Download NATIONAL GEOSCIENCE CONFERENCE 2014

NATIONAL GEOSCIENCE CONFERENCE 2014
TERENGGANU MAINLAND FIELD EXCURSION
Rock Diversity
A great diversity of rock types characterize the geology of Terengganu. These range
from basic to acidic igneous rocks, low to high grade metamorphic rocks as well as
sedimentary rocks of various origin and composition. Study of the distribution and
relationships of these various types of rocks allow us to unravel their geological history
such as their paleo-depositional environment and tectonic setting, both closely
associated with the broader geological and tectonic history of Peninsular Malaysia,
Borneo and the adjacent Southeast Asian region.
Fossil Diversity
Terengganu’s sedimentary rocks yield rich and diverse fossil assemblages, preserved
within strata of different ages from Carboniferous (ca. 340 million years ago) to recent
times. The bulk of Malaysian fossils are shells of marine invertebrates, ranging from
shallow to deep marine faunas. Fossil floras are also found. The distribution of the
different fossil groups is strongly controlled by the paleo-depositional environment and
paleo-tectonic setting of fossil-bearing strata, which in turn closely related to the tectonic
evolution of the country. Malaysian fossils are exhibited in some local museums and
rock galleries.
Stop #1. Brachiopods of Bukit Buchu, Terengganu
Sedimentary rocks in Terengganu, formed from marine sediments deposited in a
shallow sea in early Carboniferous times, are often very rich in both fossil fauna and
flora. At Bukit Buchu (Fig. 1), a rich fossil assemblage of brachiopods, trilobites,
cephalopods, bivalves, byrozoas, crinoids, echinoids and plant fragments are all well
preserved within vertically bedded light grey shale and light brown sandstone (Photo 1).
Cross bedding and ripple mark are also very well preserved in the sandstone. The
fauna discovered at Bukit Buchu are listed in Table 1 and some of the fossils are
illustrated in Plate 1.
Fig 1. Bukit Buchu (white triangle) at Batu Rakit.
Table 1. The fauna discovered at Bukit Buchu
Che Aziz Ali
& Kamal Roslan Mohamed (2001)
Bivalve
Edmondia sp.
Brachiopod
Chonetessarcinulatus
Chonetusplebejus
Cancrinellasp.
Brachithyrinastrangwasi
Echinoconchus ?
huaipotensis
Echinoconchussp.
Dictyoclostinaesp.
Bryozoans
Fenestellaangustata
Fenestella cf. Polyporata
Fenestellatenax
Crinoids
Potereocinussp.
Trilobite
Phillipsialaticaudata
Paladin ophistops
Photo 1: Bukit Buchu outcrop at Taman Atikah, Batu Rakit.
Plate 1. Brachiopods of Bukit Buchu.
Stop #2. Cathaysian Fossil Floras of Paya Peda, Besut
The geology of the Paya Peda (Fig. 2) area is made up of metamorphic rocks that
consist of quartzite, slate, metaconglomerate, and carbonaceous shale which belong to
Telemong and Keruak beds (Carboniferous-Permian??). These plant fossil-bearing
outcrops were exposed during excavation for the construction of roads (Photo 2). They
are found in slightly metamorphosed thick black shale (slate) and are believed to be
among the oldest plant fossils in Malaysia. These plant remains are believed to be Early
Carboniferous to Late Permian in age and related to pantropical Cathaysian and/ or
Laurasion floras. They include genus of Pecopteris sp., Tinggia sp., Lepidodendron sp.,
Lepidostrobos (reproductive part), Stigmaria (rhizome)., Cordaites sp., Artisia
horizontalis (Cordiates stem), Sigillaria sp., Sphenophyllum sp., and Neurotepris sp.
They are interpreted to represent deposition of continental sediments in a swampy area
or along low-energy streams.
Bukit Puteri
Bukit Keluang
Paya Peda
Fig. 2: Location of Paya Peda, Bukit Puteri and Bukit Keluang at Besut, Terengganu
Photo 2: Thick bedded carbonaceous shale that contains remains of Cathaysian floral
fossils.
Pecopteris sp.
Tinggia sp.
Sphenophyllum sp.
Sphenophyllum sp
Lepidodrendron
spTinggia sp.
Stop #3. Unconsolidated Conglomerate of Bukit Putri, Besut
Bukit Putri is located in the northern Besut District, Terengganu. The 188m high Bukit
Putri consists of a very thick sequence of unconsolidated gravel. The clasts of various
rock types are mainly subrounded to rounded gravel to boulders with diameters in the 5
to 200 cm range and floating in a groundmass of sand and pebbles. Gravel to boulder
sized clasts are dominated by sandstone. Clast size generally increases from east to
west. There are various primary structures and distinct bedding strike 290 ̊ and dipping
30 ̊ towards SSW. The sediment is probably of late Cenozoic age. Bukit Putri is located
within the Terengganu fault zone and was probably raised to its current position as a
diaper by during the isostatic uplift of the Boundary Range Granitoid. Along the western
side of Bukit Putri, unconsolidated conglomerate is unconformably underlain by metashale and sandstone with exposures up to an elevation of ca. 25 m (Photo 4).
Photo 3: Unconsolidated conglomerate bed at Bukit Puteri.
Photo 4: Exposures of underlying bedrock on SW side of Bukit Putri.
Stop #4. Conglomerate of Bukit Keluang, Besut
Bukit Keluang, Bukit Kubus and Bukit Dendong form three isolated hills along the
coastline of northern Terengganu (Fig. 2). These hills are made up of various
sedimentary rocks such as conglomerate, sandstone, siltstone and red shale that
comprise the Bukit Keluang Formation (Photo 5). Conglomerate (Photo 6) is
predominant at Bukit Keluang exhibiting various sedimentary structures suggesting that
it was deposited in an ancient river (Fig. 3). Meanwhile, red shale at Bukit Bubus and
Bukit Dendong contains plant fossils. Together these outcrops represent the best
example of Middle to Late Permian (approximately 260 million years old) terrestrial
deposits in the country (Kamal Roslan Mohamed et al. 2000). This geoheritage site also
features a beautiful sandy beach and various coastal erosion features.
Photo 5: Panoramic view of Bukit Keluang, Besut
Photo 6. Bukit Keluang conlomerate.
Fig 3: Bukit Keluang and hypothetical cross section.
POST-CONFERENCE ITINERARY FIELD EXCURSION
Leader: En. Hamlee Ismail, Jabatan Mineral dan Geosains Malaysia
Date
15th Jun 2014
Time
08.30 am
10.30 am
11.30 am
13.30 pm
14.30 pm
15.15 pm
17.00 pm
18.00 pm
Locations
Depart from, Grand Continental Hotel and UMT
Fieldwork at Bukit Buchu
Depart from Bukit Buchu to Bamboo Restaurant,
Kg. Raja for lunch
Lunch and zuhor prayer for muslim
Depart from Kg. Raja to Paya Peda
Fieldwork at Paya Peda,
Depart from Paya Peda to Bukit Puteri and Bukit
Keluang
End of programme