“…Quantifying the metamorphic character of an eclogite facies region and its areal distribution has received extensive attention because of clear documentation of subduction‐ or collision‐related metamorphism, and a subsequent exhumation process at plate convergent margins (e.g., Hacker, ; Katayama, Zayachkovsky, & Maruyama, ; Medaris, Fournelle, Ghent, Jelínek, & Mísař, ; Sobolev, Shatsky, Vavilov, & Goryaynov, ). Eclogites and eclogite facies rocks in many HP metamorphic belts occur as lenses, boudins, bodies, layers, or nappes in various scales within surrounding country rocks, and show definite differences between their metamorphic conditions and those of country rocks (e.g., Clarke, Aitchison, & Cluzel, ; Fitzherbert, Clarke, & Powell, ; Krogh, Andresen, Bryhni, Broks, & Kristensen, ; Tsujimori, Matsumoto, Wakabayashi, & Liou, ; Vitale Brovarone & Agard, ; Wallis & Aoya, ). Determining whether or not country rock once experienced eclogite facies metamorphism along with the enclosed HP rock depends on the presence of index HP minerals (e.g., omphacite, jadeite).…”