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对东准噶尔北部地区侵入于中泥盆世北塔山组地层的希勒克特哈腊苏花岗闪长斑岩和喀腊萨依二长闪长斑岩的锆石SHRIMPU-Pb定年结果表明,其形成时代分别为(381±6)和(376±10)Ma,代表俯冲过程形成的花岗质岩石,这是该地区迄今为止首次报道的位于350~390Ma的花岗质岩石的同位素年龄.喀腊萨依二长闪长斑岩锆石的另一组年龄(408±9Ma)可能代表了其下部下泥盆统火山岩的时代.同时,同位素测年结果暗示了准噶尔洋由南西向北东俯冲过程的时间间隔可能为408~376Ma(实际间隔间隔可能要略大一些).由于含矿斑岩是在中泥盆世北塔山组火山岩形成后不久侵位的,因此本区与产出有世界级斑岩铜矿的安第斯山的构造背景相似,具有形成大型斑岩铜矿的成矿潜力.
The zircon SHRIMPU-Pb dating of the Shleketha-Hallasu granodiorite porphyry and the kalasayi monzonitic porphyry in the northern part of East Junggar, which invaded the Beitashan formation of the Middle Devonian, The formation ages are (381 ± 6) and (376 ± 10) Ma, respectively, representing granitic rocks formed during subduction. This is the first isotopic age of granitic rocks located in 350 ~ 390 Ma in the area so far reported. Another group of ages (408 ± 9Ma) of the Ganshayi dioritic porphyry zircon may represent the age of the Lower Devonian volcanic rocks, and the isotopic dating results suggest that the Junggar Ocean from southwest to north The time interval of the subduction process may be 408 ~ 376Ma (the actual intervals may be slightly larger.) Since the ore-bearing porphyries emplaced shortly after the volcanic rocks of the North Tashan Formation in the Middle Devonian, The Andean Porphyry copper deposits have similar tectonic settings and have the potential for forming large porphyry copper deposits.