Warta Geologi, Vol. 47, No. 1, April 2021, pp. 29 - 48


Warta Geologi, Vol. 47, No. 1, April 2021, pp. 29 - 48

Reconnaissance of Kenny Hill Formation outcrops in the Rawang area, northern Selangor, Malaysia

Allan Filipov1,*, John Jong2, Mazlan Madon3

1 GFSI LLC, Kuala Lumpur, Malaysia
2 JX Nippon and Gas Exploration (Malaysia) Limited, KL, Malaysia
3 Department of Geology, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
* Corresponding author email address: allan.filipov@yahoo.com

Abstract: New outcrops of Paleozoic meta-sediments northwest of Kuala Lumpur expose the deformational effects of the Late Paleozoic-Mesozoic collisions between various Gondwana-derived continental fragments as they amalgamated to form the core of SE Asia. Over a duration of 6 months, beginning in August 2020, we conducted field trips within northern Selangor to new laterally extensive outcrops for field observations, structural mapping and to measure and log the stratigraphic section. This paper focuses on Upper Paleozoic Kenny Hill Formation outcrops in northern Selangor. The most studied is the heavily weathered Jalan Rawang-Bestari Jaya (JRBJ) outcrop, which is characterised by a steeply dipping (southwest), upward-coarsening succession of sandstones and shales interpreted as a system of ephemeral fluvial channels possibly related to Gondwana glaciation. Concretions within bedding planes and fractures were possibly formed around organic material. Less than 4 km to the east, the Scientex development has excavated fresher outcrops of the same rocks dipping to the NE. Metamorphic lineation is not present in either outcrop location. In addition, a monocline is exposed at outcrop location number 3 nearby. Finally, at Bukit Botak, 14 km to the southwest, a system of westward verging thrust faults, back thrusts and normal faults can be viewed and an angular unconformity or decollement marks the contact between the Upper and Lower Paleozoic. These laterally extensive outcrops are rare and are quickly subject to intense tropical weathering, the encroachment of jungle vegetation and urban development. Historic mapping and prior stratigraphic, structural, and petrographic studies have been conducted in the area, but these relied on poor exposures. As suburban development escalates in the area, we hope that new outcrops, featuring multi-dimensional views of these formations, such as the four described in this paper, will complement the earlier work.

Key words: Upper Paleozoic, Kenny Hill Formation, Rawang

DOI : https://doi.org/10.7186/wg471202104