Episodic crustal growth in the Tanzania Craton: evidence from Nd isotope compositions

• 作者: Fu-qing He Kai Sun Lei Qiu Lin-lin Zhang Sheng-fei He Xiao-dong Ren Xing-yuan Wu Zhi-dan Zhao
• 来源期刊: 中国地质（英文）
• 年，卷（期）: 2018,（2）
• 所属期刊栏目: Original Articles
• 页码范围: 210-224
• 页数: 15页
• 语种: 中文
• DOI: 10.31035/cg2018025

摘要

The analysis of available Nd isotope data from the Tanzania Craton places important constraints on the crust-mantle separation ages, and events marking juvenile crustal addition and crustal recycling. Nd model ages date the oldest crust extraction to 3.16 Ga in the Tanzania Craton, although a rock record of such antiquity is yet to be found there. The most significant period of juvenile crustal addition as well as crustal recycling is 2.7–2.6 Ga. The Nd isotopes of mafic samples show that chemical heterogeneity existed in the mantle beneath the Tanzania Craton, with some samples originating from significantly depleted mantle, and most samples originating from the mixture of primitive mantle and depleted mantle. The Nd isotope section reveals significant differences in Nd isotopes between the north craton and central craton;compared to the north craton, the central craton yields a Nd model age that is approximately 100 Ma older, and its εNd(t) values are more negative, indicating that the two parts of the craton have different mantle source regions. Different types of granitoids are distributed in the Tanzania Craton, such as high-K and low-Al granite, calc-alkaline granite, peraluminous granite and transitional types of tonalite-trondhjemite-granodiorites (TTGs). Most of the granitoids formed later than the mafic rocks in syn-collision and post-collision events.

作者信息

序号	姓名	单位	发文数	被引次数	H指数	G指数
1	Kai Sun		1	0	0.0	0.0
2	Lin-lin Zhang		1	0	0.0	0.0
3	Zhi-dan Zhao		1	0	0.0	0.0
4	Fu-qing He		1	0	0.0	0.0
5	Sheng-fei He		1	0	0.0	0.0
6	Xing-yuan Wu		1	0	0.0	0.0
7	Lei Qiu		1	0	0.0	0.0
8	Xiao-dong Ren		1	0	0.0	0.0