Discovery of coesite in the North Qaidam Early Palaeozoic ultrahigh pressure (UHP) metamorphic belt, NW China

作者：Yang JS^*; Xu ZQ; Song SG; Zhang JX; Wu CL; Shi RD; Li HB; Brunel M

来源：Comptes Rendus - Academie des Sciences, Serie II: Sciences de la Terre, et des Planetes , 2001, 333(11): 719-724.

DOI：10.1016/S1251-8050(01)01718-9

• UHP metamorphism
• coesite
• eclogite
• Qinghai-Tibet plateau
• North Qaidam Mt

Coesite and graphite were discovered as inclusions in zircon separates from pelitic gneiss associated with a large eclogite body in the North Qaidam UHP terrane. This finding suggests UHP metamorphism at pressures below the diamond stability field. This supports previous indirect UHP evidences, such as polycrystalline quartz inclusions in eclogitic garnet, quartz lamellae in omphacite and P-T estimates for both eclogite and garnet peridotite. The U/Pb and Sm/Nd isotopic ages from the North Qaidam eclogite indicated that continental subduction occurred in Early Palaeozoic, most probably in relation with the collision between the Sino-Korean and Yangtze plates.

• 出版日期2001-12-15
• 单位中国地质科学院