GENERAL ONSHORE TO SHALLOW MARINE CORRELATION OF CENOZOIC DEPOSITS OF WESTERN PENINSULAR MALAYSIA WITH EMPHASIS TO LUMUT-LANGKAWI AREA

This paper tries to explain the correlation between onshore-offshore parts of West Coast of Malaysia, with emphasis on the Lumut - Penang area. Basically, the main types of data used in this study are seismic lines at the offshore part in which newly acquired seismic survey (2013 & 2014) were utilized and borehole data at the onshore parts. This paper takes into account the past sea-level curve and the evolution of the fluvial system at the onshore parts as they hold the key on where is the provenance of the sediments in Malacca Straits. The integration of data which are mainly seismic on the offshore parts and borehole data onshore parts were done to further validate the interpretation. The integration of both data on a GIS map was made possible by using various software such as Global Mapper, with Data Elevation Model (DEM) used to track the surface of the cross section. The interpretation of the seismic were done by using conventional seismic stratigraphy rules, while the borehole interpretation were done mostly by analysing previous studies done.
There are 5 main seismic units found in the offshore area of west coast Peninsular Malaysia. The units were categorized based on the depth of the unit itself with Unit 1 as the deepest sequence, followed by Unit 2, 3, 4 and Unit 5 which is the shallowest sequence identified. These seismic stratigraphic unit were then correlated with the formation found in previous borehole studies done at the onshore parts, in which 4 formation were being able to be correlated with the offshore parts. The correlation takes into account the type of lithology, age and environment of deposition of the formation, thus being able to suggest the age of deposition of the offshore parts. A Sequential Stratigraphic Cross Section Model were then constructed that explains the coastal prism from onshore to shallow marine parts of the studied area.