Assessment of lake-level variations to decipher geological controlling factors and depositional architecture of Lake Fuxian, Yunnan Plateau: preliminary insights from geophysical data

• Published in: Geomechanics and geophysics for geo-energy and geo-resources. Vol. 10; no. 1; pp. 1 - 26
• Main Authors: Ashraf, Umar, Zhang, Hucai, Anees, Aqsa, Zhang, Xiaonan, Duan, Lizeng
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.12.2024; Springer Nature B.V; Springer
• Subjects: Energy; Engineering; Environmental Science and Engineering; Foundations; Freshwater; Freshwater lakes; Geoengineering; Geological controlling factors; Geological structures; Geology; Geophysical data; Geophysical measurements; Geophysics/Geodesy; Geotechnical Engineering & Applied Earth Sciences; Graben; Hydraulics; Inland water environment; Lake basins; Lake deposits; Lake Fuxian; Lake sediments; Lake-level variations; Plateaus; Sedimentary facies; Sedimentary thickness; Sediments; Seismic reflection profiles; Seismic response; Seismic surveys; Sequences; Sequencing; Stratigraphy; Tectonics; Thickness; Sedimentary thickness; Lake Fuxian; Lake-level variations; Geophysical measurements; Geological controlling factors
• ISSN: 2363-8419; 2363-8427
• DOI: 10.1007/s40948-024-00777-7

Lake Fuxian is one of the deepest tectonic plateau freshwater lakes in the southeastern Tibetan Plateau, China. However, questions such as how old the lake is, how deep the total sedimentary thickness sequences are, and what landscape of the lake basin settings and geological structures are unknown. Here, based on fifteen seismic reflection profiles, we applied seismic facies and seismic sequence stratigraphic analyses to interpret the lake sequences. The results of the seismic response reveal that the maximum thickness of the sedimentation is ca. 1238 m and lies toward the NNE region of the lake basin on the L10-2 survey line. Lake sediments can be categorized into five seismic sequences and six seismic horizons. The oldest clinoforms in the deepest sequence (Sq-5) show that the depositional center was shifted to ~ 19 km from the NNE region to the SSW modern location and was ~ 930 m lower than the current lake floor. Multiple and complex tectonic activities strongly impacted on the lake basin, and a series of normal faults created an overall crustal extensional regime, resulting in the formation of many horst and graben structures. Article highlights Five sequences and fourteen seismic facies are categorized in lake basin. Coastline migrated ~19 km to SSW in northern basin of its current location. Maximum thickness towards south is 303m on L3 and 1238m on north at L10-2. Tectonic activity played important role in forming horst-graben structures. Major controlling factors are tectonics, subsidence & sedimentary thickness.