GR-02530; No of Pages 17 Gondwana Research 94 (2021) xxx–xxx Contents lists available at ScienceDirect Gondwana Research journal homepage: www.elsevier.com/locate/gr Peninsular Malaysia transitional geodynamic process from Gondwana to Pangaea: New constraints from 500 to 200 Ma magmatic zircon U-Pb ages and Hf isotopic compositions LongXiang Quek a,b,Yu-MingLaia,⁎, Azman A. Ghani b, Muhammad Hatta Roselee b,d, Hao-Yang Lee c, Yoshiyuki Iizuka c, Mohd Rozi Umor d,MarkPechae, Yu-Ling Lin a, Rezal Rahmat c,AzmiahJamilb a Department of Earth Sciences, National Taiwan Normal University, Taipei, Taiwan b Department of Geology, University of Malaya, Kuala Lumpur, Malaysia c Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan d Department of Earth Sciences and Environmental, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia e Arizona Laserchron Center, Department of Geosciences, University of Arizona, AZ, United States article info abstract Article history: The geodynamic process from the evolution of supercontinent has distinct isotope characteristics explorable Received 1 July 2020 using zircon Hf isotopic composition. Since Peninsular Malaysia associates with Gondwana dispersal and Pangaea Received in revised form 23 January 2021 formation, analyzing the U-Pb and Hf-isotopic content of its 500–200 Ma magmatic zircon could reveal the signal Accepted 2 March 2021 left by the transitional geodynamic process between the supercontinents. We collected two groups of magmatic Available online 05 March 2021 rocks from West Malaya: Ordovician meta-volcanics (n = 8), and Triassic Main Range granitoid province (MRGP) Editor: S. Kwon (n = 6); and three groups from East Malaya: Carboniferous meta-volcanics (n = 2), Permian-Triassic Eastern granite province (EGP) (n = 6), and Permian-Triassic EGP volcanics (n = 8). Difference in magmatic zircon Hf isotopic crustal model ages uphold the previous rationale which separates Peninsular into two blocks: West Ma- Keywords: laya (part of Sibumasu terrane) magmatic zircon Hf isotopic crustal model ages (Average TDM2: 1.3 Ga) are older Zircon U-Pb age and Hf isotope than East Malaya (part of Chanthaburi-Sukhothai-Lincang arc of Indochina terrane) (Average TDM2: 0.9 Ga). Dur- Supercontinent cycle ing the final assembly of Gondwana from 500 to 450 Ma, West Malaya and East Malaya were at the outboard of Pangaea Gondwana Proto-Tethys margin. The shift of East Malaya zircon Hf array towards higher εHf(t) (external orogenic Gondwana system) after ca.370 Ma may infers Paleo-Tethys ocean broadening and East Malaya separation from Gondwana. Peninsular Malaysia The 370–350 Ma juvenile zircon Hf isotopic composition in East Malaya is a significant improvement over radi- olarian age to show the broadening and subduction of the Paleo-Tethys ocean between the two terranes. After ca.280 Ma, East Malaya zircon Hf array shifted towards lower εHf(t) (internal orogenic system). Coinciding with the Indosinian collision at ca.230 Ma, crustal reworking signal increases in both blocks, signifying the end in Peninsular Malaysia Gondwana to Pangaea transitional geodynamic process. As the Paleo-Tethys segment was completely subducted after 230 Ma, the peninsular crustal thickening starts from 230 to 218 Ma. The post-collision phase would begin at ca.215 Ma. © 2021 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved. 1. Introduction system, supercontinent fragmentation occurs when newly formed crust (more radiogenic, hence trend towards higher εHf(t)) replaces the Two contrasting types of Earth's orogenic systems occur throughout lower crust and lithospheric mantle between two continent fragments the Phanerozoic according to zircon Hf isotope evolution: external and (Collins et al., 2011; Roberts, 2012). For the internal orogenic system, internal systems, which imitate two global-scale mantle convection supercontinent assembly consumes the interior ocean between the con- cells that drive the supercontinent cycle (Cawood et al., 2016; Collins tinental fragments through subsequent subduction. The continental et al., 2011; Murphy et al., 2009; Roberts, 2012). In the external orogenic fragments eventually collide, where a more “continental” lithosphere (less radiogenic, hence the trend towards lower εHf(t)) replaces the lower crust and lithospheric mantle underneath the overriding conti- ⁎ Corresponding author at: Department of Earth Sciences, National Taiwan Normal University, No.88, Sec. 4, Tingzhou Road, Taipei 11677, Taiwan. nent fragment (Collins et al., 2011; Roberts, 2012). Detrital and mag- E-mail address: [email protected] (Y.