Zircon U–Pb Geochronology, Geochemistry and Geological Significance of the Santaishan–Yingjiang Ultramafic Rocks in Western Yunnan, China

نویسندگان

چکیده

The study of ultramafic rocks in Western Yunnan is great significance for an understanding the tectonic evolution Neo-Tethys Ocean. zircon U–Pb data indicated that Santaishan serpentinized pyroxene peridotite (SSPP) was formed 186–190 Ma, and Yingjiang hornblende pyroxenite (YHP) 182–183 Ma. content MgO SSPP relatively high, but SiO2, Al2O3, CaO TiO2 ΣREE are low, while YHP has opposite characteristics. samples from have similar distribution patterns trace elements, both being enriched large ion lithophile elements (LILEs) such as Rb, Ba Th depleted high field strength (HFSEs) Ti, P Nb. These characteristics consistent with supra-subduction zone (SSZ) type mid-ocean ridge basalt (MORB) ophiolite Bangong–Nujiang suture zone. (87Sr/86Sr)i ratios (0.7091–0.7131) positive Hf(t) values (11.2–13.8), εNd(t) varying −1.1 to 9.4. low εHf(t) (3.5 6.9), Nd–Hf isotopic model ages ranging 610 942 signatures Sr–Nd Lu–Hf isotopes indicate were derived mantle, crustal material magma source may originated Neoproterozoic Rodinia supercontinent. In early Middle Jurassic (190 Ma), Tengchong Block setting active continental margin induced by subduction Ocean, where SSZ-type formed. With continuous slab retreated mantle convection, which resulted gradual thinning crust. Meanwhile, back-arc basin 183 Under influence upwelling asthenosphere mixture materials, MORB-type

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Late Palaeozoic Ultramafic Lavas in Yunnan, SW China, and their Geodynamic Significance

marine sequences within several orogenic belts in YunWe report petrological and geochemical data on ultramafic pillow nan, SW China (Figs 1 and 2; Fang et al., 1996). These lavas from Late Palaeozoic marine sequences in Yunnan, SW lavas have been interpreted to be oceanic plateaux or China. These lavas have >26 wt % MgO, euhedral to subhedral seamount eruptive rocks associated with mantle plume...

متن کامل

Unraveling alteration histories in serpentinites and associated ultramafic rocks with magnetite (U-Th)/He geochronology

Serpentinization is a widespread process that affects large-scale geodynamic processes along plate boundaries, including continental breakup, seafloor spreading, and subduction. Documenting the timing of serpentinization is critical for our understanding of these processes, but direct dating of serpentinites has been challenging or impossible. We present the first application of magnetite (U-Th...

متن کامل

petrology and geochemistry of khar-bash (western shahrood) and its relation ship to iron mineralization

منطقه مورد مطالعه در 23 کیلومتری جنوب غرب شهرستاشاهرود قرار دارد که در نقشه 100000/1 شاهرود قرار گرفته است.ناحیه مورد مطالعه در تقسیمات ساختاری ایران بخشی از زون البرز شرقی است . در طی سنوزوئیک این زون به شدت تحت تأثیر فازهای کوهزایی آلپی قرار گرفته و فعالیت های آتشفشانی انوسن در قسمت های غربی آن دیده می شود . از نظر ترکیب سنگ شناسی منطقه مورد مطالعه متنوع و بیشتر شامل سنگ های رسوبی مانند : آ...

15 صفحه اول

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Minerals

سال: 2023

ISSN: ['2075-163X']

DOI: https://doi.org/10.3390/min13040536