本文利用FMTOMO层析成像软件以及远震P波走时数据,获得青藏高原东缘地区300km深度范围内的P波速度结构,得到以下结果:①在60~140km深度范围内,102°E~104°E、29°N~31°N,四川盆地西南部存在一个相对低速区域;②在60~140km深度范围内,沿着龙门山断裂带,在龙门山断裂带的西北侧区域出现相对高速的现象;③在190~290km深度范围内,青藏高原东缘西南区域存在着高速现象,龙门山断裂带、安宁河断裂带不再是高低速区域的分界带。
The P-wave velocity structure in the eastern edge of Tibetan plateau within the depth range of 300km was obtained by using the FMTOMO seismic tomography software and teleseismic teaveltimes data.Our results show that:(1)From 60 km to 140 km,102°E~104°E,29°N~31°N,there is a relative low velocity region in the southwest of Sichuan basin.(2)In the depth range from 60km to 140 km,the phenomenon of relative high velocity appears along the northwest side of Longmenshan fault.(3)In the depth range from 190 km to 290 km,there is a high velocity phenomenon in the southwest region of eastern edge of Tibetan plateau.The Longmenshan fault and Anninghe fault are not the boundary between high velocity region and low velocity region.