Abstract The Middle Triassic Pulau Ayer Chawan Formation is a predominantly deep-marine, occasionally shallow-marine sedimentary succession, deposited in the Singapore sector of the Palaeo-Tethyan Semantan Basin. The formation provides an important record of the dynamic interplay between a siliciclastic sedimentary system and the products of an adjacent active volcanic arc. It is characterised by six sub-environments, including: deep-marine turbidite fan, deep-marine background sedimentation, subaqueous debris cone, shallow-marine, volcanically-sourced turbidite fan, and hyaloclastite mound or ridge. Turbidite fan deposits preserve the input of both siliciclastic and volcaniclastic sediments from the shelf, transported into the deep-marine environment by a suite of subaqueous sediment gravity flow processes, including: turbidity currents; mixed flow types (hybrid event beds); concentrated and hyper concentrated sediment gravity flows, and debris flows. Thick heterolithic successions of debrites were likely sourced through regular collapse of an unstable shelf. The presence of hybrid event beds, encountered within the deep-marine turbidite fans, supports a slope that was out-of-grade, and may have been actively retreating towards the hinterland. Together, these factors suggest regional-scale uplift of the eastern margins of the Semantan Basin during Triassic times, most likely facilitated through volcanic activity in the adjacent Palaeo-Tethys Sukhothai Arc. Evidence for contemporaneous, arc-related magmatism includes ubiquitous volcaniclastic sedimentary rocks within formation, including pyroclastic density current deposits and perhaps more-strikingly through the hyaloclastites of the Nanyang Member. The hyaloclastites formed through quenching of magmas delivered into the deep-marine setting from a series of sub-sea vents or mounds.

中文翻译：

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新加坡中三叠世古特提斯森曼丹盆地深至浅海沉积学和火山作用的影响

摘要 中三叠世 Pulau Ayer Chawan 组是一个以深海为主，偶尔为浅海沉积序列，沉积在古特提斯森曼丹盆地的新加坡段。该地层提供了硅质碎屑沉积系统与相邻活动火山弧产物之间动态相互作用的重要记录。它具有六个亚环境特征，包括：深海浊积扇、深海背景沉积、水下碎屑锥、浅海、火山源浊积扇和透明碎屑岩丘或山脊。浊积扇沉积物保留了来自陆架的硅质碎屑和火山碎屑沉积物的输入，通过一系列水下沉积物重力流过程输送到深海环境，包括： 浊流；混合流类型（混合事件床）；集中和超集中沉积物重力流和泥石流。厚厚的异岩系列碎片很可能来自不稳定的陆架的定期坍塌。在深海浊流扇中遇到的混合事件床的存在支持了一个不合等级的斜坡，并且可能一直在积极地向内陆撤退。总之，这些因素表明三叠纪期间 Semantan 盆地东部边缘区域规模的隆升，最有可能是通过邻近的古特提斯 Sukhothai 弧的火山活动促进的。与弧相关的同期岩浆活动的证据包括地层中无处不在的火山碎屑沉积岩，包括火山碎屑密度电流沉积物，也许更引人注目的是通过南洋段的玻璃碎屑岩。通过从一系列海底喷口或土丘输送到深海环境中的岩浆淬火形成透明碎屑岩。