海洋大地水准面的多尺度分析

利用径向基函数多尺度分析方法,将GOCO05S模型海洋大地水准面分解为3个尺度,并进行详细的分析统计。分解后重构的大地水准面精度达到了±0.02m,表明了径向基函数出色的多尺度分析能力。对不同深度层面上大地水准面异常的分布及成因做了深入探讨。浅层上地幔大地水准面异常主要分布于板块边缘,呈条状,与火山热点源分布类似;深层上地幔大地水准面异常和大洋中脊所在位置部分吻合,主要呈带状或块状,与上地幔的对流有关;中间层上地幔的大地水准面异常形态介于上述两者之间,主要受火山热点源和地幔对流的综合影响。

Multi-scale Analysis of Marine Geoid

Using radial basis function multiscale analysis method,the global marine geoid is decomposed into three scales successfully.The accuracy of reconstructed signal reaches about ±0.02m,which indicates a good ability of radial basis functions in multi-scale modeling of the gravity field.The distribution and cause of geoid anomalies in different layer of upper mantle are discussed.The geoid anomalies produced by the shallower layer mainly locate on the plate boundary,which are very similar to the distribution of volcanic hot spots.The geoid anomalies generated by deeper layer,however,coincide with the midocean ridge,showing a striking correlation with the mantle plume convection.Due to the combined effect of volcanic hot spot source and mantle convection,the distribution of the geoid anomalies caused by the middle layer of upper mantle is relatively scattered.