UHT granulites of the Highland Complex, Sri Lanka I: Geological and petrological background
UHT granulites of the Highland Complex, Sri Lanka I: Geological and petrological background
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DOI：
10.2465/jmps.151227
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发表时间：
2016-07
影响因子：
0.7
通讯作者：
Y. Osanai;K. Sajeev;N. Nakano;Ippei Kitano;W. Kehelpannala;Ryosuke Kato;T. Adachi;S. Malaviarachchi
中科院分区：
文献类型：
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作者：
Y. Osanai;K. Sajeev;N. Nakano;Ippei Kitano;W. Kehelpannala;Ryosuke Kato;T. Adachi;S. Malaviarachchi
斯里兰卡的超高温（UHT）区域变质作用在理解冈瓦纳超大陆的构造和形成方面具有重要作用。斯里兰卡特别重要，因为它位于冈瓦纳的中心位置，位于印度南部，马达加斯加和南极洲东部之间。特别是，高地杂岩一直是几个以前的研究的重点，因为突出的变质沉积岩，经历了超高温变质。斯里兰卡中部高原杂岩由含Spr-bearing富镁铝麻粒岩与其他泥质，镁铁质麻粒岩和钙硅酸盐，其中保存了几个超高温变质的结构证据。计算的镁铝富麻粒岩的峰变质条件产生的温度范围从910到1005摄氏度在1.0 GPa，和压力之间变化0.9至1.2 GPa。估算的变质P-T条件和演化路径与前人的研究以及马达加斯加南部、印度南部和东南极洲的类似岩石类型的研究结果相吻合。
The ultrahigh-temperature (UHT) regional metamorphism of Sri Lanka has a significant role in understanding the tectonics and formation of the Gondwana supercontinent. Sri Lanka is specifically important because of its central position in Gondwana, located between southern India, Madagascar and eastern Antarctica. In particular, the Highland Complex has been the focus of several previous studies because of the prominence of metasedimentary rocks that experienced UHT metamorphism. The central Highland Complex of Sri Lanka consists of Spr-bearing Mg-Al rich granulites intercalated with other pelitic, mafic granulites and calc-silicates, which preserve several textural evidences for UHT metamorphism. The calculated peak metamorphic conditions for the Mg-Al rich granulite yielded a temperature range from 910 to 1005 degrees C at 1.0 GPa, and the pressure varies between 0.9 to 1.2 GPa. The estimated metamorphic P-T conditions and evolution path is in good agreement with previous studies and also to that of similar rock-types from southern Madagascar, southern India and East Antarctica.