Abstract The Eastern Ghats Belt, India, is a high grade polymetamorphic terrane; most of it was metamorphosed under high temperature to ultra-high temperature (UHT) conditions at 1000–900 Ma. This study presents new Rb–Sr biotite, 40Ar–39Ar amphibole and U–Pb rutile ages for 32 samples of HT and UHT lithologies from across the Eastern Ghats, Jaypore and Rengali Provinces. This dataset provides the first comprehensive evidence for a pervasive, region-wide amphibolite facies metamorphism at ca. 500 Ma throughout the Eastern Ghats Belt that overprinted the earlier (U)HT mineral assemblages. The lower-grade Cambrian overprint did not lead to retrogression of the high grade mineral assemblages but is recorded by different geochronometers. Rb–Sr biotite, 40Ar–39Ar amphibole and U–Pb rutile ages from the entire Eastern Ghats Belt cluster around ca. 500 Ma. U-Pb ages for zircon from six of the samples dated by Rb–Sr biotite and/or U–Pb rutile do not record this young event but yield ages that correspond to the earlier high-grade metamorphism. Combined with previously published geochronological information, the new ages show that a medium grade tectonothermal event during the Cambrian affected the whole Eastern Ghats Belt on a regional scale. This last regional metamorphism was essentially fluid-absent, as the parageneses originating from high-grade metamorphism at 1000–900 Ma are still pristine and do not show pervasive retrograde mineral reactions. This Cambrian metamorphic episode is also recorded as a high-T overprint in the high-grade gneisses of Sri Lanka, southern India and Madagascar and is the result of the assembly of Gondwana that led to the collision of Antarctica with India, which formed part of the Kuunga orogeny. The new data provide evidence for the extension of the Kuunga orogeny into eastern India and support it representing a major orogenic event in the assembly of Gondwana.

中文翻译：

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东高止山脉的 Kuunga 造山带：来自黑云母、角闪石和金红石地质年代学的证据，以及对冈瓦纳大陆组装的影响

摘要 印度东高止带是一个高品位多变质地体；大部分在1000-900 Ma的高温到超高温（UHT）条件下变质。本研究展示了来自东高止山脉、Jaypore 和 Rengali 省的 32 个 HT 和 UHT 岩性样品的新 Rb-Sr 黑云母、40Ar-39Ar 角闪石和 U-Pb 金红石年龄。该数据集提供了第一个全面的证据，证明在约 整个东高止山脉的 500 Ma 覆盖了早期的 (U)HT 矿物组合。低品位寒武纪叠印并未导致高品位矿物组合的倒退，但由不同的地质年代计记录。Rb-Sr 黑云母、40Ar-39Ar 角闪石和 U-Pb 金红石年龄来自整个东高止山脉带群约。500 马。用 Rb-Sr 黑云母和/或 U-Pb 金红石测年的六个样品的锆石 U-Pb 年龄没有记录这个年轻的事件，但产生的年龄与早期的高级变质作用相对应。结合先前公布的地质年代学信息，新纪元表明寒武纪期间的中级构造热事件在区域范围内影响了整个东高止山脉。最后一次区域变质作用基本上没有流体，因为源自 1000-900 Ma 的高级变质作用的共生岩仍然是原始的，没有表现出普遍的逆行矿物反应。这个寒武纪变质事件也被记录为斯里兰卡、印度南部和马达加斯加的高品位片麻岩中的高T叠印，是冈瓦纳大陆组装导致南极洲与印度碰撞的结果，它构成了库恩加造山运动的一部分。新数据为库恩加造山运动扩展到印度东部提供了证据，并支持它代表冈瓦纳大陆集合中的一次重大造山事件。