On the origin of hot metasedimentary quartzites in the lower crust of continental arcs
文献类型：期刊论文
| 作者 | Chin, Emily J.1; Lee, Cin-Ty A.1; Tollstrup, Darren L.2; Xie, Liewen3; Wimpenny, Josh B.2; Yin, Qing-Zhu2 |
| 刊名 | EARTH AND PLANETARY SCIENCE LETTERS
 |
| 出版日期 | 2013 |
| 卷号 | 361页码:120-133 |
| 关键词 | continental arc detrital zircon granulite Sierra Nevada miogeocline passive margin |
| ISSN号 | 0012-821X |
| DOI | 10.1016/j.epsl.2012.11.031 |
| 文献子类 | Article |
| 英文摘要 | Volcanic arcs associated with subduction zones are thought to be the primary building blocks of continents. The composition of the magmas, particularly in continental arcs, is the product of mixing between differentiation of juvenile magmas and pre-existing crustal wallrock, the former being typically mafic and the latter more silicic. Because the upper continental crust is on average thought to be more silicic than the mafic lower crust, mixing with silicic endmembers should occur primarily in the upper crust. However, we show here that the lower crust of continental arcs contains silicic metasediments. We examine garnet-bearing, granulite-facies sedimentary quartzite xenoliths from the Sierra Nevada batholith in California, a Cretaceous continental arc. The quartzites have equigranular textures and contain quartz (>50%), plagioclase (<30%), garnet (10%), and small amounts (<1%) of rutile, aluminosilicate, biotite, monazite, zircon, graphite and trace orthopyroxene. Cathodoluminescent images show zircons with rounded detrital cores mantled by metamorphic overgrowths. Hf isotopic model ages and U-Pb upper intercept ages, for a given zircon, are similar, but the zircon population shows variable protolith ages ranging from Proterozoic to Archean. In contrast, all zircons share similar lower intercept U-Pb ages (103 +/- 10 Ma), which coincide with the peak of arc magmatism in the Sierra Nevada. The Precambrian protolith ages are similar to North American cratonal basement and together with the abundance of quartz and detrital zircons, suggest that these quartzites represent ancient, passive margin sediments instead of juvenile active margin sediments in the oceanic trench and accretionary prism. Importantly, these quartzites record peak metamorphic temperatures and pressures of 700-800 degrees C using Ti-in-quartz thermometry and 0.7-1.1 GPa using garnet-aluminosilicate-plagioclase thermobarometry, indicating that these xenoliths experienced significant heating and possible partial melting in the lower crust, most likely related to arc magmatism as suggested by similarities between the lower intercept U-Pb ages and the ages of plutonism in the Sierra Nevada. Possible mechanisms by which these sediments were transported into the lower crust include continental underthrusting beneath the continental arc, underplating by buoyant slab-derived sedimentary diapirs, or viscous downflow of country rock in response to diapiric ascent of plutons. Continental underthrusting has been independently documented during the Sevier orogeny, coinciding with the peak of arc magmatism. We thus speculate that supracrustal rocks may have been underthrusted into deep crustal magmatic zones. Regardless of how these metasediments arrived in the lower crust, our observations indicate that silicic metasediments occur in the lower crust of volcanic arcs, not just in the upper crust as is commonly thought. Transport of metasediments into deep crustal magmatic zones should influence the composition of arc magmas and continental crust in general. (C) 2012 Elsevier B.V. All rights reserved. |
| WOS关键词 | SIERRA-NEVADA BATHOLITH ; U-PB GEOCHRONOLOGY ; LU-HF ; ZIRCON GEOCHRONOLOGY ; CALIFORNIA ; BENEATH ; ROCKS ; MANTLE ; CONSTRAINTS ; MAGMATISM |
| WOS研究方向 | Geochemistry & Geophysics |
| 语种 | 英语 |
| WOS记录号 | WOS:000314907000014 |
| 出版者 | ELSEVIER SCIENCE BV |
| 资助机构 | NSF EAR(1119315) ; NSF EAR(1119315) ; University of California Davis ; University of California Davis ; NASA(NNG05GN03G ; NASA(NNG05GN03G ; State Key Laboratory of Lithospheric Evolution, IGG-CAS(Z201003 ; State Key Laboratory of Lithospheric Evolution, IGG-CAS(Z201003 ; NNX08AG57G) ; NNX08AG57G) ; Z0802) ; Z0802) ; NSF EAR(1119315) ; NSF EAR(1119315) ; University of California Davis ; University of California Davis ; NASA(NNG05GN03G ; NASA(NNG05GN03G ; State Key Laboratory of Lithospheric Evolution, IGG-CAS(Z201003 ; State Key Laboratory of Lithospheric Evolution, IGG-CAS(Z201003 ; NNX08AG57G) ; NNX08AG57G) ; Z0802) ; Z0802) ; NSF EAR(1119315) ; NSF EAR(1119315) ; University of California Davis ; University of California Davis ; NASA(NNG05GN03G ; NASA(NNG05GN03G ; State Key Laboratory of Lithospheric Evolution, IGG-CAS(Z201003 ; State Key Laboratory of Lithospheric Evolution, IGG-CAS(Z201003 ; NNX08AG57G) ; NNX08AG57G) ; Z0802) ; Z0802) ; NSF EAR(1119315) ; NSF EAR(1119315) ; University of California Davis ; University of California Davis ; NASA(NNG05GN03G ; NASA(NNG05GN03G ; State Key Laboratory of Lithospheric Evolution, IGG-CAS(Z201003 ; State Key Laboratory of Lithospheric Evolution, IGG-CAS(Z201003 ; NNX08AG57G) ; NNX08AG57G) ; Z0802) ; Z0802) |
| 源URL | [http://ir.iggcas.ac.cn/handle/132A11/87020]  |
| 专题 | 中国科学院地质与地球物理研究所 |
| 通讯作者 | Chin, Emily J. |
| 作者单位 | 1.Rice Univ, Dept Earth Sci, Houston, TX 77005 USA 2.Univ Calif Davis, Dept Geol, Davis, CA 95616 USA 3.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China |
| 推荐引用方式 GB/T 7714 | Chin, Emily J.,Lee, Cin-Ty A.,Tollstrup, Darren L.,et al. On the origin of hot metasedimentary quartzites in the lower crust of continental arcs[J]. EARTH AND PLANETARY SCIENCE LETTERS,2013,361:120-133. |
| APA | Chin, Emily J.,Lee, Cin-Ty A.,Tollstrup, Darren L.,Xie, Liewen,Wimpenny, Josh B.,&Yin, Qing-Zhu.(2013).On the origin of hot metasedimentary quartzites in the lower crust of continental arcs.EARTH AND PLANETARY SCIENCE LETTERS,361,120-133. |
| MLA | Chin, Emily J.,et al."On the origin of hot metasedimentary quartzites in the lower crust of continental arcs".EARTH AND PLANETARY SCIENCE LETTERS 361(2013):120-133. |
入库方式： OAI收割
来源：地质与地球物理研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。