1.39 Ga mafic dyke swarm in southwestern Yilgarn Craton marks Nuna to Rodinia transition in the West Australian Craton
1.39 Ga mafic dyke swarm in southwestern Yilgarn Craton marks Nuna to Rodinia transition in the West Australian Craton
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DOI：
10.1016/j.precamres.2018.08.014
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发表时间：
2018-10
影响因子：
3.8
通讯作者：
J. Stark;Xuan‐Ce Wang;Zheng‐Xiang Li;S. Denyszyn;B. Rasmussen;Jian-Wei Zi
中科院分区：
文献类型：
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作者：
J. Stark;Xuan‐Ce Wang;Zheng‐Xiang Li;S. Denyszyn;B. Rasmussen;Jian-Wei Zi
西澳大利亚太古代伊尔加恩克拉通至少发育了从太古宙到新元古代的五代基性岩脉，包括约2408年 Ma Widgiemooltha和1210年 Ma Marnda Moorn大火成岩省（LIP），西南部1888年 Ma Boonadgin岩脉和北部1075年 Ma Warakurna岩脉。本文报道了在伊尔甘克拉通西南部新发现的nnw走向的基性岩脉群，命名为Biberkine岩脉群，根据bad - leite的ID-TIMS U-Pb年代学测定时间为1390 ± 3 Ma。岩脉群的区域范围尚不确定，但航磁资料表明，岩脉群是数百公里长的线状岩脉群的一部分，被南部的中元古代奥尔巴尼-弗雷泽造山带截断。地球化学资料表明，岩脉具有拉斑岩成分，主要来自交代富集的次大陆岩石圈地幔和（或）下大陆地壳。古地理重建表明，约1600 Ma以来伊尔冈克拉通的长时间构造静止被1400 Ma左右沿南部和东南部边缘的重新俯冲所打断，反映了从努纳到罗迪尼亚构造的过渡。1390年 Ma Biberkine岩脉可能是这种转变的直接结果，标志着从被动构造环境到活动构造环境的转变，这种转变在1330 Ma左右的奥尔巴-弗雷泽造山运动中达到高潮。Biberkine岩脉群与世界上许多其他基性岩脉群处于同一时期，为古地磁研究提供了一个重要的研究对象。
The Archean Yilgarn Craton in Western Australia hosts at least five generations of mafic dykes ranging from Archean to Neoproterozoic in age, including the craton-wide ca. 2408 Ma Widgiemooltha and the 1210 Ma Marnda Moorn Large Igneous Provinces (LIP), the 1888 Ma Boonadgin dykes in the southwest and the 1075 Ma Warakurna LIP in the northern part of the craton. We report here a newly identified NNW-trending mafic dyke swarm, here named the Biberkine dyke swarm, in the southwestern Yilgarn Craton dated at 1390 ± 3 Ma by ID-TIMS U-Pb geochronology of baddeleyite. The regional extent of the dyke swarm is uncertain but aeromagnetic data suggest that the dykes are part of a linear swarm several hundred kilometers long, truncated by the Mesoproterozoic Albany-Fraser Orogen to the south. Geochemical data indicate that the dykes have tholeiitic compositions with a significant contribution from metasomatically enriched subcontinental lithospheric mantle and/or lower continental crust. Paleogeographic reconstructions suggest that a prolonged tectonic quiescence in the Yilgarn Craton from ca. 1600 Ma was interrupted by renewed subduction along the southern and southeastern margin at ca. 1400 Ma, reflecting a transition from Nuna to Rodinia configuration. The 1390 Ma Biberkine dykes may be a direct consequence of this transition and mark the change from a passive to active tectonic setting, which culminated in the Albany-Fraser Orogeny at ca. 1330 Ma. The Biberkine dykes are coeval with a number of other mafic dyke swarms worldwide and provide an important target for paleomagnetic studies.