{"id":31167,"date":"2022-08-23T17:30:44","date_gmt":"2022-08-23T15:30:44","guid":{"rendered":"https:\/\/karmaka.de\/?p=31167"},"modified":"2022-08-24T11:04:22","modified_gmt":"2022-08-24T09:04:22","slug":"insight-into-the-distribution-of-high-pressure-shock-metamorphism-in-rubble-pile-asteroids","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=31167","title":{"rendered":"Insight into the Distribution of High-pressure Shock Metamorphism in Rubble-pile Asteroids<span class=\"badge-status\" style=\"background:#787878\">OPEN ACCESS<\/span>&nbsp;"},"content":{"rendered":"\n<p>Nicole G\u00fcldemeister, Juulia-Gabrielle Moreau, Tomas Kohout, Robert Luther and Kai W\u00fcnnemann<\/p>\n\n\n\n<p>The Planetary Science Journal, Volume 3, Number 8<\/p>\n\n\n\n<p><a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/PSJ\/ac83c0\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>LINK (OPEN ACCESS)<\/strong><\/a><br><a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/PSJ\/ac83c0\/pdf\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>PDF (OPEN ACCESS)<\/strong><\/a><\/p>\n\n\n\n<p>and <a rel=\"noreferrer noopener\" href=\"https:\/\/arxiv.org\/ftp\/arxiv\/papers\/2208\/2208.11006.pdf\" target=\"_blank\"><strong>PDF (OPEN ACCESS)<\/strong><\/a><\/p>\n\n\n\n<p class=\"justify-text\">&#8220;Shock metamorphism in ordinary chondrites allows for reconstructing impact events between asteroids in the main asteroid belt. Shock-darkening of ordinary chondrites occurs at the onset of complete shock melting of the rock (&gt;70 GPa) or injection of sulfide and metal melt into the cracks within solid silicates (\u223c50 GPa). Darkening of ordinary chondrites masks diagnostic silicate features observed in the reflectance spectrum of S-complex asteroids so they appear similar to C\/X-complex asteroids. In this work, we investigate the shock pressure and associated metamorphism pattern in rubble-pile asteroids at impact velocities of 4\u201310 km s\u22121. We use the iSALE shock physics code and implement two-dimensional models with simplified properties in order to quantify the influence of the following parameters on shock-darkening efficiency: impact velocity, porosity within the asteroid, impactor size, and ejection efficiency. We observe that, in rubble-pile asteroids, the velocity and size of the impactor are the constraining parameters in recording high-grade shock metamorphism. Yet, the recorded fraction of higher shock stages remains low (&lt;0.2). Varying the porosity of the boulders from 10% to 30% does not significantly affect the distribution of pressure and fraction of shock-darkened material. The pressure distribution in rubble-pile asteroids is very similar to that of monolithic asteroids with the same porosity. Thus, producing significant volumes of high-degree shocked ordinary chondrites requires strong collision events (impact velocities above 8 km s\u22121and\/or large sizes of impactors). A large amount of asteroid material escapes during an impact event (up to 90%); however, only a small portion of the escaping material is shock-darkened (6%).&#8221;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Nicole G\u00fcldemeister, Juulia-Gabrielle Moreau, Tomas Kohout, Robert Luther and Kai W\u00fcnnemann The Planetary Science Journal, Volume 3, Number 8 LINK (OPEN ACCESS)PDF (OPEN ACCESS) and PDF (OPEN ACCESS) &#8220;Shock metamorphism in ordinary chondrites allows for&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[77,7,3035,63],"tags":[3991,1807,2139,6353,6355,1673,1844,314,6354,6319],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/31167"}],"collection":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=31167"}],"version-history":[{"count":3,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/31167\/revisions"}],"predecessor-version":[{"id":31178,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/31167\/revisions\/31178"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=31167"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=31167"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=31167"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}