-M. Lai). matic zircon Hf isotopic evolution from continental fragments may https://doi.org/10.1016/j.gr.2021.03.001 1342-937X/© 2021 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved. Please cite this article as: L. Quek, Y.-M. Lai, A.A. Ghani, et al., Peninsular Malaysia transitional geodynamic process from Gondwana to Pangaea: New constraints from 5..., Gondwana Research, https://doi.org/10.1016/j.gr.2021.03.001 L. Quek, Y.-M. Lai, A.A. Ghani et al. Gondwana Research 94 (2021) xxx–xxx show the distinct characteristics of the internal and external orogenic Majority of Peninsular Malaysia magmatic rocks (Fig. 1) are Late Pa- systems which could unravel fine details regarding the continental frag- leozoic to Mesozoic and divided into three groups: (1) Permian-Triassic ment geodynamic transitional process between supercontinents. Eastern granite province (EGP) granitoid, (2) Late Triassic Main Range The idealized supercontinent cycle suggests periodicity in the timing granite province (MRGP) granitoid (Cobbing et al., 1992; Liew and of dispersal and re-amalgamation of supercontinents (Nance et al., McCulloch, 1985; Liew and Page, 1985; Liew, 1983; Ng et al., 2015a, 1988). Although the time lag between assembly and dispersal of the su- 2015b; Searle et al., 2012), and (3) Permian-Triassic EGP volcanic percontinent increase because of Earth's slowing radiogenic decay rocks. Also, we discovered two more previously unidentified groups of (Senshu et al., 2009), the general agreement is that Gondwana amal- Early and Middle Paleozoic magmatism with new field locations and gamation occurs from 640 Ma to 540 Ma, and that Pangaea formed at the aid of zircon U-Pb isotope analyses: (4) Early Carboniferous meta- around 250 Ma before its dispersal by around 200 Ma (Meert and volcanics in Langat river basin, and (5) Early to Middle Ordovician Lieberman, 2008; Roberts, 2012; Santosh et al., 2009; Senshu et al., meta-volcanics (Quek et al., 2018) in Gerik-Temenggor and Dinding 2009). Sizeable groups of continents underwent geodynamic transi- area. Because of terrain complexity, though Late Paleozoic to Mesozoic tional process from Gondwana to Pangaea during the time lag of around magmatic rocks are being actively studied from a decade ago, the 400 Ma (Roberts, 2012; Senshu et al., 2009). As Peninsular Malaysia is correlation between the magmatic suites and with the older Paleozoic free from significant post-200 Ma tectono-thermal events and associ- magmatic rocks remains poorly constrained. In this study, we present ates with the large groups of continental fragments in the geodynamic U-Pb ages (17 samples) and Hf isotope data (30 samples) on transitional process of Gondwana dispersal and Pangaea formation, its 500–200 Ma magmatic zircon from these magmatic rock groups, com- diverse magmatic rocks 500–200 Ma zircon might provide valuable iso- bined with unpublished data, aiming at delineating and improving topic evolution information regarding the geodynamic transitional (1) the Indosinian collision model of Peninsular Malaysia, (2) the evolu- process. tion of Peninsular Malaysia's Paleo-Tethys ocean segment, and (3) the Fig. 1. Simplified Peninsular Malaysia geological map showing the distribution of magmatic rocks and compiled previous studies data. Previous studies data are from Liew (1983), Liew and Page (1985), Liew and McCulloch (1985), Searle et al. (2012), Oliver et al. (2014), Ghani et al. (2014), Ng et al. (2015b), Basori et al. (2016), Jamil et al. (2016), Quek et al. (2017, 2018) and Liu et al. (2020). 2 L. Quek, Y.-M. Lai, A.A. Ghani et al. Gondwana Research 94 (2021) xxx–xxx Fig. 2. Representative cathodoluminescence (CL) images of selected zircon grains extracted from Peninsular Malaysia igneous rock. Small red circles indicate the U-Pb dating spot positions while larger blue circles indicate the spot sites of Hf isotope analyses. The circle diameters show the approximate laser spot sizes. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) transitional geodynamic process from Gondwana dispersal to Pangaea 2004). Sundaland regional tectonic is intricate and abstruse, as it is a amalgamation perceived in Peninsular Malaysia. combination of multiple small, ancient crust fragments. Peninsular Malaysia originates from two Gondwana-derived continental blocks, 2. Geological background and previous studies West Malaya (part of Sibumasu terrane) and East Malaya (linked to Chanthaburi-Sukhothai-Lincang arc of Indochina terrane) (Dodd et al., 2.1. Tectonic framework 2019; Gillespie et al., 2019; Metcalfe, 2013a, 2013b; Wang et al., 2018). During the Early Paleozoic, Proto-Tethys ocean subduction and Peninsular Malaysia which hinges by the Isthmus of Kra and lies at associated orogenic events take place