Somali Plate Undocking Kinematics

9706356比勒姆东非正在由于板块构造活动而解体。该项目的目标是测量东非相对于西非横跨非洲裂谷地带的速度。非洲最东端的速度和方向决定了裂谷地带附近火山和地震的生产力，以及裂谷内沉积油藏的形成运动学。圆周率和合作者假设，东非向东北方向滑动，方向与印度和阿拉伯相同。1991年，他们通过对埃塞俄比亚历史地标的测量发现，索马里每1000年向东南部移动不超过1米(非常慢的速度)，但他们无法估计其滑动的东北分量。1997年，该团队将重新测量1991年在埃塞俄比亚安装的非常精确的标记，并测量英国在乌干达进行的一项90年前的调查，这两项调查都对东北运动敏感。这些测量使用全球定位系统(GPS)方法，精度达到3毫米，从而使1997-1991年的速度估计精度达到0.7毫米/年，1997-1907年的速度估计精度(包括不太准确的传统测量方法)大约为2毫米/年。***

9706356 Bilham East Africa is breaking apart as a result of plate tectonic activity. The goal of this project is to measure the velocity of east Africa relative to west Africa across the African Rift zone. The speed and direction of easternmost Africa determines the productivity of volcanoes and earthquakes near the rift zone, and the formative kinematics of sedimentary oil reservoirs within the rift. The PI and collaborators hypothesize that east Africa slips NE in the same direction as India and Arabia. In 1991 they discovered from measurements of historic markers in Ethiopia, that Somalia is not moving to the SE more than 1 m per 1000 years (a very slow rate), but they were unable to estimate its NE component of slip. In 1997 the team will re-measure the very precise markers that were installed in 1991 in Ethiopia, and measure a 90-year-old British survey in Uganda, both of which are sensitive to NE motion. The measurements employ Global Positioning System (GPS) methods accurate to 3 mm, permitting estimation of 1997-1991 velocities to an accuracy of 0.7 mm/year, and 1997-1907 velocities which include less accurate traditional survey methods, to approximately 2 mm/year. ***