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Volcaniclastic rocks in East Johor Basin are found in a relatively great abundance comprising Sedili and Pengerang Formations excluding the metamorphics, siliciclastics, and granites. Since the volcaniclastic rocks are found in a different formation, this study aims to find out the characteristics of each rock. Geology, petrography, and geochemical analyses were elaborated to reveal the petrogenesis and depositional environment in the studied area on the basis of fieldwork data and 24 samples collected from outcrops. The Sedili and Pengerang Formations are dominated by acidic rocks of rhyolite, rhyodacite, ignimbrite, and lava classifiied into calc-alkaline magma series which indicates a subduction-related product. Moreover, those acidic rocks are grouped into active continental margin. Eventhough volcanic rocks in Sedili and Pengerang Formations exhibit similar characteristics, they are different in several major contents. Therefore, it is inferred that both Sedili and Pengerang Formations were deposited in different phase. Coincidentally, depositional environment of both formations is also distinct. Sedili Formation were deposited in the subaerial to shallow marine, meanwhile, Pengerang Formation is interpreted to be deposited in deeper depositional setting.

A new Middle Permian locality in northern Johore, Peninsular Malaysia, yields a smallsized, but compositionally unique, brachiopod fauna consisting of eight species: Pseudoleptodus sp., Caricula cf. salebrosa Grant, Neochonetes (Nongtaia) aff. arabicus (Hudson & Sudbury), Karavankina sp., Transennatia cf. insculpta (Grant), Hustedia sp., Orthothetina sp., and martiniid indet. The first four genera are new records for Malaysia; in particular, the rare taxa Pseudoleptodus and Caricula characterize the fauna. The brachiopods occur together with the ammonoid Agathiceras sp., the nautiloid Foordiceras? sp., bivalves, and crinoid stems. The locality belongs to the East Malaya terrane of the Cathaysian biotic region, but some affinities to species of the Sibumasu province are recognized. The Malaysian forms of Pseudoleptodus, Caricula and Transennatia are similar to those of the Ratburi Limestone (southern Thailand). A Roadian-early Wordian age is interpreted for the Johore fauna. The similarity of brachiopods reported here with those from the Ratburi Limestone suggests that there was species interchange or one-way migration between shallow waters of East Malaya and Sibumasu across the main Palaeo-Tethys. The Tethyan seaway between the two terranes must have been narrower than previously interpreted by some authors to allow such faunal traffic during the Roadian-Wordian time period. Keywords: Permian, Malaysia, brachiopods, palaeobiogeography.

Several greywacke sandstones considered as Paleozoic rocks are found in three different formations, i.e. the Dohol, Linggiu, and Tanjung Leman Formations within the Palaeozoic East Johor Basin. The compositions of twenty-nine sandstone samples were identified using petrographical and geochemical methods to determine the provenance of sandstones as well as the tectonic setting of pre-and syn-sedimentation. Seven samples of them were examined using point counting method to obtain the mineralogical compositions. This petrographical point counting was done by plotting composition percentages to QFL and QmFLt triangular diagrams, The results showed a magmatic arc for Dohol Formation, a change from a magmatic to a recycled orogen for Linggiu Formation, and a recycled orogen for Tanjung Leman Formation. The recycled orogen tectonic setting of Linggiu and Tanjung Leman may have come from the underlying metamorphic and sedimentary rocks of Mersing and Murau Formations. Meanwhile, twenty-two samples were examined using a geochemical method by utilizing the ratio of K2O/Na2O and SiO2. The samples suggest a tectonic setting from both passive continental margin (PM) and active continental margin (ACM). Based on these findings, it is interpreted that the sedimentary rocks in East Johor were deposited in a subduction-related basin, such as fore-arc, magmatic arc, and back-arc. [ABSTRACT FROM AUTHOR]

The Lower Setul Limestone in the Langkawi Islands of Peninsular Malaysia is well known for its continuous succession for most of the Ordovician Period. It is part of an extensive carbonate platform in the West Malaya (=Sibumasu) Block that is considered to have been in low-latitude, northern Gondwana during the early Palaeozoic. Highly endemic cephalopods belonging to the two orders Orthocerida and Pseudorthocerida occur in the late Floian–early Sandbian (late Early–early Late Ordovician) sections of this limestone. Based on some 170 shells collected, 10 species out of six genera were identified: the four orthocerids, Malayorthoceras gracilentum gen. et sp. nov., Tofangoceras kedahense sp. nov., Tofangoceras staiti sp. nov. and Tofangoceras rayense sp. nov.; and the six pseudorthocerids, Andamanoceras densiseptum gen. et sp. nov., Langgunites mucronulatus gen. et sp. nov., Shanthaiceras amplum gen. et sp. nov., Sibumasuoceras langkawiense (Kobayashi, 1959), Sibumasuoceras kilimense sp. nov. and Sibumasuoceras scrivenori sp. nov. Tofangoceras, a typical Darriwilian–Sandbian element of the North China Platform, was found also to be abundant and diverse in the coeval strata of Malaysia. All of the Langkawi pseudorthocerids belong to Greenlandoceratidae, an ill-defined familial group that is here reviewed and emended comprehensively. The Greenlandoceratidae are the oldest Pseudorthocerida and occur predominantly in both South-East Asia and North China. Langgunites mucronulatus from the Floian is the earliest species of Pseudorthocerida and possesses some primitive features of the order. The poorly understood origin of Pseudorthocerida is revisited. Pseudorthocerida is traditionally believed to have split off from Orthocerida; however, we suggest an alternative view that it derived from a stock of Protactinoceratidae (order Plectoronocerida). [ABSTRACT FROM AUTHOR]

