UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

A new upper Paleogene to Neogene stratigraphy for Sarawak and Labuan in northwestern Borneo: Paleogeography of the eastern Sundaland margin

Hennig-Breitfeld, J; Breitfeld, HT; Hall, R; BouDagher-Fadel, M; Thirlwall, M; (2019) A new upper Paleogene to Neogene stratigraphy for Sarawak and Labuan in northwestern Borneo: Paleogeography of the eastern Sundaland margin. Earth-Science Reviews , 190 pp. 1-32. 10.1016/j.earscirev.2018.12.006. Green open access

[thumbnail of manuscript_Hennig-Breitfeld etal_NW Borneo stratigraphy.pdf]
Preview
Text
manuscript_Hennig-Breitfeld etal_NW Borneo stratigraphy.pdf - Accepted Version

Download (31MB) | Preview

Abstract

The Miri Zone in Sarawak contains thick Paleogene to Neogene sedimentary successions that extend offshore into the Sarawak Basin (Balingian and Central Luconia Provinces) and Sabah Basin. Exploration offshore has shown the Sarawak Basin in the South China Sea contains major hydrocarbon reservoirs. The sediments on land are age equivalents of the offshore successions and can be used to provide insights into their sedimentological and stratigraphic relations. However, because the rocks are found in mountainous regions covered by dense rainforest much of the stratigraphy in the Miri Zone is poorly known, as are timings and causes of major unconformities in the region that are essential for understanding the tectonic history, basin development, and sedimentary pathways. In this study we integrate fieldwork, U–Pb zircon dating, biostratigraphy, and light and heavy mineral analyses to present a revised stratigraphy for the region as well as paleogeographic maps, including major paleo-river systems for the main sedimentary basins. Rocks studied include parts of the Cretaceous to Eocene deep marine Rajang Group, fluvial to marginal marine sediments of the Oligocene to Early Miocene Tatau, Buan, Nyalau and Setap Shale Formations, and the Miocene sediments which are assigned to the Balingian, Begrih and Liang Formations in the Mukah-Balingian province, and the Belait Formation on Labuan. There is still much debate about the timings or even existence of some important unconformities offshore, such as the Middle Miocene Unconformity (MMU) and Deep Regional Unconformity (DRU). We propose to avoid the ambiguous time-based terminology that has been used for different events by different authors. Instead, our results from the on-land stratigraphy show two main unconformities in northern Sarawak; one at c. 37 Ma (Rajang Unconformity), marking the change from deep marine to fluvial – marginal marine sedimentation, and another one at c. 17 Ma (Nyalau Unconformity) which is related to widespread uplift in Borneo and changing river systems.

Type: Article
Title: A new upper Paleogene to Neogene stratigraphy for Sarawak and Labuan in northwestern Borneo: Paleogeography of the eastern Sundaland margin
Open access status: An open access version is available from UCL Discovery
DOI: 10.1016/j.earscirev.2018.12.006
Publisher version: https://doi.org/10.1016/j.earscirev.2018.12.006
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
Keywords: Borneo; Miri Zone; Balingian-Luconia; Rajang Unconformity; paleogeography; provenance; U-Pb zircon geochronology
UCL classification: UCL
URI: https://discovery.ucl.ac.uk/id/eprint/10066717
Downloads since deposit
Loading...
178Downloads
Download activity - last month
Loading...
Download activity - last 12 months
Loading...
Downloads by country - last 12 months
Loading...

Archive Staff Only

View Item View Item