Full-Text Search:
Home|About CNKI|User Service|中文
Add to Favorite Get Latest Update

The Geological Environment of the Xenolith-Bearing Miocene Basalt from Siziwang County,Inner Mongolia

JING Xu,WU Tairan,HE YuankaiSchool of Earth and Space Sciences,Peking University,Beijing 100871;  
The xenolith-bearing Miocene basalts in Siziwang County,Inner Mongolia,are characterized with high-K(1.16%wt(K2O)3.36%),high-Ti(2.25%wt(TiO2)2.51%).They are enriched in light rare earth elements(LREE),high field strength elements(HFSE),highly enriched in Nb,Ta and La,and depleted in K,Rb and Ba.The parental magma was derived from a small degree melting of an asthenosphere mantle with garnet and phlogopite being the restite,and experienced a fractional crystallization of clinopyroxene and plagioclase during the magma uplifting to surface.The basalts contain xenoliths of peridotite and granulite.The peridotite xenoliths are spinel-lherzolite,which is enriched in light rare elements(LREE),with P-T conditions of 1050-1100℃ and 1.64-2.3 7GPa,representing enriched upper mantle.The granulite xenoliths are intermediate to basic composition with P-T conditions of 960-1000℃ and 0.82-1.13GPa,representing materials from lower crust or from the basic magma evolution.These indicate that the north margin of North China craton is subjected to thinning in the Miocene due to a mantle plume activity.
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©CNKI All Rights Reserved