Sedimentary Reflection of Tectonic Activities of Fault Depression Basin-taking Lufeng Depression as an Example

Zhen Zhang, Jianhua Guo, Wang Yu
2017 Modelling Measurement and Control C  
Lufeng depression is a fault depression basin with abundant petroleum resources. It's of significance to analyze the structure and sedimentary situation of the study area. 11 third-order seismic sequence boundaries are identified in Wenchang Formation of fault-depression period and Enping Formation of fault-sag period and 10 third-order sequences of type-I are divided based on the seismic data. According to the features of seismic facies and log facies, the sedimentary facies of fault
more » ... period include fan delta, sublacustrine fan, lacustrine facies, delta facies, etc. Delta facies and lacustrine facies were found in the fault sag period. Wenchang Formation deposited during fault depression period and Enping Formation deposited during fault sag period both can be subdivided into initial fault depression period, rapid fault depression period, intensive fault depression period and fault depression shrinking period. However, there is obvious difference between the sedimentary characteristics of Wenchang Formation and Enping Formation. Ancient landform of Wenchang Formation at the depositional stage features large terrain elevation difference, deep water bodies and rich types of sedimentary facies, while the landform of Enping Formation features flat terrain, shallow waters, and rather simple sedimentary facies types. The change rules of fan bodies in fault depression period and in fault sag period are consistent. The fan bodies all advance towards the basin, except the one in the intensive fault depression period, which flinches towards the provenance.
doi:10.18280/mmc_c.780206 fatcat:igw3iiqvp5euvkysajpivyqtzi