Evidence for a low bulk crustal density for Mars from gravity and topography
| Autor: | Gregory A. Neumann, Terence J. Sabaka, Sander Goossens, Joseph B. Nicholas, Antonio Genova, Erwan Mazarico |
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| Rok vydání: | 2017 |
| Předmět: |
Gravity (chemistry)
010504 meteorology & atmospheric sciences 01 natural sciences Article moon Physics::Geophysics polar-cap Gravitational field lunar crust grail gravity constraints thickness mission support sphere field Planet 0103 physical sciences 010303 astronomy & astrophysics 0105 earth and related environmental sciences geography geography.geographical_feature_category Resolution (electron density) Crust Mars Exploration Program Geophysics Geodesy Volcano General Earth and Planetary Sciences Terrestrial planet Astrophysics::Earth and Planetary Astrophysics Geology |
| Zdroj: | Geophysical Research Letters. 44:7686-7694 |
| ISSN: | 1944-8007 0094-8276 |
| DOI: | 10.1002/2017gl074172 |
| Popis: | Knowledge of the average density of the crust of a planet is important in determining its interior structure. The combination of high-resolution gravity and topography data has yielded a low density for the Moon’s crust, yet for other terrestrial planets the resolution of the gravity field models has hampered reasonable estimates. By using well-chosen constraints derived from topography during gravity field model determination using satellite tracking data, we show that we can robustly and independently determine the average bulk crustal density directly from the tracking data, using the admittance between topography and imperfect gravity. We find a low average bulk crustal density for Mars, 2582 ± 209 kg m−3. This bulk crustal density is lower than that assumed until now. Densities for volcanic complexes are higher, consistent with earlier estimates, implying large lateral variations in crustal density. In addition, we find indications that the crustal density increases with depth. |
| Databáze: | OpenAIRE |
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