Holocene Sea-level Change and The Development of Perak Coastal Plain, Perak, West Malaysia

This paper focuses on the geomorphology,
sedimentology and stratigraphy of Perak coastal deltaicplain
in relation to Holocene sea level change. Based on
analysis of topographic maps and aerial photographs, Perak
River has undergone five stages of evolutions before its
current river course. The first course (I) runs in a westerly
direction near Kg Tg. Blanja. The second (II) and third (III)
course stream towards southerly direction. The forth (IV)
course branch from the recent river. The fifth flows along
Kg. Ulu Dudap towards southerly direction. The first course
develop may has been influenced by the Quaternary and
Holocene development of the coastal plain. The river shifting
towards southerly direction resulted in partial silting of the
estuary. The Perak River has been shifted several times and
finally followed the direction of the current river.
Shallow boreholes from seventeen (17) locations within the
area of Parit- Lumut- Bagan Datoh- Langkap in south of
Perak has been analyzed. These data show that the Perak
coastal plain sedimentary succession can be divided into
three major intervals. The oldest interval A (Simpang
Formation) was deposited within fluvial environment during
the Pleistocene age. The second interval B (Gula Formation)
was deposited within a marine environment possibly related
to a sea level transgression. The third interval C forms
terrestrially; it shows similar characteristics as to Beruas
Formation, marked by the occurrences of peat and gravel
sediments. It records a phase sea level drop.
Keywords: Geomorphology, sedimentology, stratigraphy,
transgression, regression.