Academic Journal
新疆西南天山超高压变质带的形成与演化 ; The formation and tectonic evolution of UHP metamorphic belt in southwestern Tianshan, Xinjiang.
| العنوان: | 新疆西南天山超高压变质带的形成与演化 ; The formation and tectonic evolution of UHP metamorphic belt in southwestern Tianshan, Xinjiang. |
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| المؤلفون: | 张立飞, 艾永亮, 李强, 李旭平, 宋述光, 魏春景 |
| المساهمون: | 造山带与地壳演化教育部重点实验室, 北京大学地球与空间科学学院 北京100871 |
| المصدر: | 知网 ; 万方 ; SCI |
| بيانات النشر: | 岩石学报 |
| سنة النشر: | 2005 |
| المجموعة: | Peking University Institutional Repository (PKU IR) / 北京大学机构知识库 |
| مصطلحات موضوعية: | 西南天山, 超高压变质, 榴辉岩, 地球化学与年代学, 双变质带, southwestern Tianshan, UHP metamorphism, eclogite, geochemistry and geochronology, paired metamorphic belt |
| الوصف: | 本文系统地总结了近年来有关新疆西南天山超高压变质带在野外地质产状、岩石学、矿物学、地球化学和年代学等方面研究取得的进展。根据野外地质产状特征,西南天山出露的榴辉岩可以分为三类:即在蓝片岩中呈透镜体的块状榴辉岩、保存有玄武岩岩枕的枕状榴辉岩和夹杂在大理岩中的条带状榴辉岩。详细的岩石学研究表明它们都经历过超高压变质作用,其变质作用演化经历了3个阶段:峰期榴辉岩阶段(560～600℃,4.95～5.07GPa)、主期榴辉岩阶段(598～496℃,25.72～26.66±1kbar)和退变绿帘石蓝片岩相阶段。地球化学研究显示其原岩相当于源于富集地幔的(ε_(Nd)-1.4～-0.4)具有 OIB 特点. ; The recent study in geological occurrence, petrology, geochemistry and geochronology of the UHP metamorphic belt in Southwestern Tianshan has been summarized in this paper. According to their geological occurrences, the eclogites in Southwestern Tianshan can be grouped into three types, i.e., the lenticular body around by blueschist, pillow structure eclogite and banded eclogite within marble. The petrological study shows that all these three kinds eclogites have undergone ultrahigh pressure metamorphism. Their UHP metamorphic evolution can be divided into three stages: peak UHP eclogite stage with PT conditions of 560 similar to 600 degrees C and 4.95 similar to 5.07 GPa, main eclogite stage with PT conditions of 598 similar to 496 degrees C and 25.72 similar to 26.66 +/- 1 kbar and retrograde stage of epidote blueschist faces. The geochemical study suggests that the protoliths of Southwestern Tianshan eclogites should be the affinity of OIB originated from the enriched mantle with epsilon(Nd) = -1.4 similar to -0.4, NMORB from depleted mantle with epsilon(Nd) = +6.7 similar to +7.4 and EMORB from the enriched mantle with epsilon(Nd) = -2.5 similar to +3.2. The above three protoliths of eclogites may be formed in sea mountain environment. The SHRIMP dating of zircon from eclogites shows that the protoliths of eclogite were formed before Carboniferous (> 310 Ma), the oceanic subduction Tarim plate northward beneath Yili-central Tianshan Craton began in the end of Permian (280 similar to 290 Ma) and the HP-UHP metamorphism happened in Triassic (220 similar to 230 Ma). Combined with the discovery of the low pressure granulites in the north side of the UHP belt, the tectonic model based on the paired metamorphic ... |
| نوع الوثيقة: | journal/newspaper |
| اللغة: | Chinese |
| تدمد: | 1000-0569 |
| Relation: | 岩石学报.2005,(04),1029-1038.; 885139; http://hdl.handle.net/20.500.11897/235312; WOS:000232291300001 |
| DOI: | 10.3321/j.issn:1000-0569.2005.04.001 |
| الاتاحة: | https://hdl.handle.net/20.500.11897/235312 https://doi.org/10.3321/j.issn:1000-0569.2005.04.001 |
| رقم الانضمام: | edsbas.BF05C720 |
| قاعدة البيانات: | BASE |
| تدمد: | 10000569 |
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| DOI: | 10.3321/j.issn:1000-0569.2005.04.001 |