The search for the critical Permian-Triassic Boundary (PTB) in Malaysia focuses on limestone hills in the Lipis district since the 1990s. The recent paleontological findings at Gua Panjang hill in Merapoh, Pahang state, has constrained the presence of PTB to be between 6.50 m to 9.00 m from the base of the logged section at the eastern cliff. Late Permian foraminifera such as Colaniella sp., Ichtyofrondina sp., and Palaeotextularia sp. were observed 6.50 m from the base of the logged section, where the microfacies is characterized as bioclastic grainstone deposited within a shallow open shelf environment during Late Permian. Located 2.50 m above the Late Permian horizon is a highly dolomitized horizon with the presence of earliest Triassic conodonts such as Hindeodus parvus and Isarcicella staeschi. Between the height of 6.50 m and 9.00 m, analyses on δ13C and δ18O of the whole rock composition have shown slight decrease in both isotopes to 1.18‰ (VPDB) and 18.23‰ (SMOW), respectively. However, a negative carbon isotope excursion, which is the signature in most PTB sections worldwide, was not observed in the Gua Panjang limestone section potentially due to the large-spaced sampling. Therefore, a high precision research on the 10.00 m logged section at the eastern cliff of the Gua Panjang hill is crucial to identify the precise position of the first PTB in Malaysia. [ABSTRACT FROM AUTHOR]

Mesozoic strata in the East Malaya Terrane of Peninsular Malaysia record a long but poorly constrained history of basin evolution. In this study, we report LA‐ICP‐MS U–Pb geochronology analyses of detrital zircons in the continental Mesozoic sequences from the Bertangga and Gerek formations of Peninsular Malaysia, with the aim to constrain the depositional ages and provenances of the continental Mesozoic strata as well as the Mesozoic tectonic evolution of the East Malaya Terrane. The Bertangga Formation yields populations of U–Pb zircon ages of Jurassic (139 to 194 Ma), Permo−Triassic (226 to 274 Ma), Ordovician−Devonian (372 to 459 Ma), Neoproterozoic (631 to 876 Ma), and Mesoproterozoic−Palaeoproterozoic (1,448 to 2,629 Ma). In contrast, the Gerek Formation yields significant Carboniferous grains, but with an approximate zircon age range relative to the Bertangga Formation. The new data indicate a maximum Late Jurassic depositional age for the previously undated Bertangga Formation. Similarly, young zircon grain ages in the Gerek Formation also indicate a maximum Late Jurassic depositional age. Collectively, these results on detrital zircons correlate well with a regional tectonic uplift and erosion to a tectonic stability of the East Malaya Terrane basin during the Mesozoic. [ABSTRACT FROM AUTHOR]

The Archaeological Heritage of Lenggong Valley has a high potential to be developed as geotourism and archaeotourism destination. The diversity in geology and geomorphology of the area represent scientific, cultural, aesthetic as well as recreational values and together define the geodiversity of this area. This paper proposes a basic geotouristic itinerary connects a series of impressive geosites distributed in Lenggong Valley which can explain the high potential interest of the area in geotourism and archaeotourism terms. In order to enhance and highlight their importance to the geological and archaeological heritage, the location, accessibility, important geological-scientific features or historical-cultural interest, related activities as well as available facilities was described. The motivation for establishing this itinerary mostly resides in the great scientific and cultural interest of the geosites that will hopefully facilitate their conservation and the development of geo-archaeotourism to continuously attract a large number of visitors year by year. The itinerary can be used for teaching purposes at different educational levels, geotourists and geopark guides and for university courses. In addition, non-geologists may follow the itinerary guided by expert volunteers to discover the geological and archaeological heritage of the area. [ABSTRACT FROM AUTHOR]

Nine species of late Pridoli (latest Silurian) orthocerid cephalopods are described from the Upper Setul Limestone of Pulau Langgun, Langkawi Islands, Malaysia. These are the orthoceratidsMichelinoceras(Michelinoceras) cf.michelini(Barrande, 1866),Michelinoceras? sp.,Kopaninoceras setulensesp. nov.,Mimogeisonoceras?langgunensesp. nov.,Kionoceras? sp. andOrthocyclocerassp.; the arionoceratidsArionoceras mahsurisp. nov. andCaliceras mempelamensesp. nov.; and the geisonoceratidMurchisoniceras? sp. This is the first detailed record with taxonomic descriptions of Silurian cephalopods from Southeast Asia. The assemblage belongs to the newly definedKopaninocerasFauna that is interpreted to have been widely distributed along the northern (African to Asian) margin of Gondwana and around the Prototethys Ocean during the late Silurian. TheKopaninocerasFauna includes a local assemblage from the Kurosegawa Belt of south-west Japan, which possibly represents its northernmost occurrence. The distribution of theKopaninocerasFauna implies that the cephalopod faunas of Kazakhstan and adjacent areas in Central Asia have closer affinities with peri-Gondwanan faunas than with Baltica or Siberia, corroborating conclusions drawn by earlier researchers based on the benthic faunas. http://zoobank.org/urn:lsid:zoobank.org:pub:DDE20872-C142-4B78-B5F2-2E604C3C8689 [ABSTRACT FROM AUTHOR]

