C. S. Hutchison and S. P. Sivam write: Harbury et al ‘ s 1990 paper is a useful contribution to our knowledge of the Mesozoic Tembeling Formation. However, the generalizations on stratigraphy and orogenesis for the whole Peninsular Malaysia are based on inadequate literature research and a general unfamiliarity with the region. Accordingly we feel obliged to bring to your attention the most obvious shortcomings of the paper.
The timing of the Indosinian Orogeny of Southeast Asia (Belov et al. 1986) traditionally was based on the widespread elimination of marine sedimention and general uplift by early Jurassic time. The predominantly Carnian-Norian strata (collectively called Upper Triassic flysch), were followed by predominantly Jurassic-Cretaceous molasse: the characteristically red Tembeling Group (Malaysia) and the Terrain Rouge (Indochina), and the non-oxidized Gagau Group and Tebak Formation (Malaysia) and the Grès Supérieurs of Indochina. The critical locality in Peninsular Malaysia is at Jengka Pass, where the gently dipping marine Tembeling Formation is late Triassic to early Jurassic, unconformably underlain by vertically bedded Late Permian limestone, shale and sandstone (Ichikawa et al. 1966). This situation is an analogue of the western margin of the Khorat Basin of NE Thailand, where the Upper Triassic to earliest Jurassic Huai Hin Lat Formation unconformably overlies late Permian Saraburi Limestone (Kon’no & Asama 1973). Jurassic redbeds succeed the Huai Hin Lat Formation, and in Peninsular Malaysia the marine Jengka Pass sequence is succeeded eastwards by continental redbed facies.
The information of the foregoing paragraph has been distorted by Harbury et