Petrology and geochemistry of igneous rocks from southern Tioman Island, Pahang, Peninsular Malaysia


Author : Muhammad Hatta Roselee, Azman A. Ghani & Rozi UmorPublication : Bulletin of the Geological Society of MalaysiaVolume : 62Page : 79 - 89Year : 2016


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Bulletin of the Geological Society of Malaysia, Volume 62, December 2016, pp. 79 – 89

Petrology and geochemistry of igneous rocks from southern Tioman Island, Pahang, Peninsular Malaysia

Muhammad Hatta Roselee1,2,*, Azman A. Ghani1 & Mohd Rozi Umor2

1Department of Geology, Faculty of Science, University Malaya, 50603 Kuala Lumpur
2Geology Programme, School of Environmental and Natural Resources, Faculty of Science and Technology,
National University of Malaysia, 43600 Bangi, Selangor
*Corresponding author: hattarosley@yahoo.com

Abstract: This study reports on the petrology and geochemistry of the plutonic and volcanic on southern part of the Tioman Island. Tioman lies about 50km east of Rompin district, Pahang. The island is dominated by plutonic and volcanic rocks with minor occurrences of metamorphic rock. The plutonic rocks consist of hornblende diorite and biotite granite. The hornblende diorite shows differences in mineralogy and geochemistry when compared to the main diorite body. The volcanics are mostly rhyolite and dacite with exception of andesite on other part of the island. Metamorphic rocks include the andalusite hornfels, quartz pyroxene hornfels, quartzite and amphibolite. Field relationships and published geochronological results indicates that the granite rock intruded both volcanic and diorite rocks during the Late Cretaceous (~80 Ma).The biotite granite post-dates the volcanic rocks by about 8.8Ma. Biotite granite shows slightly older age than the main Tioman diorite by about 1.5 Ma. The geochemistry of the igneous rocks from southern Tioman Island shows that they have a high-calc alkaline affinity which suggests that they are related to arc magmatism.

Keywords: Tioman Island, hornblende diorite, biotite granite, rhyolite, dacite, arc magmatism, Late Cretaceous