Comparison of Observed and Predicted Gravity Profiles Over Aphrodite Terra, Venus
نویسندگان
چکیده
We compare observed Pioneer Venus orbiter (PVO) gravity profiles over Aphrodite Terra to profiles predicted from models of thermal isostasy, mantle convection, and Airy compensation. Similar approaches are used in order to investigate how well the models can be distinguished with the PVO data. Topography profiles across Aphrodite are compared to model spreading ridge profiles in order to further assess this model. Airy compensation depths and convection layer thicknesses are greater under eastem Aphrodite than western Aphrodite. Compensation depths in the east are greater than most estimates of lithospheric thickness, uggesting that this part of the ridge is dynamically supported. In parts of westem Aphrodite, the spreading ridge model gravity provides a better fit to the data than either Airy compensation orman fie convection. Best-fit spreading rates are between 0.3 and 1.6 cm/yr. Airy compensation a d mantle convection cannot be distinguished in most places using only PVO data.
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