The close association between the Gua Musang formation, Telong formation, Aring Formation, and Nilam marble reflect the lateral facies changes among these formations. Poorly delineated boundaries between each formation calls for a reassessment on the genetic and stratigraphic correlation of these formations. The newly proposed Gua Musang Group is defined as argillite-carbonate-volcanic deposited within the same Gua Musang platform during Permo-Triassic period, which includes all four formations under study. High resolution stratigraphy is needed for each formation for better stratigraphic correlation between the various lithostratigraphic units of the Gua Musang Group and other chronologically related rock formations in the region. The new division of formations within this Group is proposed based on lithologies and stratigraphic correlation that could provide better understanding on the geology of northern section of Central Belt of Peninsular Malaysia. [ABSTRACT FROM AUTHOR]

A total of seven quite well-preserved radiolarian species of Pseudoalbaillella genus were found in chert rock, situated at a road cut slope between the Gua Musang town and Cameron Highland, south west of Kelantan. These species are Permian age and was determined by the external skeleton morphological comparative study. Based on radiolarian composition and the association of Pseudoalbaillella with Hegleria mammilla (Sheng & Wang), the rock sequence can be assigned to Pseudoalbaillella globosa Assemblage Zone which represents Early Middle Permian (Roadian). The term and morphological characteristics of these radiolarian are described systematically in Malay Language. [ABSTRACT FROM AUTHOR]

In order to understand the aesthetic value of geological landscape, a study was conducted at Dataran Lang viewing point, Kuah, Langkawi based on horizontal viewpoint landscape mapping and public perception survey method. From the mapping exercise several types of landforms and landscapes have been identified and were associated to their various geological formations. In addition to these natural landforms, several man-made landscapes were also identified. Data obtained were transformed into a simple schematic sketch to relate the landscapes with the rock types. Using this sketch as a guide, a public perception survey was carried out to find out the visitors' understanding and perception on landscape of scenic beauty and their relationship with geology. The survey has shown that most visitors agreed that landscapes seen from Dataran Lang have scenic appeal or aesthetic value. The sketch was useful to help them relating the different landscapes with different geological or scientific information. The schematic geological sketch interpretation is an important tool for enhancing public understanding on geological landscape, geoheritage, and geotourism as well as a tool in future development planning related to the aesthetic geological landscapes. [ABSTRACT FROM AUTHOR]

Early Permian(Sakmarian) radiolarian were discovered from chert beds from a new outcrop at Pos Blau, Ulu Kelantan. Seventeen chert samples were collected, thirteen of which yielded fairly well preserved radiolarian fossils. A total of twenty eight species were identified belonging to thirteen genera from seven families. Two radiolarian assemblage zones were identified i.e. Pseudoalbaillella lomentaria Assemblage Zone indicative of Early Sakmarian age and Pseudoalbaillella scalprata m. rhombothoracata Assemblage Zone represents Late Sakmarian age. The radiolarian cherts are interbedded with shale and is interpreted as a chert-shale association or continental margin chert association. This association shows that the radiolarian chert was deposited in an environment close to continental margin. [ABSTRACT FROM AUTHOR]

Some 13 species of Middle Triassic ammonoid fossils were discovered from two outcrops of sedimentary rocks belonging to the Telong Formation. The outcrops are located within the Felda Aring 5, along the road connecting Gua Musang Town and Kuala Berang. These two localities contained two ammonoid assemblages that are correlatable with the Standard Ammonoid Zone of the Tethyan region. Locality QZ480 contains four ammonoid species i.e. Balatonites cf. B. balatonicus, Danubites kansa, Kellnerites samneuensis, Hollandites sp. and Acrocordiceras sp., while locality QZ467 contains eight species i.e. Frankites regoledanus, Frankites apertus, Celtites epolensis, Clionitites sp., Protrachyceras costulatum, Anolcites sp., Joannites sp. and Megaphyllites jarbas. Biostratigraphically, ammonoid assemblage of locality QZ480 characterize the middle Anisian Balatonicus Subzone of Balatonites Zone while those of locality QZ467 characterize the late Ladinian Regoledanus Subzone of Protrachyceras Zone. Based on correlation, the results support the idea that the study area which can be correlated to the Triassic Lampang-Phrae Basin located on the Sukhorthai Terrain of Shan-Thai Block, belonging to the Cathaysian domain. The ammonoid assemblages pose a high scientific heritage value, particularly in their role as good age indicators for the Triassic. [ABSTRACT FROM AUTHOR]