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Transition between the Thabsila metamorphic complex and the Lower Paleozoic formations and their sandstone provenance, Kanchanaburi, western Thailand |
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| รหัสดีโอไอ | |
| Creator | Sirot Salyapongse |
| Title | Transition between the Thabsila metamorphic complex and the Lower Paleozoic formations and their sandstone provenance, Kanchanaburi, western Thailand |
| Contributor | Praipada Santadgarn, Panus Hong, Suwijai Jatupornkongchai, Ekkachak Chandon, Prinya Putthapiban |
| Publisher | Department of Mineral Resources of Thailand |
| Publication Year | 2563 |
| Journal Title | Thai Geoscience Journal |
| Journal Vol. | 1 |
| Journal No. | 1 |
| Page no. | 28-49 |
| Keyword | regional metamorphism, sandstone provenance, Cambrian, Ordovician |
| URL Website | http://www.dmr.go.th/index_.php, https://tgjdmr2019.wixsite.com/mysite, https://tgjdmr2019.wixsite.com/mysite/download-article |
| Website title | กรมทรัพยากรธรณี, THAI GEOSCIENCE JOURNAL |
| Abstract | In Kanchanaburi province western Thailand, the oldest three rock units include the Thabsila metamorphic complex exposed side by side with the Cambrian Chao Nen and the Ordovician Tha Manao formations, possessing field relation, petrography and geochemistry strongly suggesting a transitional relationship. The latter two rock formations are equivalent to the Cambrian Tarutao Group and the Ordovician Thung Song Group from southern Thailand. They are characterized by alternating lithofacies of argillites, siliciclastics and carbonates. The gradational nature among them both in lithology and grade of metamorphism with only a single mode of foliation development indicates one episode of progressive regional metamorphism. Modal compositions of the Upper Thabsila and the Chao Nen meta-siliciclastic sandstones show they were original quartz arenite and subarkose to arkosic sandstones. Their provenance was from a continental block setting. The chemical discrimination diagrams indicate they were deposited in a passive continental margin environment and have an asymmetrically cyclic sedimentation habit. This evidence implies that there is no unconformity between the Thabsila complex and the Lower Paleozoic formations. Although this terrain was subjected to a series of northwest dextral strike-slip fault movement, their gradational nature in grades of metamorphism is, in part of some sections, still preserved. Their sharing of the same provenance and the tectonic setting show that they were continuously deposited throughout the long history of the Shan-Thai terrane (up to as young as around Carboniferous, the timing of tectonically uplifting by the incoming of volcanism to this terrane). The underlying older Precambrian basement, the source rock of the Thabsila complex have never been observed and probably have been re-melted to the common foliated Triassic S-type granite in western Thailand. |
