Semanggol Formation Research Articles

984 Middle and Late Permian radiolarians from the Semanggol Formation, Northwest Peninsular Malaysia

984 Middle and Late Permian radiolarians from the Semanggol Formation, Northwest Peninsular Malaysia

Thrust in the Semanggol Formation, Kuala Ketil, Kedah

An excavation of a small hill, Bukit Kukus in the vicinity of Kuala Ketil town exposed the chert unit of the Semanggol Formation which comprises black mudstone, sandstone, tuffaceous sandstone, tuff, paraconglomerate, siliceous shale and chert. The chert contains radiolarians indicating late Early Permian to Middle Triassic of age. These rocks are generally thrusted northward. The thrust and the normal faults occupy the same orientation of fault planes. The dextral faults also occupy the same orientation as the Bok Bak fault which is of sinistral. As the result of transpressional deformation northward thrusts occupy fault planes which were formally the normal faults. The normal faults are the extensional faults resulting from the sinistral movement of the Bok Bak fault. The northward thrust is generated from the dextral movements along the northwest and west-northwestern faults, and is interpreted to be the youngest fault movement onshore. Abstrak— Tarahan Bukit Kukus berhampiran dengan pekan Kuala Ketil mendedahkan unit rijang Formasi Semanggol yang terdiri daripada batu lumpur hitam, batu pasir, batu pasir bertuf, tuf, parakonglomerat, syal bersilika dan rijang. Rijang mengandungi radiolarian yang berusia akhir Perm Awal hingga Trias Tengah. Batuan tersebut secara umum tersungkup ke utara. Sesar sungkup dan sesar normal mempunyai orientasi yang serupa. Sesar dekstral pula juga menunjukkan orientasi yang serupa dengan sesar Bok Bak iaitu sesar sinistral. Sungkupan ke utara berupa hasil daripada keadaan transpresi yang dialami oleh satah sesar yang sebelumnya ialah sesar normal. Sesar-sesar normal tersebut ialah sesar ekstensi hasil daripada pergerakan sinistral sesar Bok Bak. Sungkupan ke utara terjana oleh pergerakan dekstral sesar-sesar berjurus baratlaut dan barat-baratlaut, dan ini berupa pergerakan yang terakhir dapat dikesan.

Stratigraphy and sedimentology of the chert unit of the Semanggol Formation

Excavation of rocks in the Semanggol Formation exposed more rock succession, making it feasible to study in detail the stratigraphical distribution of the rocks, their age and relationship among the units in the formation. Five Permian and four Triassic radiolarian biozones were recognized. Discovery of Permo-Triassic radiolarian faunas indicates the chert unit is partly equivalent in age to the rhythmite and conglomerate units. The chert unit is divided into eight sedimentary facies, which were deposited in an open-deep marine environment under the influence of different transport mechanisms. It is evident that there were widespread volcanogenic sediments prior to the deposition of the chert in the Semanggol Formation. Abstrak: Pengorekan batuan di Formasi Semanggol telah mendedahkan lebih banyak jujukan batuan yang membolehkan kajian terperinci sebaran stratigrafi, usia, dan hubungan unit-unit dalam formasi ini. Lima biozon Perm dan empat biozon Trias radiolaria telah dikenal pasti. Penemuan radiolaria Perm dan Trias menunjukkan unit rijang ini sebahagiannya setara dengan unit berirama dan konglomerat. Unit rijang boleh dibahagikan kepada lapan fasies endapan yang diendapkan dalam sekitaran samudera laut dalam di bawah pengaruh mekanisme pengankutan yang berbeza. Bukti juga menunjukkan kewujudan endapan volkanogen yang meluas sebelum berlakunya pengendapan rijang Formasi Semanggol.

