STRATIGRAPHY AND PALAEOICHNOLOGY OF THE “BLACK SHALE” FACIES (CHERT UNIT) OF THE SEMANGGOL FORMATION AT BUKIT MERAH (N PERAK)

• Main Author: BINTI DRAHMAN, FARAHANA AZWA
• Format: Final Year Project
• Language: English
• Published: Universiti Teknologi PETRONAS 2015
• Subjects: G Geography (General)
• Online Access: http://utpedia.utp.edu.my/18181/1/Dissertation_Hardbound_Edited.pdf; http://utpedia.utp.edu.my/18181/

The wide exposed area of Bukit Putus, one of Semanggol abandoned quarry in Bukit Merah has allowed to start a detailed study of the chert unit of the Semanggol Formation. Chert unit in particular were deposited in a basin of deep ocean environment under the influence of different regimes of transportation, Basir Jasin & Zaiton Harun (2007). Till date, no integrated stratigraphy and palaeoichnological has yet been presented particularly in this area although the siliciclastic succession of Bukit Merah has been described by Hutchison & Tan (2009), as deep-water deposits across the Semanggol Basin. The analysis conducted aim to reconstruct its paleoenvironment evolution. Fieldwork and few data collection has been done in order to produce a geological map of the study area as well as the stratigraphic logging. The samples collected have been studied and examined by means of thin sections, Total Organic Content (TOC), Scanning Electron Microscope (SEM) – EDX, and photography and image enhancement. Sedimentary facies and facies association description will be done on the outcrop of the ‘black shale facies’ of the chert unit. As a result, trace and body fossil data are in agreement with the sedimentological ones; basin evolved from – mid and distal continental shelf situations to shallower sublittoral conditions. The general sedimentary evolution is compatible with the dynamics of a deltaic apparatus prograding seaward (prodelta evolving into lower delta front). The "black shale" facies are reflecting true anoxic conditions during deposition only in a few cases (i.e., where rocks lack completely benthic body and trace fossils). In most of the black shale intervals anoxia was reached after burial, as they show a moderate to high palaeontological contents of benthic origin. Bivalves of Claraia (suspected) sp, a Permo-Triassic bivalve which belongs to Aviculopectinidae family and also brachiopod interpreted as from Lingulida family has also been discovered at the outcrop of Bukit Putus quarry. In short, the result from integration of stratigraphy and paleoichnology has supported the hypothesis of this study.