Geophysical and petrological applications of new-generation satellite-derived gravity data: What can and needs to be done?

New-generation satellite-derived gravity and gradient data from CHAMP, GRACE and, in particular, GOCE will be especially useful for studies of the Earth's crust and upper mantle. The advantage of these new models is that they provide gravity information (1) for areas previously lacking data and (2) that is continuous and consistent across natural and artificial boundaries. However, before the new satellite gravity and gradient data are applied to geophysical applications, new methods must be developed and tested. In particular, methods are required for dealing with the computation of Bouguer anomalies. The resolving power of the satellite gravity must also be quantified in order to ascertain the degree to which the satellite data resolves lithospheric structures. This can be achieved by comparing the satellite data to gravity and gradients predicted from existing 3D density models. Another test of the satellite-derived data is to compare it to the gravity field predicted by independently-determined density models that use new petrologicallyand thermodynamically-based methods. Potential applications of the new satellite data in studies of the crust and upper mantle are numerous. The long-wavelength nature of the satellite gravity data mean that they may be useful for regional-residual field separation. New density models constrained by satellite data will extend existing interpretations and provide new insight into frontier regions where little or no surface data exist. In subduction zones, static density modelling and finite-element modelling can be used to study asperities and to examine the temporal variation of the gravity field in response to fore-arc deformation.