东非裂谷Turkana坳陷新生代构造演化及动力学

作为威尔逊旋回萌芽阶段的典型陆内裂谷，东非裂谷是研究板块构造运动学和动力学的天然场所。新生代东非裂谷东支Turkana坳陷受前寒武系基底先存构造及中生代裂谷活动的影响，分析其演化及动力学机制，对进一步深入认识大陆裂谷演化过程具有重要的意义。基于低温热年代学、钻井及野外露头资料，结合地震资料解释和断层活动性分析，重新厘定了Turkana坳陷新生代裂谷演化时序，将新生代裂谷演化过程分为4个阶段，裂谷演化具有"南早北晚，先宽后窄，向东迁移"的特点。通过探讨裂谷发育的成因模式，认为新生代裂谷演化整体上受控于先存构造和地幔柱的联合作用，地幔活动迁移影响着火山及裂谷活动的迁移，并导致了裂谷发育模式和动力学机制的变化。 

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

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.