Mapping lithospheric boundaries using Os isotopes of mantle xenoliths: An example from the North China Craton
Mapping lithospheric boundaries using Os isotopes of mantle xenoliths: An example from the North China Craton
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利用地幔捕虏体的 Os 同位素绘制岩石圈边界：以华北克拉通为例
DOI：
10.1016/j.gca.2011.04.018
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发表时间：
2011-07
影响因子：
5
通讯作者：
Xu, Yi-Gang
中科院分区：
文献类型：
--
作者：
Liu, Jingao;Rudnick, Roberta L.;Walker, Richard J.;Gao, Shan;Wu, Fu-yuan;Piccoli, Philip M.;Yuan, Honglin;Xu, Wen-liang;Xu, Yi-Gang
对华北中部99个橄榄岩包体的岩石学、矿物组成、全岩常量/微量元素（包括强亲铁元素）含量和Re-Os同位素进行了测定，以确定深部岩石圈的结构和演化。七个早白垩世-第三纪火山岩中心样品自北向南表现出明显的地球化学特征。来自北方部分的橄榄岩通常更肥沃（例如，Al2O3 = 0.9 - 4.0%）比来自南方的那些（例如，Al_2O_3 = 0.2 - 2.2%），最大全岩Re-贫化Os模式年龄（TRD）为1.8Ga，表明它们形成于古元古代晚期。相比之下，南部的橄榄岩具有跨越太古代-元古代边界（2.1 - 2.5 Ga）的maximumTRD模型年龄。在北方岩群最南端的凡寺发现了两个岩群具有模型年龄的橄榄岩，这可能标志着岩石圈边界。南段岩石圈地幔的新太古代年龄与上覆地壳的年龄相吻合，可能反映了华北板块通过东西陆块碰撞合并的时间。古元古代晚期北方剖面岩石圈地幔的年龄明显小于上覆太古代地壳，表明该地区岩石圈地幔在1.8 - 1.9Ga发生于哥伦比亚超大陆组装期间的一次南北大陆-大陆碰撞中被置换，或来自于1.85Ga东西陆块碰撞过程中，北方横贯华北造山带之下孔兹岩带的1.9Ga岩石圈挤出。南部部分的后白垩纪加热由4Ma鹤壁套的橄榄岩中记录的高温（> 1000 ° C）指示，其明显高于附近早白垩世福山套的橄榄岩中记录的温度（<720 ° C），并且可能反映了早白垩世之后岩石圈的显著减薄。结合前人对华北东部地幔捕虏体的Os同位素研究结果和我们的新资料，认为岩石圈减薄和置换作用可能是由东向西演化的，在克拉通东缘始于三叠纪之前，在克拉通内部发生于侏罗纪-白垩纪，在最西边界晚于125Ma。
The petrology, mineral compositions, whole rock major/trace element concentrations, including highly siderophile elements, and Re–Os isotopes of 99 peridotite xenoliths from the central North China Craton were determined in order to constrain the structure and evolution of the deep lithosphere. Samples from seven Early Cretaceous–Tertiary volcanic centers display distinct geochemical characteristics from north to south. Peridotites from the northern section are generally more fertile (e.g., Al2O3= 0.9–4.0%) than those from the south (e.g., Al2O3= 0.2–2.2%), and have maximum whole-rock Re-depletion Os model ages (TRD) of ∼1.8 Ga suggesting their coeval formation in the latest Paleoproterozoic. By contrast, peridotites from the south have maximumTRDmodel ages that span the Archean–Proterozoic boundary (2.1–2.5 Ga). Peridotites with model ages from both groups are found at Fansi, the southernmost locality in the northern group, which likely marks a lithospheric boundary. The Neoarchean age of the lithospheric mantle in the southern section matches that of the overlying crust and likely reflects the time of amalgamation of the North China Craton via collision between the Eastern and Western blocks. The Late Paleoproterozoic (∼1.8 Ga) lithospheric mantle beneath the northern section is significantly younger than the overlying Archean crust, indicating that the original lithospheric mantle was replaced in this region, either during a major north–south continent–continent collision that occurred during assembly of the Columbia supercontinent at ∼1.8–1.9 Ga, or from extrusion of ∼1.9 Ga lithosphere from the Khondalite Belt beneath the northern Trans-North China Orogen, during the ∼1.85 Ga continental collision between Eastern and Western blocks. Post-Cretaceous heating of the southern section is indicated by high temperatures (>1000 °C) recorded in peridotites from the 4 Ma Hebi suite, which are significantly higher than the temperatures recorded in peridotites from the nearby Early Cretaceous Fushan suite (<720 °C), and likely reflects significant lithospheric thinning after the Early Cretaceous. Combining previous Os isotope results on mantle xenoliths from the eastern North China Craton with our new data, it appears that lithospheric thinning and replacement may have evolved from east to west with time, commencing before the Triassic on the eastern edge of the craton, occurring during the Jurassic–Cretaceous within the interior, and post-dating 125 Ma on the westernmost boundary.
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影响因子：
14.9
作者：
S. Shirey;R. Walker
通讯作者：
S. Shirey;R. Walker
华北克拉通汉诺坝橄榄岩捕虏体锂同位素系统学：岩石圈地幔减薄中熔岩相互作用的意义
影响因子：
5
作者：
T. Moriguti;K. Kobayashi;H. F. Zhang;E. Nakamura;Y. J. Tang;J. F. Ying
通讯作者：
J. F. Ying
影响因子：
2.7
作者：
D. Pearson;N. Wittig
通讯作者：
D. Pearson;N. Wittig
影响因子：
5
作者：
M. Rehkämper;A. Halliday;J. Fitton;Der-Chuen Lee;M. Wieneke;N. Arndt
通讯作者：
M. Rehkämper;A. Halliday;J. Fitton;Der-Chuen Lee;M. Wieneke;N. Arndt
DOI：
10.1007/978-3-642-77184-2_10
发表时间：
1993
期刊：
--
影响因子：
--
作者：
C. Gasparrini
通讯作者：
C. Gasparrini