Limited migration and nearly in-situ redistribution of non-conservative elements in retrograde Sulu ultrahigh pressure eclogites

作者：Zeng LingSeng^*; Zhang ZeMing; Liu FuLai; Liang FengHua

来源：Acta Petrologica Sinica, 2007, 23(12): 3215-3220.

• non-conservative element
• eclogite
• amphibolite
• retrograded metamorphism
• Sulu UHP belt

Mafic rocks from the Chinese Continental Scientific Drilling (CCSD) project consist of fresh eclogites as well as amphibolites. These amphibolites were resulted from various degrees of retrograde metamorphic reactions of fresh eclogites during their en route to the surface. Bulk major and trace element data show that they have similar geochemistry in Rb, Cs, Sr, and Ba, even though these elements are extremely mobile in the presence of aqueous fluids. Such fluids were essential to retrograde reactions that led to the transformation of fresh eclogites into amphibolites. The nearly identical geochemical nature in these non-conservative elements between these mafic rocks demonstrates that (1) limited and restricted fluids during the exhumation of UHP eclogites in the Sulu UHP metamorphic belt; and (2) nearly in-situ redistribution of highly mobile elements. This conclusion is also in good agreement with those reached from studies on the stable isotope geochemistry, fluid inclusion, and structure of Sulu UHP rocks.

• 出版日期2007-12
• 单位中国地质科学院