کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6431173 | 1634944 | 2006 | 8 صفحه PDF | دانلود رایگان |
Eclogites in central Qiangtang, northern Tibet (China) are characterized by the garnet + omphacite + rutile + phengite + quartz assemblage. Hornblende, plagioclase, and sphene occur as retrograde amphibolite facies phases in the eclogites. Pressure-temperature estimates for the primary eclogite assemblage are consistent with minimum pressures of 20-25 kbar at 482 to 625 °C. The retrograde amphibolite facies assemblage suggests conditions of 10-12 kbar and 460-600 °C. Consequently, the eclogites from central Qiangtang have undergone unambiguous ultrahigh- pressure (UHP) metamorphism. The presence of UHP metamorphic rocks implies a likely deep-seated continental subduction along the Shuanghu suture within the Qiangtang terrain. The denudation of these UHP metamorphic rocks correlates well with the main interval that the Songpan-Ganzi turbidites accumulated and could have provided a significant source for these sedimentary rocks.
Journal: Earth and Planetary Science Letters - Volume 245, Issues 3â4, 30 May 2006, Pages 722-729