ABSTRACT New structural, petrographic, whole rock chemical and mineral chemical data from the Chatham Schist, the easternmost part of the Haast Schist, are presented. In combination with existing geochronological data, these bring knowledge of the basic geological framework of the Chatham Schist to the same standard as the rest of the Haast Schist. Chatham Schist is dominated by greyschist whose protoliths are correlated with the Permian-Triassic Rakaia Terrane of the Torlesse Composite Terrane. Graded bedding can be recognised in a few places in the northern Chatham Schist, but no fossils have been found. Metamorphic grade on Chatham Island is pumpellyite-actinolite facies and textural grade varies from TZ2A-3. Transitional greenschist-amphibolite facies, garnet-biotite zone Chatham Schist has been sampled in a xenolith from a Pliocene volcano and in a Southeast Chatham Terrace dredge. The age of Chatham Schist prograde metamorphism is Middle to Late Jurassic. At least two phases of penetrative deformation, and a third, brittle faulting phase, are recognised. Chatham Schist was rapidly exhumed in the late Early Cretaceous, possibly as a result of collision of the Hikurangi Plateau against the Gondwana supercontinent. Detrital garnets and spinels now found on Chatham Islands beaches were not sourced from Chatham Schist.

中文翻译：

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查塔姆片岩

摘要 介绍了来自哈斯特片岩最东端查塔姆片岩的新结构、岩相、全岩化学和矿物化学数据。结合现有的年代学数据，这些资料使查塔姆片岩的基本地质框架知识达到与哈斯特片岩其余部分相同的标准。查塔姆片岩以灰片岩为主，其原岩与 Torlesse 复合地体的二叠纪-三叠纪 Rakaia 地体相关。在查塔姆片岩北部的少数地方可以识别出分级层理，但尚未发现化石。查塔姆岛变质品位为抽水镁石-阳起石相，构造品位为TZ2A-3。过渡绿片岩-角闪岩相，石榴石-黑云母带 Chatham Schist 已在来自上新世火山和东南查塔姆台地挖泥船的捕虏体中取样。查塔姆片岩顺行变质作用时代为侏罗纪中晚期。至少识别出两个穿透变形阶段和第三个脆性断层阶段。查塔姆片岩在早白垩世晚期被迅速挖掘，可能是希库朗伊高原与冈瓦纳超大陆碰撞的结果。现在在查塔姆群岛海滩上发现的碎屑石榴石和尖晶石并非来自查塔姆片岩。可能是希库朗伊高原与冈瓦纳超大陆碰撞的结果。现在在查塔姆群岛海滩上发现的碎屑石榴石和尖晶石并非来自查塔姆片岩。可能是希库朗伊高原与冈瓦纳超大陆碰撞的结果。现在在查塔姆群岛海滩上发现的碎屑石榴石和尖晶石并非来自查塔姆片岩。