کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8134598 1523489 2018 19 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Quantifying widespread aqueous surface weathering on Mars: The plateaus south of Coprates Chasma
ترجمه فارسی عنوان
مقدار کافی آب و هوای سطحی در مریخ: پلاتهای جنوب کوپرات چاسما
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علوم فضا و نجوم
چکیده انگلیسی
Pedogenesis has been previously proposed on the plateaus around Coprates Chasma, Valles Marineris to explain the presence of widespread clay sequences with Al-clays and possible hydrated silica over Fe/Mg-clays on the surface of the plateaus (Le Deit et al., 2012; Carter et al., 2015). We use previous observations together with new MRO targeted observations and DEMs to constrain the extent and thickness of the plateau clay unit: the Al-clay unit is less than 3 m thick, likely ∼1 m, while the Fe/Mg-clays underneath are few tens of meters thick. We also refine the age of alteration by retrieving crater retention ages of the altered plateau and of later deposits: the observed clay sequence was created by surface pedogenesis between model ages of 4.1 Ga and 3.75 Ga. Using a leaching model from Zolotov and Mironenko (2016), we estimate the quantity of atmospheric precipitations needed to create such a clay sequence, that strongly depends on the chemistry of the precipitating fluid. A few hundreds of meters of cumulated precipitations of highly acidic fluids could explain the observed clay sequence, consistent with estimates based on late Noachian valley erosion for example (Rosenberg and Head, 2015). We show finally that the maximum quantity of sulfates potentially formed during this surface weathering event can only contribute minimally to the volume of sulfates deposited in Valles Marineris.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Icarus - Volume 302, 1 March 2018, Pages 451-469
نویسندگان
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