Some Deep Water Middle Triassic Foraminifera from the Semanggol Formation

Eight benthic foraminiferal taxa were retrieved from siliceous mudstone samples col\ected from the Semanggol Formation at Bukit Lada and Merbau Pulas. The foraminifera consist of Pseudonodosaria densa. Pseudonodosaria lata, Psuedonodosaria obconica, Pseudonodosaria simpsonensis, Prodentalina sp A, Prodentalina sp B, Cryptoseptida sp., and Protonodosaria spp. The assemblage indicates that the depositional environment was a deep marine basin above the calcite compensation depth. Abstrak: Lapan taksa foraminifera bentos telah didapatkan semula daripada sampel batu lumpur bersilika yang dikutip dari Formasi Semanggol yang tersingkap di Bukit Lada dan Merbau Pulas. Foraminifera terdiri daripada Pseudonodosaria densa, Pseudonodosaria lata, Psuedonodosaria obconica, Pseudonodosaria simpsonensis, Prodentalina sp A, Prodentalina sp. B., Cryptoseptida sp., dan Protonodosaria spp. Himpunan ini menunjukkan sekitaran pengendapannya merupakan sekitaran lembangan samudera dalam di atas kedalaman pampasan kalsit.

Permian Radiolarian Biostratigraphy of the Semanggol Formation, south Kedah, Peninsular Malaysia

Thirty-seven taxa of Permian radiolarians were retrieved from chert samples collected from an outcrop at a construction site approximately 4.5 kIn east of Kuala Ketil Town. The chert samples were collected from interbedded siliceous shale, chert and tuff facies and thinly bedded chert facies. Five radiolarian assemblage-zones were recognized i.e. Pseudoalbaillella scalprata In. rhombothoracata Zone, Follicucullus monacantha Zone, Follucucullus porrectus Zone, Neoalbaillella ornithoformis Zone and Neoalbaillella opima Zone. The radiolarian zones represent an age range from late Early Permian to Late Permian. Abstrak: Tiga puluh tujuh taksa radiolaria Perm telah diperolehi daripada sampel rijang yang dikutip dari satu singkapan tapak binaan yang terletak 4.5 kIn di timur pekan Kuala Ketil. Sampel rijang dikutip daripada fasies selanglapis syal bersilika, rijang dan tuff dan fasies rijang berpelapisan nipis. Lima zon himpunan radiolaria telah dikenali iaitu; Zon Pseudoalbaillella scalprata In. rhombothoracata, Zon Follicucullus monacanthus, Zon Follicucullus porrectus, Zon Neoalbaillella omithoformis dan Neoalbaillella optima. Zon radiolaria ini mewakili julat usia dari akhir Perm Awal hingga Perm Akhir.

Triassic Radiolarian Biostratigraphy of the Semanggol Formation, South Kedah, Peninsular Malaysia

Triassic Radiolarian Biostratigraphy of the Semanggol Formation, South Kedah, Peninsular Malaysia

Permo-Triassic radiolaria from the Semanggol formation, northwest Peninsular Malaysia

A total of 32 species of radiolaria were identified from 20 chert samples at eight localities of the Semanggol Formation in north and south Kedah. Three assemblages of Radiolaria were recognised representing the Early Permian Pseudoalbaillella scalprata m. rhombothoracata. Late Permian Albaillella levis, and Middle Triassic Triassocampe deweveri Assemblage-Zone. The Pseudoalbaillella scalprata m. rhombothoracata Assemblage-Zone is discovered from Bukit Kampung Yoi and Bukit Larek, north Kedah. The Albaillella levis Assemblage-Zone is recorded from Bukit Tok Bertanduk, north Kedah and Merbau Palas, south Kedah. The Triassocampe deweveri Assemblage-Zone is found from the Lanjut Malau area, north Kedah. The radiolarian assemblages indicate that the age of the chert sequence in the Semanggol Formation ranges from Early permian to Middle Triassic.

Permo-Triassic radiolaria from the Semanggol Formation, northwest Peninsular Malaysia

Permo-Triassic radiolaria from the Semanggol Formation, northwest Peninsular Malaysia

Permo-triassic Radiolaria from the Semanggol Formation, northwest Peninsular Malaysia

Permo-triassic Radiolaria from the Semanggol Formation, northwest Peninsular Malaysia

Implications of new biostratigraphic data for stratigraphic correlation of the Permian and Triassic in Peninsular Malaysia

