[1] The analysis of seismic data represents today the primary tool in the search for the presence of postperovskite in the lowermost mantle (D00). This work aims at testing whether the inversion of gravitational data can also contribute to the detection of postperovskite in D00. We assume that the transition from perovskite to postperovskite is accompanied by a reduction in viscosity and test t...

The performance of Gravity field and steady-state Ocean Circulation Explorer (GOCE) global gravity field models (GGMs), at the end of GOCE mission covering 42 months, is evaluated using geoid undulations and free-air gravity anomalies over Japan, including six sub-regions (Hokkaido, north Honshu, central Honshu, west Honshu, Shikoku and Kyushu). Seventeen GOCE-based GGMs are evaluated and compa...

The GEOSA T spacecraft was launched into a retrograde orbit from the Western Test Range in March 1985. The first 18 months were dedicated to completing the high-resolution mapping of the marine geoid undertaken by the Seasat mission in 1978 and interrupted by its early demise. In September 1986, the spacecraft was maneuvered into an orbit more suited for oceanography. That phase of the mission ...

Introduction: Crater distribution on Venus indicates that the surface has undergone global-scale resurfacing in a short period of time [1]. Determining the timing of events has been difficult due to the near-random crater pattern. Some progress has been made in the relative dating of various types of features [2,3,4]. In addition, current deformation of Venus' surface has been described as a sw...

This article summarises some considerations surrounding a geoid-model-based vertical datum that have to be thought through before its implementation and adoption. Our examples are based on many Australian and some South-East Asian experiences, but these probably also apply elsewhere. Thekey considerations comprisedataquality andavailability, politics, anddifficulties thatusersmayencounterwhen a...

a back propagation artificial neural network (bpann) is a well-known learning algorithmpredicated on a gradient descent method that minimizes the square error involving the networkoutput and the goal of output values. in this study, 261 gps/leveling and 8869 gravity intensityvalues of iran were selected, then the geoid with three methods “ellipsoidal stokes integral”,“bpann”, and “collocation” ...

Many features of the oceanic plates cannot be explained by conductive cooling with age. A number of these anomalies require additional convective thermal sources at depths below the plate: mid-plate swells, the evolution of fracture zones, the mean depth and heat flow relationships with age and the observation of small scale (150-250 km) geoid and topography anomalies in the Central Pacific and...