摘要
A K-rich volcano zone , Wudalianchi-Erkeshan - Keluo in Heilongjiang Province of Northeastern China , is studied in this paper . Some results from the study of mantle inclusions , accumulative inclusions and megacrysts are reported here for the first time . On the petrological , experimental , and magma-dynamical study of the host rocks and their inclusions and megacrysts , it is concluded that the K-rich magma in these areas was derived from upper mantle with rich in K2O and incompatible element by partial melting of phlogopite-bearing Iherzolite. Leucite picrite magma is primary and the magma represented by leucite basalt is derivative one of both fractional crystallization and assimilation . The mantle where the magma came from had undergone both the depletion and enrichment events , and had high geotherm similar to that of mid -oceanic ridge and rift valley . Mantle metasomatism , uplift and diapirism result in the K-rich volcanic rocks . The environment of volcanism in these areas is rift tectonics within continental plate ,and the composition and distribution of volcanic rocks in these areas are controlled by mantle-reach faults , and are not directly related to the subduction of the Pacific plate .
A K-rich volcano zone , Wudalianchi-Erkeshan - Keluo in Heilongjiang Province of Northeastern China , is studied in this paper . Some results from the study of mantle inclusions , accumulative inclusions and megacrysts are reported here for the first time . On the petrological , experimental , and magma-dynamical study of the host rocks and their inclusions and megacrysts , it is concluded that the K-rich magma in these areas was derived from upper mantle with rich in K2O and incompatible element by partial melting of phlogopite-bearing Iherzolite. Leucite picrite magma is primary and the magma represented by leucite basalt is derivative one of both fractional crystallization and assimilation . The mantle where the magma came from had undergone both the depletion and enrichment events , and had high geotherm similar to that of mid -oceanic ridge and rift valley . Mantle metasomatism , uplift and diapirism result in the K-rich volcanic rocks . The environment of volcanism in these areas is rift tectonics within continental plate ,and the composition and distribution of volcanic rocks in these areas are controlled by mantle-reach faults , and are not directly related to the subduction of the Pacific plate .
