{"id":25763,"date":"2021-01-22T12:54:43","date_gmt":"2021-01-22T11:54:43","guid":{"rendered":"http:\/\/karmaka.de\/?p=25763"},"modified":"2021-01-22T12:54:44","modified_gmt":"2021-01-22T11:54:44","slug":"poirierite-a-dense-metastable-polymorph-of-magnesium-iron-silicate-in-shocked-meteorites","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=25763","title":{"rendered":"Poirierite, a dense metastable polymorph of magnesium iron silicate in shocked meteorites<span class=\"badge-status\" style=\"background:#787878\">OPEN ACCESS<\/span>&nbsp;"},"content":{"rendered":"\n<p>Naotaka Tomioka, Luca Bindi, Takuo Okuchi, Masaaki Miyahara, Toshiaki Iitaka, Zhi Li, Tsutomu Kawatsu, Xiande Xie, Narangoo Purevjav, Riho Tani &amp; Yu Kodama<\/p>\n\n\n\n<p>Communications Earth &amp; Environment 2 , 1\u20138<\/p>\n\n\n\n<p><a href=\"https:\/\/www.nature.com\/articles\/s43247-020-00090-7\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>LINK (OPEN ACCESS)<\/strong><\/a><br><a href=\"https:\/\/www.nature.com\/articles\/s43247-020-00090-7.pdf\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>PDF (OPEN ACCESS)<\/strong><\/a><\/p>\n\n\n\n<p class=\"justify-text\">&#8220;A dense magnesium iron silicate polymorph with a structure intermediate between olivine, ringwoodite, and wadsleyite was theoretically predicted about four decades ago. As this group of minerals constitute the major component of shocked meteorites, constraining their transitional forms and behaviour is of potential importance for understanding impact events on their parent bodies. Here we use high-resolution transmission electron microscopy techniques and single-crystal X-ray diffraction analyses to identify naturally occurring examples of this mineral \u2013 recently named poirierite \u2013 in shocked chondritic meteorites. We observe nanoscale lamellar poirierite topotactically intergrown within wadsleyite, and additionally within ringwoodite as recently reported. Our results confirm the intermediate structure of poirierite and suggest it might be a relay point in the shear transformations between its polymorphs. We propose that poirierite formed during rapid decompression at relatively low temperature in retrograde shock metamorphism of the meteorites.&#8221;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Naotaka Tomioka, Luca Bindi, Takuo Okuchi, Masaaki Miyahara, Toshiaki Iitaka, Zhi Li, Tsutomu Kawatsu, Xiande Xie, Narangoo Purevjav, Riho Tani &amp; Yu Kodama Communications Earth &amp; Environment 2 , 1\u20138 LINK (OPEN ACCESS)PDF (OPEN ACCESS)&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6,23,7,63],"tags":[5819,1807,5818,1844,1274,2656],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/25763"}],"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=25763"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/25763\/revisions"}],"predecessor-version":[{"id":25764,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/25763\/revisions\/25764"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=25763"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=25763"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=25763"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}