The role of target strength on the ejection of martian meteorites

Our collection of meteorites recovered here on Earth contain over 200 samples believed to have originated Mars. It is commonly accepted that these rocks were launched as ejecta during the formation impact craters. The majority are young and basaltic representing only a small fraction martian surface. Previous studies examined impacts into basalt or other competent material, but material bias remains unexplained. In this study we define fragmentation parameters for dry tuff, proxy weakly cemented regolith sedimentary covering much We simulate hypervelocity surface using joint Eulerian-Lagrangian shock physics code. A wide parameter search conducted impactor sizes ranging from 10 meter kilometers in radius. find tuff produces significantly smaller fragments than all sizes. Maximum fragment size amount ejected scale with size. also examine mixed targets, mainly simple layers embedded boulders. layer overtop inhibits ejection, while enhances ejection increases Boulders create complex pressure field near-surface region, relatively unchanged.