Wang, Yuejun and Liu, Zi and Murtadha, Sayed and Cawood, Peter A. and Qian, Xin and Ghani, Azman Abd and Gan, Chengshi and Zhang, Yuzhi and Wang, Yang and Li, Shan and Zhang, Peizhen (2022) Jurassic subduction of the Paleo-Pacific plate in Southeast Asia: New insights from the igneous and sedimentary rocks in West Borneo. Journal of Asian Earth Sciences, 232. ISSN 1367-9120, DOI https://doi.org/10.1016/j.jseaes.2022.105111.
Full text not available from this repository.Abstract
The tectonic affinity of West Borneo and its relationship with the East Asia continental margin are key issues for unraveling SE Asia tectonics. New zircon U-Pb and Hf-O isotopes and whole-rock elemental and Sr-Nd-Pb isotopic data of the igneous and associated sedimentary rocks in West Borneo document the development of Early (\~200-185 Ma) and Late (\~160-145 Ma) Jurassic arc-like igneous rocks. In the Kuching Zone and South Schwaner Mountains, the Jurassic mafic-intermediate igneous rocks are characterized by enrichment in LILEs, depletion in HFSEs, epsilon(Hf)(t) = +0.6 - +11.6, delta O-18 = 4.97-5.61 parts per thousand, epsilon(Nd)(t) =-2.5\~+2.4, (Pb-206/Pb-204)i = 18.71-19.37 and (Pb-208/Pb-204)i = 38.75-39.58. They originated from a sediment-modified mantle wedge source in a supra-subduction zone setting. The Jurassic granitoids shared consistent elemental and Sr-Nd-Pb-Hf-O isotopic signatures with epsilon(Hf)(t) = +1.7\~+15.6, delta O-18 = 4.97-6.01 parts per thousand, epsilon(Nd)(t) =-1.1\~ +4.2, with delta 8/4 = 22.5-51.9 and delta 7/4 = 5.8-14.3, arguing for a juvenile crust-dominated origin. Detritus from the associated sedimentary rocks in the Kuching Zone and South Schwaner Mountains was largely derived from the nearby Jurassic magmatic arc. Their detrital zircon age patterns are comparable to those from the East Malaysia-Indochina and Sibu zone, but distinctive from those in SE Borneo. Integrating all data with those from regional surveys, the igneous and sedimentary rocks in the South Schwaner Mountains are suggested to commence in the earliest Jurassic or even Triassic. West Borneo might be the eastward extension of the Triassic Sundaland. The western Kuching Zone and western South Schwaner Mountains represent the southmost part of the active Jurassic Andean-type East Asian continental margin. The westward subduction of the paleo-Pacific plate was initiated around the earliest Jurassic at \~200 Ma or ea
| Item Type: | Article |
|---|---|
| Funders: | Australian Research Council [Grant no. FL160100168], National Natural Science Foundation of China [Grant no. 41830211, U1701641], Natural Science Foundation of Guangdong Province [Grant no. 2016ZT06N331, 2018B030312007, 2019B1515120019] |
| Uncontrolled Keywords: | East Asia Andean-type continental margin; Elements and isotopes; Jurassic igneous rocks; Paleo-Pacific subduction; Sedimentary provenance; West Borneo |
| Subjects: | Q Science > QE Geology |
| Divisions: | Faculty of Science > Department of Geology |
| Depositing User: | Ms. Juhaida Abd Rahim |
| Date Deposited: | 04 Jun 2025 07:16 |
| Last Modified: | 04 Jun 2025 07:16 |
| URI: | http://eprints.um.edu.my/id/eprint/42166 |
Actions (login required)
 |
View Item |
