Satellite gravity gradient grids for geophysics
نویسندگان
چکیده
The Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite aimed at determining the Earth's mean gravity field. GOCE delivered gravity gradients containing directional information, which are complicated to use because of their error characteristics and because they are given in a rotating instrument frame indirectly related to the Earth. We compute gravity gradients in grids at 225 km and 255 km altitude above the reference ellipsoid corresponding to the GOCE nominal and lower orbit phases respectively, and find that the grids may contain additional high-frequency content compared with GOCE-based global models. We discuss the gradient sensitivity for crustal depth slices using a 3D lithospheric model of the North-East Atlantic region, which shows that the depth sensitivity differs from gradient to gradient. In addition, the relative signal power for the individual gradient component changes comparing the 225 km and 255 km grids, implying that using all components at different heights reduces parameter uncertainties in geophysical modelling. Furthermore, since gravity gradients contain complementary information to gravity, we foresee the use of the grids in a wide range of applications from lithospheric modelling to studies on dynamic topography, and glacial isostatic adjustment, to bedrock geometry determination under ice sheets.
منابع مشابه
Fault Strike Detection Using Satellite Gravity Data Decomposition by Discrete Wavelets: A Case Study from Iran
Estimating the gravity anomaly causative bodies boundary can facilitate the gravity field interpretation. In this paper, 2D discrete wavelet transform (DWT) is employed as a method to delineate the boundary of the gravity anomaly sources. Hence, the GRACE’ satellite gravity data is decomposed using DWT. DWT decomposites a single approximation coefficients into four distinct components: the appr...
متن کاملMarine gravity anomaly from Geosat and ERS 1 satellite altimetry
Closely spaced satellite altimeter profiles collected during the Geosat Geodetic Mission (-6 km) and the ERS 1 Geodetic Phase (8 km) are easily converted to grids of vertical gravity gradient and gravity anomaly. The long-wavelength radial orbit error is suppressed below the noise level of the altimeter by taking the along-track derivative of each profile. Ascending and descending slope profile...
متن کاملLunar Sub - Surface Objects Using Surface Gravimetric Surveys
Introduction: Surface gravity surveying is a well developed terrestrial geophysical technique, used to detect subsurface density variations, which in turn can reveal subsurface geologic features. Here we perform a feasibility study to determine what major science questions can be answered by a rover-mounted, highly compact gravimeter and gravity gradiometer being designed by Gedex Inc.; a Toron...
متن کاملThe basalt geometry in the west siberian basin from satellite gravity, magnetics and seismics
Adding new value to Electromagnetic, Gravity and Magnetic Methods for Exploration Capri, Italy, April 11-14, 2010 The basalt geometry in the west siberian basin from satellite gravity, magnetics and seismics S. Ferrante(), C. Braitenberg (), J. Ebbing () () Dipartimento di Geoscienze, Università di Trieste, Trieste, Italy( ), Geological Survey of Norway (NGU), Trondheim, Norway, and Department...
متن کاملInterpretation of gravity anomalies via terracing method of the profile curvature
One of the main goals of interpretation of gravity data is to detect location and edges of the anomalies. Edge detection of gravity anomalies is carried out by different methods. Terracing of the data is one of the approaches that help the interpreter to achieve appropriate results of edge detection. This goal becomes a complex task when the gravity anomalies have smooth borders due to gradual ...
متن کامل