尼日利亚南部大陆边缘重力场特征及解释

摘要

Variable characteristics of the free air gravity anomaly and Bouguer gravity anomaly were analyzed by using the ship gravity data obtained from international cooperative survey between China and Nigeria . Through analyzing two gravity profiles that start from continental shelf ,slope and extend to the deep sea basin ,we can get the density structure of the crust .The results of research imply that the crustal thickness has been cascade thinning from continental shelf ,slope to deep sea plain .The thinned range on the east side is greater than that on the west side ,it decreases from 24 km to 10 km on the east side and 21 km to 14 km on the west side .%利用中国-尼日利亚国际合作航次获得的船载重力数据,分析了尼日利亚南部大陆边缘的自由空间重力异常和布格重力异常特征,并通过两条从陆架—陆坡—陆隆一直延伸到深海盆地的重力剖面拟合出地壳密度结构.研究结果表明,地壳厚度总体上从陆架、陆坡至深海平原呈现阶梯状减薄的趋势,东侧的减薄幅度大于西侧,东侧从24 km减小到10 km,西侧从21 km减小到14 km.