Recent biostratigraphic work necessitates revision of the ages of several Permo-Triassic formations and units within Peninsular Malaysia. The Chuping Limestone in Perlis is now known to extend up to the Late Triassic. Cherts which have been assigned to the Semanggol Formation in Kedah have various ages ranging from Lower Permian to Upper Triassic. This extended age range for these cherts has implications for regional Permian palaeogeography and tectonics. Newly determined Permian ages of clasts in melange and Lower and Upper Permian ages of bedded cherts along the Raub-Bentong suture zone suggest a latest Permian or Triassic closure of the Palaeo-Tethys in this region. The presence of previously unknown tracts of Lower Triassic limestones in the Central Belt (Jerus Limestone) and subsurface Triassic limestones in the basement of the Malay basin, offshore Terengganu also have regional stratigraphic and tectonic implications. A correlation chart for sedimentary rock units in Peninsular Malaysia, incorporating the new biostratigraphic data is presented.

Late Palaeozoic radiolarians from the Bentong-Raub suture zone, and the Semanggol formation of Peninsular Malaysia—initial results

Cherts and tuffaceous siltstones from the Bentong-Raub suture zone, Peninsular Malaysia, have yielded radiolarians indicating Late Devonian (Famennian) and Early Carboniferous (Tournaisian, late? Tournaisian and Viséan) ages. Cerium anomalies from these Devonian and Carboniferous cherts indicate deposition in an open ocean. This ocean is interpreted to be the Palaeo-Tethys ocean which existed between Sibumasu and East Malaya during at least the Devonian and Early Carboniferous. Radiolarians extracted from siliceous sediments of the Semanggol Formation of NW Peninsular Malaysia have indicated both Early Permian and Late Permian (Guadalupian) ages. This extends the age of the Semanggol Formation down to the Early Permian and confirms the presence of a deep-marine basin in what is now NW Peninsular Malaysia during the Permian.

Stratigraphic and tectonic implications of Triassic conodonts from northwest Peninsular Malaysia

AbstractThe Chuping Limestone of northwest Peninsular Malaysia, until recently considered entirely of Permian age, has yielded late Triassic (early Norian) conodonts. TheLimestone thus spans the time interval late Early Permian–Late Triassic and is in part equivalent to the Kodiang Limestone (Late Permian–Late Triassic) in Kedah andsimilar limestone sequences in south Thailand and north Sumatra. Early Late Triassic (Carnian) conodonts are also reported from pelagic limestones associated with bedded chertsof the Chert Member of the Semanggol Formation in Kedah. The Chert Member, previously considered of Middle Triassic age, is re-interpreted to represent Early, Middle and early Late Triassic deposition. The Triassic sedimentary rocks of the Malay Peninsula represent three distinct sedimentary regions: a stable shallow marine carbonate complex (ChupingLimestone, Kodiang Limestone), which forms part of an elongate carbonate platform on theSibumasu block; a deep water pelagic/turbidite basinal sequence (Semanggol Formation) which accumulated in either a foredeep basin or an intracratonic pull-apart basin related to strike-slip faulting; and a volcanic-sourced volcaniclastic basinal sequence on the East Malaya block (Semantan Formation and equivalents) which accumulated in either a forearc/intra-arc setting, or in a post-orogenic rift basin.

Triassic conodont biostratigraphy in the Malay Peninsula

Conodonts representative of the Lower, Middle and Upper Triassic are now known in the Malay Peninsula and all the Triassic Stages except the Rhaetian are represented. The best known sequence of Triassic conodonts occurs in the Kodiang Limestone ofKedah but there are still significant gaps in the known conodont succession. In particular, Griesbachian and Dienerian conodonts are poorly known and conodonts representative of the Upper Spathian, Lower Ladinian, Middle and Upper Norian and Rhaetian are unknown. New data from the Kodiang Limestone ofBukit Mulong and Bukit Kepelu help to fill some of these gaps in the Carnian and Norian conodont succession. The Chuping Limestone of Per lis has also recently yielded some Lower Norian conodonts which implies a correlation with the Kodiang Limestone to the south. Other recent discoveries include early Late Triassic (Lower Carnian) conodonts from the Chert Member of the Semanggol Formation, Kedah, Early Triassic (Spathian) conodonts from north-west Pahang and Early Triassic (upper Dienerian) and Middle Triassic (upper Anisian) conodonts from the Jerus Limestone, Cheroh, west Pahang.