Geochemistry and Tectonic Significance of Late Mesozoic Intrusive Rock in Xiaoshan-Zhuji Region, Northwest Zhejiang Province
详细信息
- 责任者：Xie Huaisheng (Geological Survey Institute of Zhejiang Province ; Hangzhou 311203 ; China) ; Zhang Jianfang
- 刊名：Contributions to Geology and Mineral Resources Research
- 出版年：2013
- 卷期：28(3)
- 关键词：花岗闪长岩 ; granodiorites ; 闪长岩 ; diorites ; 浙江 ; Zhejiang Province
- 页码：p.424-433
- 图表：6 illus., 2 tables, 29 refs.
- 分类号：0801
- issnNo：ISSN1001-1412
- isbnNo：CN12-1131/P
摘要
The Late Jurassic granite(quartz)diorite and Early Cretaceous(pyroxene)diorite are geochmically characterized by low silicon,poor in alkaline,rich in Ca,Mg,Fe,weak negative Eu anomaly,rightward REE curve,enrichment of K,Rb,Ba,Th,U,depletion of Nb,Ta,less depletion of Sr,Ti.The late granite of Late Jurassic Epoch and late granite(porphyry)of Cretaceous Epoch share the geochemical characteristics of high Si,enrichment of alkalis,poor in Ca,and Mg,strong negative Eu anomaly,.However,the former is characterized by the "V" type REE distribution patterns,and strong enrichment of K,Rb,Th,U,relative rich in Nb,Ta,strong depletion of Ba,Sr,Ti.etc.And the latter by the rightward REE curve,enrichment of K,Rb,Th,U,and depletion of Nb,Ta,Sr,Ti,but no depletion of Ba.Petrological,geotectonic and geochemical plots show that the diagenetic tectonic environment of the type I-A intrusive rock at the end of the late Jurassic evolved from the subduction extrusion collision to post-collision or post-orogeny.At end of the late Early Cretaceous the highly differentiated type Igranite is closely related to the volcanic-sub-volcanic eruption-intrusion.The diagenetic tectonic setting is mainly related to regional extension.