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岩石学报 2010
New constraints on formation ages of ophiolites in northern Junggar and comparative study on their connection
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Abstract:
There exist Kujibai ophiolite in Taerbahatai, Hongguleleng-Hebukesaier ophiolite and Zhaheba-Aermantai ophiolite in northern Junggar. The SHRIMP zircon U-Pb dating of cumulate gabbro in Hongguleleng ophiolite is 472±8.4Ma (MSWD=1.4) and the zircon U-Pb age of plagioclase granite in Zhaheba ophiolite is 495.9±5.5Ma (MSWD=2.7). Taerbahatai ophiolite, Hongguleleng-Hebukesaier ophiolite and Zhaheba-Aermantai ophiolite had been formed before Early Ordovician and mostly emplaced in Devonian-Carboniferous volcanic sedimentary strata along faults. A comparative study on formation age, regional geology and geophysical characteristics of these three segments of ophiolites in northern Junggar indicates that they are correlated as a unique ophiolite belt passing through from east to west in northern Junggar. This study is significant for the reconstruction of Paleozoic tectonic framework and regional tectonic evolution.