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Palaeozoic correlations and the palaeogeography of the Sibumasu (Shan-Thai) Terrane - a brief review |
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| รหัสดีโอไอ | |
| Creator | Clive Burrett, Mongkol Udchachon and Hathaithip Thassanapak |
| Title | Palaeozoic correlations and the palaeogeography of the Sibumasu (Shan-Thai) Terrane - a brief review |
| Publisher | Mahasarakham University |
| Publication Year | 2559 |
| Journal Title | Research & Knowledge |
| Journal Vol. | 2 |
| Journal No. | 2 |
| Page no. | 1-17 |
| Keyword | Thailand, Malaysia, Yunnan, Ordovician, Devonian, biostratigraphy, palaeogeography |
| ISSN | 2408-204x |
| Abstract | Furongian sandstones yield shallow-water trilobite faunas along the length of the SibumasuTerrane in the four regions of NW Malaysia (Langkawi), southern Thailand (Satun), the Shan Statesof Myanmar and the Baoshan Block of western Yunnan. These are associated with felsic plutonics,volcanics or volcaniclastics in all four regions. Correlations of Langkawi Island and Satun Provinceshallow-water carbonates reveal a succession of dominantly molluscan, stromatoporoid-brachiopodfaunas which, from conodont evidence, range from the mid-Tremadocian to the Darriwilian, and whichhave dominantly North China-Australian affinities. A major increase in sea-level in the late Darriwilianled to trilobite-brachiopod faunas with very strong South China affinities. Deep-water conditions ofmore than 150 m prevailed in the Katian with the deposition of red, stromatolitic limestones with cool/deep-water trilobite and conodont faunas. This 'Pa Kae facies' re-occurs in limestones of Silurian andDevonian age in several areas of Sibumasu. Llandovery graptolitic shales occur along the length of theterrane. Silurian, probably outer shelf, limestones occur in NW Malaysia, the Shan States and Baoshanbut have a limited distribution in Thailand. Most Katian to Devonian faunas in NW Malaysia, Thailandand Baoshan show evidence of deep-water deposition which continues into the Mississippian of NWMalaysia and into the Pennsylvanian of Thailand contrasting with the Baoshan Block's extensive,Devonian to Mississippian shallow-water, coral-rich carbonates.A significant mid-Carboniferous to Pennsylvanian depositional gap in the Shan States andBaoshan may be due to regional uplift by the mantle plume that triggered Cisuralian rifting ofSibumasu from Gondwana. Palaeomagnetic results from Baoshan, along with biogeographic evidenceand provenance data from Thailand show that Sibumasu was definitely part of the Australian sector ofGondwana until the Cisuralian and did not experience major deformation until Late Triassic collisionwith Indochina. |
