A Review of the Bentong-Raub Suture vis-à-vis New Insight of the Tectonic Evolution of Malay Peninsula,South East Asia

Genesis of the so-called Bentong-Raub Suture of Malay Peninsula does not fit to the model of subduction-related collision.It has evolved from transpression tectonics resulting closure and exhumation of the inland basin which underwent extensive back-arc extension during Triassic.Crust having similar thickness（average-35 km） below entire Malay Peninsula nagate collision of two separate continental blocks rather supports single continental block that collided with South China continental block during Permo-Triassic.Westward subduction of intervening sea（Proto South China Sea） below Malay Peninsula resulted in widespread I- and S-Type granitization and volcanism in the back-arc basins during Triassic.Extensive occurrence of Permo-Triassic Pahang volcanics of predominantly rhyolitic tuff suggest its derivation from back-arc extension.Back-arc extension,basin development and sedimentation of the central belt of the peninsula continued until Cretaceous.A-Type granite of metaluminous to peraluminous character indicates their emplacement in an intraplate tectonic setting.Malay Peninsula suffered an anticlockwise rotation due to the rifting of Luconia-Dangerous Grounds from the east Asia in the Late Cretaceous-Early Tertiary.Extensive ductile and brittle deformation including crustal segmentation,pull-apart fracturing and faulting occurred during the closure and exhumation of the basins developed in the peninsula during Late Cretaceous-Early Tertiary.Crustal shortening in the central belt of the peninsula has been accomodated through strike-slip displacement,shearing and uplift.

Chemical weathering in Malay Peninsula and North Borneo:Clay mineralogy and element geochemistry of river surface sediments

Weathering products of silicate rocks are particularly useful for evaluating the continental chemical weathering on the Earth's surface and its mechanism.Clay mineralogy and major-element geochemistry of surface sediment samples collected in major rivers of Malay Peninsula and North Borneo in the tropical Southeast Asian region are used to study the present chemical weathering process and its controlling factors of tropical regions.The results indicate that the clay mineral assemblage in Malay Peninsula consists dominantly of kaolinite(average 80%) and minor illite(average 17%),almost without chlorite and smectite,whereas in North Borneo it consists mainly of illite and chlorite,with minor amounts of kaolinite(average 14%) and no smectite.Total contents of illite and chlorite in both Northwest and Northeast Borneo are 84% and 87%,respectively.Major-element geochemical results of both bulk and clay-fraction sediments show intensive chemical weathering degree for both areas.Relatively,the chemical weathering degree is gradually strengthened from Northeast Borneo,Northwest Borneo,to Malay Peninsula,and it is extremely intensive in Malay Peninsula.Our results indicate that,in the tropical Southeast Asian region exampled by Malay Peninsula and Borneo,climatic condition of tropical warm temperature and East Asian monsoon rainfall is the first-order controlling factor on the chemical weathering,resulting in intensive chemical weathering throughout tropical areas,and tectonic activity and lithology of parent rocks are subordinate factors,which still have an important impact on the weathering products,forming completely different clay mineral assemblages between Malay Peninsula and Borneo.

Late Eocene–early Miocene provenance evolution of the Crocker Fan in the southern South China Sea

There are many large-scale Cenozoic sedimentary basins with plentiful river deltas,deep-water fans and carbonate platforms in the southern South China Sea.The Crocker Fan was deposited as a typical submarine fan during the late Eocene–early Miocene,and stretches extensively across the entire Sarawak–Sabah of the northern Borneo area.However,systematic analyses are still lacking regarding its sediment composition and potential source suppliers.No consensus has been reached yet on the provenance evolution and sedimentary infilling processes,which seriously impeded the oil-and-gas exploration undertakings.By combining with sedimentaryfacies identification,heavy mineral assemblages,elemental geochemistry and detrital zircon U-Pb dating,this paper aims to generalize an integrated analysis on the potential provenance terranes and restore source-to-sink pathways of the Crocker Fan.In general,the Crocker Fan was initially formed over the Cretaceous–lower/middle Eocene Rajang Group by an angular Rajang unconformity.The continual southward subduction of the protoSouth China Sea resulted in magmatic activities and subsequent regional deformation and thrusting along the Lupar Line in the northern Borneo.The lowermost Crocker sequence is featured by a thick conglomerate layer sourced from in-situ or adjacent paleo-uplifts.From the late Eocene to the early Miocene,the Crocker Fan was constantly delivered with voluminous detritus from the Malay Peninsula of the western Sundaland.The Zengmu Basin was widely deposited with delta plain and neritic facies sediments,while the Brunei-Sabah Basin,to the farther east,was ubiquitously characterized by turbiditic sequences.The Crocker Fan successions are overall thick layers of modest-grained sandstones,which formed high-quality reservoirs in the southern South China Sea region.

信仰为界——19世纪妈祖崇拜与马来半岛南洋华人群体认同变迁

Lasting until this day,Matsu culture has occupied its unique position in the long river of history with its endless vitality.The lengthy historical development of Matsu culture is accompanied by the immigration waves of Chinese,and their awakening of awareness for modern country and ethnicity;and the 19th century is the period for Matsu believers in Nanyang to transit from a group with shared business,dialect,and geological position to an ethnicity group with shared culture identity.This article explores the dynamic transition of the boundary of Matsu believers in Nanyang Chinese society by analyzing a variety of materials,including memoirs written by missionaries of London Missionary Society who went to Nanyang for preaching in the early 19th century as well as periodicals they founded there,remains of inscriptions written in Chinese dating back from middle to late 19th century,and Nanyang newspapers and publications written in Chinese at the end of 19th century.It finds that during that process,the transition of Matsu worship is closely linked to the transition of Nanyang Chinese society and corresponds to the gradual formation of awareness of country and ethnicity among Nanyang Chinese.