Geophysics of the Pacific Basin

摘要: Gravity anomalies show the effects of both topography solid earth and its compensation. Free-air gravity anomalies, therefore, approximately represent isostatic small range free-air about 800 mgal (1 = 10-5 m sec-2), or 0.08% earth’s field, shows that is nearly in equilibrium (Bowin et al., 1982). Large-amplitude deviations from isostasy, are maintained by tectonic activities (Vening Meinesz, 1932). Isostasy fairly well achieved wavelengths longer than 500 km Pacific basin, corresponding as ±20 (McKenzie 1980). The value 20 0.002% indicates measurements need high precision. It was difficult for prealtimeter field to discuss such because spatial resolution data obtained satellite orbit perturbations not sufficient, surface observations were sparse free measurement errors ±10 mgal.