Evidences for syn-depositional tectonism in the Tertiary boulder beds of Batu Arang

702001-100843-649-B
Author : Mustaffa Kamal Shuib and Abdul Hadi Abd. Rahman
Publication : Bulletin of the Geological Society of Malaysia
Page : 187-196
Volume Number : 42
DOI : https://doi.org/10.7186/bgsm42199816

Bulletin of the Geological Society of Malaysia, Volume 42, Dec. 1998, pp. 187 - 196

 

Evidences for syn-depositionai tectonism in the Tertiary boulder beds of Batu Arang

MUSTAFFA KAMAL SHUIB AND ABDUL HADI ABD. RAHMAN

Department of Geology, University Malaya, 50603 Kuala Lumpur

 

Abstract: Based on a preliminary sedimentological and deformational study, the Tertiary Boulder Beds of Batu Arang can be divided into two distinct sequences - the Red and the Gray Conglomeratic units, separated by an angular unconformity. The Red Conglomeratic Unit was deposited sub-areally, whilst the Gray Unit was deposited in a reducing, subaqueous environment.

Numerous evidences for the interplay between tectonism and sedimentation are found within the Boulder Beds. These includes:

1. the immaturity of the sediments, compositionally and texturally;

2. cyclicity of the fining-upward sequences;

3. the occurrence of the intrabasinal angular unconformity between the Red and the Gray Units;

4. the presence of syn-depositional structures.

These evidences suggest that the Boulder beds were deposited in a fault-controlled basin. The presence of post-depositional strike-slip faults suggest that tectonism out-lasted sedimentation and together with the proximity of the basin to the Kuala Lumpur Fault zone, may suggest that the basin may have developed along a strike-slip fault.

https://doi.org/10.7186/bgsm42199816