摘要
总结了华北中生代基性岩浆活动的年代学资料和中 -新生代岩浆的地球化学特征 ,认为岩浆随时间的演化趋势与岩石圈减薄过程密切相关。根据富集岩石圈地幔来源的岩浆作用持续时间 (180～ 90Ma)认为该区岩石圈减薄时限约为 10 0Ma。这暗示热机械侵蚀可能是华北岩石圈减薄的主要机制。华北东、西部新生代玄武岩岩浆具有相反的演化趋势 。
This paper reviews geochronological and geochemical data on Mesozoic-Cenozoic magmatism in North China. It is suggested that the temporal variation in geochemistry of Mesozoic-Cenozoic mafic rocks is coupled with lithospheric thinning process in this region. Consequently, the duration of magmatism (180～90 Ma) provides a first-order estimation for the timescale of lithospheric thinning in this region. The relatively long timescale (～100 Ma) suggests that thermomechanical erosion by convective mantle is the main mechanism of lithospheric thinning. Contrasting magmatic evolution trends in western and eastern North China craton suggest that lithospheric thinning may have proceeded in diachronous manner.
出处
《高校地质学报》
CAS
CSCD
2004年第3期324-331,共8页
Geological Journal of China Universities
基金
中国科学院百人计划项目和国家自然科学基金项目 (编号 :4 992 5 30 8)资助
关键词
年代学
地球化学
基性岩浆
热-机械侵蚀
岩石圈减薄
华北克拉通
geochronology
geochemistry
mafic magmatism
thermo-mechanic erosion
lithospheric thinning
North China Craton
