the main braided channels control the formation of middle channel bars and side bars. The generation and evolution of the secondary braided channels reformed the upper part of preexisting channel bars and produced affiliated bars along their flow path. During the normal period, water levels decrease, causing the secondary river channels to be abandoned and forming abandoned channels, and only the main braided channels stay active. In the long term sedimentation process, strong water flow during the flood period continuously erodes pre-existing sediments and forms new sediments, while weak water flow during the normal period can only reform the main braided channels and their adjacent channel bar sediments. Based on differences in sedimentary processes and associated hydrodynamic conditions, braided river sediments are divided into two combinations. The strong hydrodynamic combination includes main braided channels, middle channel bar, and side bar, while the weak hydrodynamic combination includes secondary braided channels, abandoned channels, and affiliated bars. The proportion of strong hydrodynamic combinations is much larger than that of weak hydrodynamic combinations. Based on this, we construct a braided river sedimentary architecture model that is helpful for the fine characterization of subsurface oil and gas reservoirs.</p>\",\"PeriodicalId\":48927,\"journal\":{\"name\":\"Frontiers of Earth Science\",\"volume\":\"1 1\",\"pages\":\"\"},\"PeriodicalIF\":1.8000,\"publicationDate\":\"2024-08-22\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Frontiers of Earth Science\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://doi.org/10.1007/s11707-024-1110-5\",\"RegionNum\":4,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"GEOSCIENCES, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Frontiers of Earth Science","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1007/s11707-024-1110-5","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
Sedimentary architecture of a sandy braided river with seasonal hydrodynamic variations: insights from the Permian Lower Shihezi Formation, Ordos Basin, China
A sandy, braided river is a typical type of river that exists in ancient and modern alluvial plains and is inherent with significant seasonal water discharge variations. The variations play an important role in the depositional process and the formation of the sedimentary architecture of braided rivers. In this paper, a braided river outcrop along the Yellow River in Fugu is used to describe the effects of seasonal hydrodynamic variations on braided river sedimentary architecture. The results show that the braided channel network exhibits two different patterns during flood period and normal period. During flood periods, the main braided channels surrounding channel bars and the secondary braided channels distributed on the top of the channel bars coexist, forming a highly braided channel network. Migration of the main braided channels control the formation of middle channel bars and side bars. The generation and evolution of the secondary braided channels reformed the upper part of preexisting channel bars and produced affiliated bars along their flow path. During the normal period, water levels decrease, causing the secondary river channels to be abandoned and forming abandoned channels, and only the main braided channels stay active. In the long term sedimentation process, strong water flow during the flood period continuously erodes pre-existing sediments and forms new sediments, while weak water flow during the normal period can only reform the main braided channels and their adjacent channel bar sediments. Based on differences in sedimentary processes and associated hydrodynamic conditions, braided river sediments are divided into two combinations. The strong hydrodynamic combination includes main braided channels, middle channel bar, and side bar, while the weak hydrodynamic combination includes secondary braided channels, abandoned channels, and affiliated bars. The proportion of strong hydrodynamic combinations is much larger than that of weak hydrodynamic combinations. Based on this, we construct a braided river sedimentary architecture model that is helpful for the fine characterization of subsurface oil and gas reservoirs.
期刊介绍:
Frontiers of Earth Science publishes original, peer-reviewed, theoretical and experimental frontier research papers as well as significant review articles of more general interest to earth scientists. The journal features articles dealing with observations, patterns, processes, and modeling of both innerspheres (including deep crust, mantle, and core) and outerspheres (including atmosphere, hydrosphere, and biosphere) of the earth. Its aim is to promote communication and share knowledge among the international earth science communities