کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
8134121 | 1523482 | 2018 | 31 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Ancient selenophysical structure of the Grimaldi basin: Constraints from GRAIL gravity and LOLA topography
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
موضوعات مرتبط
مهندسی و علوم پایه
علوم زمین و سیارات
علوم فضا و نجوم
پیش نمایش صفحه اول مقاله

چکیده انگلیسی
The Grimaldi impact basin is located near the western limb of the moon and lies to the southwest of the Oceanus Procellarum. A clearly visible positive gravity anomaly exists in its low-lying inner wall, implying a subsurface mass concentration beneath the crater. Exploration of this basin could extend our meaningful and fundamental understanding of giant impact processes as well as the structure of mare basins/craters. Limited by the low-resolution of previous gravity field models, it was once impossible to explore the structure beneath Grimaldi. The recent high-resolution gravity data from the Gravity Recovery and Interior Laboratory mission make it possible to break through this barrier. Prior to our investigation of the selenophysical structure around crater Grimaldi, we developed a flexure model that includes surface and subsurface loads. A localized admittance analysis was performed by combining high-resolution gravity data with the high-resolution topography data obtained from Lunar Orbiter Laser Altimeter. Within 2ÏSTD error constraints, we estimated the best-fit parameters over Grimaldi as well as two other places in its neighborhood. All the predicted admittances show a goodness of fit with their corresponding observations. The large load ratio (â¼9.2) found at the Grimaldi is an indirect mirror of the dominant subsurface load, consistent with its large positive gravity anomaly in its low-lying floor. Not only the crustal thickness of 48â¯km but also the crustal density of 2500 kg mâ3 found around Grimaldi shows a great accordance with the recent results of GRAIL. Given the best-fit parameters of f, bc and Ïc, the elastic thickness Te is found to be around 28â¯km over Grimaldi. Taking into account the best-fit values in its neighborhood, a regional elastic thickness of 30â¯km could be roughly concluded around Grimaldi, which is completely in the previous ranges (20â¯<â¯Te<â¯60â¯km) from Clementine. Our result of the elastic thickness is quite larger than those on the lunar nearside volcanic complexes of the recent GRAIL study. Considering fewer thermal activities occurred on the lunar limb or farside than its nearside, we can then deduce that the lithosphere could be possibly cold and therefore developed a corresponding dense elastic thickness.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Icarus - Volume 309, 15 July 2018, Pages 411-421
Journal: Icarus - Volume 309, 15 July 2018, Pages 411-421
نویسندگان
Zhen Zhong, Jianguo Yan, J. Alexis P. Rodriguez, James M. Dohm,