Geochemistry and provenance of Mesozoic sandstones in Khon Kaen Geopark: Implication for tectonics of the western Khorat Plateau of Thailand

Vimoltip Singtuen; Burapha Phajuy; Apussorn Anumart; Punya Charusiri; Natnicha Chawthai; Heiner Heggemann

doi:10.1371/journal.pone.0284974

Geochemistry and provenance of Mesozoic sandstones in Khon Kaen Geopark: Implication for tectonics of the western Khorat Plateau of Thailand

PLoS One. 2023 Apr 26;18(4):e0284974. doi: 10.1371/journal.pone.0284974. eCollection 2023.

Authors

Vimoltip Singtuen¹, Burapha Phajuy², Apussorn Anumart¹, Punya Charusiri^{3

4}, Natnicha Chawthai¹, Heiner Heggemann⁵

Affiliations

¹ Department of Geotechnology, Faculty of Technology, Khon Kaen University, Khon Kaen, Thailand.
² Department of Geological Sciences, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand.
³ Department of Mineral Resources, Ministry of Natural Resources and Environment, Bangkok, Thailand.
⁴ MESA CE, Faculty of Science, Chulalongkorn University, Bangkok, Thailand.
⁵ Hessisches Landesamt für Naturschutz, Umwelt und Geologie, Wiesbaden, Germany.

Abstract

Khon Kaen Geopark, representing an area of dinosaur fossil diversity, was selected for investigations to reveal the origin and tectonic setting of the Khorat Group. The area occupied by Mesozoic sedimentary rocks of four formal formations of the Khorat Group, namely the Phra Wihan Formation (PWF), Sao Khua Formation (SKF), Phu Phan Formation (PPF), and Khok Kruat Formation (KKF). A field investigation and macroscopic observations suggested that the immature sedimentary rocks of the study area are mainly clast-supported, pebbly sandstone and siltstone with few calcretes. The 50 rock samples that were selected for petrographical and geochemical investigations revealed that the sandstones of the PWF and PPF are quartz arenite and sublitharenite, with some subarkose, whereas those of the SKF are mainly subarkose and sublitharenite. In addition, the KKF dominantly presents sublitharenite with pebbles and calcretes. Mesozoic sandstones contain quartz, feldspars, various types of rock fragments, and accessory minerals (biotite, muscovite, zircon, and tourmaline), with siliceous, ferrous, and calcareous cement. Petrographic (Q-F-L) and geochemical (major and trace element) data suggested that the sources of sediments are mostly quartzose sedimentary rocks and some felsic-intermediate igneous rocks. Chondrite-normalized rare earth element patterns indicated that the origins of the studied sandstones are quartzose sedimentary rocks deposited in a passive continental margin or an upper continental crust. Geochemical traits of the sedimentary successions demonstrated that the provenance of the Khorat Basin prior to reworking by fluvial processes was situated in the passive continental margin or recycled orogen of the paleo-volcanic arc during the Mesozoic period.

Copyright: © 2023 Singtuen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Fossils
Geologic Sediments*
Minerals
Quartz*
Thailand

Substances

Quartz
Minerals

Grants and funding

This work is a part of research on the Potential to Enhance the Geotourism of Khon Kaen National Geopark, conducted by the Department of Geotechnology, Khon Kaen University, and received funding support from the National Science Research and Innovation Fund (NSRF) of Thailand under Grant 161719 (Fundamental Fund). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.