地质学报(英文版)
地質學報(英文版)
지질학보(영문판)
ACTA GEOLOGICA SINICA
2002年
1期
81-88
,共8页
王涛%郑亚东%李天兵%高永军%马铭波
王濤%鄭亞東%李天兵%高永軍%馬銘波
왕도%정아동%리천병%고영군%마명파
granitic pluton%forceful emplacement%extension%Yagan-Onch Hayrhan
It is generally considered that granitic plutons are forcefully emplaced in a compressional setting and permissively emplaced in an extensional setting. This paper, however, shows that syn-kinematic (extensional) elliptic granitic plutons in the Yagan-Onch Hayrhan metamorphic core complex (MCC) have relatively strong forceful emplacement, which are indicated by (1) concentric distribution of the rock units, (2) a strain pattern with strong strains on the margins and low strains at the centre of a pluton, and particularly (3) syn-emplacement shortening of the host rocks within the aureole. The strain analysis for the host rocks shows that the host-rock ductile shortening, I.e. Forceful emplacement, provides about 16?24% of the emplacement space for the present plutons. All these suggest that forceful emplacement occurs not only in a compressional tectonic setting, but also in an extensional setting. This study further demonstrates the significance of the multiple emplacement of granitic plutons and provides new information about the causality between granitic magmatism and the formation of the MCC and its dynamics.