Biostratigraphy and Palaeogeography of the Uppermost Permian and the Lower Triassic in the Southern Realm of the Asian Teths

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The purposes of this project are summarized as follows, (1) establishment of biostratigraphy and correlation of the Upper Permian and Lower Triassic, and (2) examination of the Permian palaeobiogeography in Thailand. The surveyed areas are represented by the following three areas; namely (1) Lampang area, (2) Loei (& Chiengkan) area, and (3) Chumpon -Surasthani area. In the Lampang area the Uppermost Permian ammonoids and also the Lower Triassic ones are investigated from impure limestones and mudstones, respectively. The boundary between the Permian and Triassic is contacted by a fault in this area but the faunal break seems to be not so remarkable. In the Loei (& Chiengkan) area, the Lower Permian, Upper Carboniferous, and Devonian fossils are found from limestones and mudstones. In the Chumpon-Surasthani area Triassic corals and brachipods are investigated in the organic reef limestones. The brachiopod fauna is closely related with that of the Lampang area. Permian fusulines and Carboniferous brachiopods and pelecypods are investigated. These faunas are very important for examining the change of palaeoenvironment and palaeobiogeography in late Palaeozoic and early Mesozoic times in the southern realm of the Asian Tethys.