摘要
近年来在鲁西地区早前寒武纪结晶基底进行锆石SHRIMP测年结果显示,泰山岩群形成年龄大约在2770~2750Ma。新太古代发生3期岩浆侵入活动,每期岩浆侵入活动开始都有地幔岩浆侵入。早期构造岩浆活动主要形成2740~2700Ma的英云闪长质片麻岩、条带状英云闪长质片麻岩;中期构造岩浆活动主要形成2650~2600Ma的TTG质花岗岩;晚期构造岩浆活动最强烈,从地幔岩浆侵入到地壳深熔形成大规模的钾质花岗岩,导致大规模陆壳的形成。古元古代早期和中元古代,有少量岩浆沿太古代刚性陆壳裂解形成的张性裂隙侵入。对鲁西地区前寒武纪侵入岩按岩性+时代进行了重新划分,变质深成侵入体(片麻岩)按时代+gn,依据其不同成分和不同结构构造的第一个英文大写字母进行表示,探讨了鲁西地区早前寒武纪陆壳演化历史。
As showed by zinc SHRIMP chronometric age result of early Cambrian crystalline basememt in Luxi area, the forming age of Taishan group is in about 2750Ma. Tonalitic gneiss and belt type tonalitic gneiss with the age of 2.7Ga was formed in the first period of magmatic movement, TTG granites with the age of 2.6 Ga was formed in the second tectonic magmatic movement period, and medium basic rock - medium acid intrusive rock with the age of 2.55 -2.5Ga were formed in the third tectonic magmatic period. From magma intrusion in mantle to large scale of kaligranite melting, large scale of crust were formed. A little of magma intruded along extensive crack which was formed by Archaean stiff crust cracking. According to rock property and age, early Cambrian intrusive rocks in Luxi area are classified again, and evolution history of early Cambrian crust in Luxi area is studied as well in this paper.
出处
《山东国土资源》
2008年第1期10-20,共11页
Shandong Land and Resources
关键词
早前寒武纪
地质研究
新进展
鲁西地区
Early Cambrian
geological study
advanced developement
Luxi area