Stratigraphic and tectonic implications of Triassic conodonts from northwest Peninsular Malaysia

Abstract

AbstractThe Chuping Limestone of northwest Peninsular Malaysia, until recently considered entirely of Permian age, has yielded late Triassic (early Norian) conodonts. TheLimestone thus spans the time interval late Early Permian–Late Triassic and is in part equivalent to the Kodiang Limestone (Late Permian–Late Triassic) in Kedah andsimilar limestone sequences in south Thailand and north Sumatra. Early Late Triassic (Carnian) conodonts are also reported from pelagic limestones associated with bedded chertsof the Chert Member of the Semanggol Formation in Kedah. The Chert Member, previously considered of Middle Triassic age, is re-interpreted to represent Early, Middle and early Late Triassic deposition. The Triassic sedimentary rocks of the Malay Peninsula represent three distinct sedimentary regions: a stable shallow marine carbonate complex (ChupingLimestone, Kodiang Limestone), which forms part of an elongate carbonate platform on theSibumasu block; a deep water pelagic/turbidite basinal sequence (Semanggol Formation) which accumulated in either a foredeep basin or an intracratonic pull-apart basin related to strike-slip faulting; and a volcanic-sourced volcaniclastic basinal sequence on the East Malaya block (Semantan Formation and equivalents) which accumulated in either a forearc/intra-arc setting, or in a post-orogenic rift basin.