Cenozoic tectonic evolution and dynamics of Turkana Depression, East African Rift

Abstract

As a typical continental rift at the embryonic stage of the Wilson cycle, the East African Rift System (EARS) is a natural place for studying plate tectonic kinematics and dynamics. The Turkana area of the EARS is of special interest science, which has been influenced by pre-existing fabrics and Mesozoic rift activities. The evolution of EARS has important significance for understanding and perfecting the evolution process of continental rifts. Based on the collected low-temperature thermochronometer study results, drilling and field outcrop data, combined with seismic data, through comprehensive analysis of rift activity time and fault activity rate analysis, this study redefined the rift evolution sequence in Turkana area, and the Cenozoic rift activity in the study area can be divided into four stages of evolution. The characteristics of the evolution of the study area are summarized as follows: early stage rift began in the south and later stage in the north, first wide rift and later narrow rift, moving to the eastward. The rift evolution is generally controlled by the combined action of pre-existing fabrics and mantle plume activity. The migration of mantle activities not only affects the migration of volcanoes and rift activities, but also may change the development pattern.

Keywords

• east african rift system (ears)
• turkana depression
• fault activity rate
• rift evolution
• plate tectonic