کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1773910 1021151 2012 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Impact airblast triggers dust avalanches on Mars
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علوم فضا و نجوم
پیش نمایش صفحه اول مقاله
Impact airblast triggers dust avalanches on Mars
چکیده انگلیسی

Visible images from the Mars Reconnaissance Orbiter have revealed more than 200 new impact sites on Mars (almost all in dust-mantled regions) containing 1–50 m diameter craters, often in clusters. We count approximately 65,000 small-scale slope streaks within 2 to 3 km of one such cluster and categorize them into four morphologically distinct types. Here we show that these slope streaks (interpreted as dust avalanches) are triggered by the impact event but, surprisingly, are not due to seismic shaking; instead, the dust avalanches are due to airblasts created by the supersonic meteor(s) before impact. Sixteen of the new impact sites are associated with high areal densities of dust avalanches. The observed dust avalanche frequency suggests that impact-generated airblasts constitute a locally important and previously unrecognized process for inducing slope degradation on Mars.


► Some of the recent small impacts on Mars cause 103–105 20 m dust avalanches.
► There are two temporally distinct avalanche types: impact-induced and pre-impact.
► Surprisingly, impact airblasts, not seismic shaking, trigger the avalanches.
► The impact-affected area is enormous: about 106 times larger than the crater sizes.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Icarus - Volume 217, Issue 1, January 2012, Pages 194–201
نویسندگان
, , , , , ,