Lower crustal xenoliths from Junan, Shandong province and their bearing on the nature of the lower crust beneath the North China Craton
Lower crustal xenoliths from Junan, Shandong province and their bearing on the nature of the lower crust beneath the North China Craton
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山东莒南下地壳捕虏体及其对华北克拉通下地壳性质的影响
DOI：
10.1016/j.lithos.2010.07.015
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发表时间：
2010-10
期刊：
影响因子：
3.5
通讯作者：
汤艳杰
中科院分区：
文献类型：
--
作者：
英基丰,张宏福;汤艳杰
对中国东部山东省莒南市晚白垩世玄武岩角砾岩脉中的麻粒岩捕虏体进行了年代学、岩石学和地球化学研究。这些捕虏体在矿物学和块体岩石成分方面与华北克拉通南缘女山麻粒岩捕虏体和太古代麻粒岩地形非常相似，但与华北克拉通北部哈诺巴镁铁质麻粒岩捕虏体有很大不同。原位锆石 U-Pb 年龄和 Hf 同位素分析以及地球化学数据表明，这些捕虏体的原岩形成于大约 2.3Ga 前，通过镁铁质岩浆的同化-分步结晶而形成。这些捕虏体的P-T条件表明莒南地区下地壳的深度可达35km，这与各种地球物理方法推论的结果非常吻合。这些捕虏体的岩石学和地震莫霍面深度、观测到的速度结构和计算出的速度一致，表明不存在底侵诱发的壳幔过渡带，而该过渡带在华北克拉通北部形成良好。与早侏罗世下地壳深度40~50km相比，晚白垩世莒南地区下地壳深度延伸至30km，表明华北克拉通下地壳在晚中生代显着减薄。
Geochronological, petrological and geochemical studies were performed on the granulite xenoliths from a Late Cretaceous basaltic breccia dike in Junan, Shandong province, eastern China. These xenoliths show close similarities to the Nushan granulite xenoliths from the southern margin of the North China Craton (NCC) and the Archean granulite terrains in terms of mineralogy and bulk rock compositions, but are quite different from the Hanuoba mafic granulite xenoliths from the northern NCC. In-situ zircon U–Pb age and Hf isotopic analyses, together with geochemical data reveal that the protolith of these xenoliths was formed around 2.3Ga ago, through assimilation–fractional crystallization of a mafic magma. P–T conditions of these xenoliths suggest that the lower crust beneath the Junan region reaches to a depth of 35km, which agree well with the result deduced from various geophysical methods. The consistent petrological and seismic Moho depths, the observed velocity structure and calculated velocity of these xenoliths imply the absence of underplating induced crust–mantle transition zone, which was well formed in the northern NCC. Compared to 40–50km depth of the lower crust in Early Jurassic, the lower crust beneath Junan extended to a depth of 30km in Late Cretaceous, suggesting that the lower crust of NCC was significantly thinned during Late Mesozoic.
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影响因子：
3.9
作者：
S. Klemme;D. Günther;K. Hametner;Stefan Prowatke;T. Zack
通讯作者：
S. Klemme;D. Günther;K. Hametner;Stefan Prowatke;T. Zack
影响因子：
5.8
作者：
A. Draut;P. Clift
通讯作者：
A. Draut;P. Clift
DOI：
10.1002/cjg2.884
发表时间：
2006-05
期刊：
Chinese Journal of Geophysics
影响因子：
--
作者：
Zhiwei Li;Yi Xu;T. Hao;Jin‐Song Liu;Ling Zhang
通讯作者：
Zhiwei Li;Yi Xu;T. Hao;Jin‐Song Liu;Ling Zhang
影响因子：
--
作者：
L. Shuguang;Yang Wei
通讯作者：
L. Shuguang;Yang Wei
影响因子：
5
作者：
Yongsheng Liu;Shan Gao;Shuyan Jin;Shenghong Hu;M. Sun;Zu-Bin Zhao;Jiaqing Feng
通讯作者：
Yongsheng Liu;Shan Gao;Shuyan Jin;Shenghong Hu;M. Sun;Zu-Bin Zhao;Jiaqing Feng