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Detailed Reference Information
Marsh et al. 1981
Marsh, J.G., Marsh, B.D., Williamson, R.G. and Wells, W.T. (1981). The gravity field in the central Pacific from satellite-to-satellite tracking. Journal of Geophysical Research 86: doi: 10.1029/JB086iB05p03979. issn: 0148-0227.

Satellite-to-satellite Doppler tracking between the ATS 6 and the GEOS 3 spacecraft is used to measure the high-degree and -order gravity field over an 80¿ area in the central Pacific Ocean. Doppler tracking provides velocity measurements of GEOS 3 as a function of time, which are easily converted to line-of-sight accelerations. Since the low-degree and -order gravity field is known well, each GEOS 3 revolution is reduced relative to a twelfth-degree and -order field model. The method is then capable of measuring wavelengths in the range from about 3500 to 1000 km. Accelerations computed along 40 revolutions roughly half of them descending and the others ascending, can be contoured into a gap of the gravity field at the GEOS 3 altitude of 840 km. The dominant wavelength of the map is about 2000 km. A comparison of this field with an altimeter-derived geoid and the GEM 10B gravity field shows good agreement. Since each map is essentially independent of the others, this comparison is critical in establishing the validity of any of the maps. Each map shows virtually the same areas of positive and negative anomalies. These areas are essentially the same in the central Pacific as those found in our earlier study. Compared with surface amplitudes these anomalies are only one-tenth as large as the GEOS 3 altitude. This observation and the correlation of gravity with residual depth anomalies imply that the cause of some of these anomalies may be due to bumps in the upper surface of the lithosphere that are compensated at depths of about 30-100 km. Some of the anomalies apparently do not correlate with residual depth anomalies.

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Journal of Geophysical Research
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