https://scholars.lib.ntu.edu.tw/handle/123456789/37361
標題: | 西北蘇門答臘碎屑鋯石鈾鉛定年與鉿同位素研究 Detrital Zircon U-Pb and Hf Isotopic Study in Northwestern Sumatra, Indonesia |
作者: | 許鈞傑 Hsu, Chun-Chieh |
關鍵字: | 碎屑鋯石;鈾鉛定年;鉿同位素;蘇門答臘;Detrital zircon;U-Pb dating;Hf isotope;Sumatra | 公開日期: | 2016 | 摘要: | In NW Sumatra, Tertiary sedimentary basins that occur in forearc and backarc settings with respect to the present-day subduction system were deposited in three major terranes, namely, the Woyla Nappe, the East Sumatra block, and the West Sumatra block. NW Sumatra represents the product of complex accretion/collision/subduction histories among these three terranes, which have originated from the eastern margin of Gondwanaland. To better understand the complex histories, we present a detrital zircon study in NW Sumatra that, together with our unpublished work on major magmatic rocks in the area, allow us to reach the following conclusions: (1) Detrital zircons from 14 samples (river sand or sandstone) in the forearc basin reveal seven age peaks at ~1050 Ma (n=74), ~550 Ma (n=65), ~214 Ma (n=138), ~131 Ma (n=14), ~100 Ma (n=65), ~52 Ma (n=238) and 17-0 Ma (n=303), respectively; (2) Detrital zircons from nine samples in the backarc basin show similar age populations; (3) The Late Triassic zircons, with εHf(T) values of -18 to 0, are sourced mainly from the Indosinian granitoids that are widespread in the East Sumatra block; (4) The less abundant Early Cretaceous zircons, with εHf(T) values of -5 to 0, are most likely from the West Sumatra block; (5) The Late Cretaceous zircons, with εHf(T) values of +11 to +16, are from the Woyla Nappe due probably to the Woyla accretion; (6) The Eocene and younger zircons, with εHf(T) values of +6 to +17, are from the initial stage and modern arc magmatic rocks related to the Indian Ocean plate subduction. |
URI: | http://ntur.lib.ntu.edu.tw//handle/246246/273074 | DOI: | 10.6342/NTU201601696 | Rights: | 論文公開時間: 2016/8/3 論文使用權限: 同意有償授權(權利金給回饋本人) |
顯示於: | 地質科學系 |
檔案 | 描述 | 大小 | 格式 | |
---|---|---|---|---|
ntu-105-R03224101-1.pdf | 23.54 kB | Adobe PDF | 檢視/開啟 |
在 IR 系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。