Winter coastal upwelling off northwest Borneo in the South China Sea

Winter coastal upwelling off northwest Borneo in the South China Sea （SCS） is investigated by using satellite data, climatological temperature and salinity fields and reanalysis data. The upwelling forms in Decem- ber, matures in January, starts to decay in February and almost disappears in March. Both Ekman trans- port induced by the alongshore winter monsoon and Ekman pumping due to orographic wind stress curl are favorable for the upwelling. Transport estimates demonstrate that the month-to-month variability of Ekman transport and Ekman pumping are both consistent with that of winter coastal upwelling, but Ek- man transport is two times larger than Ekman pumping in January and February. Under the influence of E1 Nino-Southern Oscillation （ENSO）, the upwelling shows remarkable interannual variability： during winter of El Nino （La Nina） years, an anticyclonic （a cyclonic） wind anomaly is established in the SCS, which behaves a northeasterly （southwesterly） anomaly and a positive （negative） wind stress curl anomaly off the north- west Borneo coast, enhancing （reducing） the upwelling and causing anomalous surface cooling （warming） and higher （lower） chlorophyll concentration. The sea surface temperature anomaly （SSTA） associated with ENSO off the northwest Borneo coast has an opposite phase to that off southeast Vietnam, resulting in a SSTA seesaw pattern in the southern SCS in winter.

Theloderma licin McLeod and Ahmad,2007 (Lissamphibia:Anura:Rhacophoridae),a New Frog Record for Borneo

A new record of the rhacophorid frog, Theloderma licin is reported from Gunung Serambu, in the Bau region of western Sarawak, East Malaysia, which comprises the first published record of the species from the Sundaic island of Borneo. The species was previously known from the Malay Peninsula （southern Peninsular Thailand and Peninsular Malaysia）. Species of Theloderma are widespread in mainland and insular Southeast Asia, their arboreal habits perhaps contributing to our perception of rarity.

Oldest Basement(ca.462 Ma)in Indonesian Borneo and its Implication for Early Paleozoic Tectonic Evolution of SE Asia

The lack of preserved basement results in uncertain placements of many terranes in Southeast Asia.Here,we flag the first evidence of the oldest basement in Indonesian Borneo,which can help locate terranes in Borneo on the northern margin of Gondwana in the early Paleozoic and explain the regional tectonic setting of the island.Two schist samples from the Embuoi Complex in the Semitau Block,Northwest Kalimantan yielded zircon U-Pb dates of 453.3±1.9 Ma and 462.4±2.6 Ma,respectively,representing the formation time of the protolith.Petrographic,internal structural and high Th/U ratios of zircons indicate that the protolith of schists is of magmatic origin.The zircons haveεHf(t)values of−4.1 to+1.1 and Hf model ages of 1.37–1.69 Ga,indicating they were derived from a mixed source of juvenile crust with old components.By comparison of zircon age distribution,two-stage Hf model ages andεHf(t)variations of the early Paleozoic igneous rocks from Semitau with those of South China,Tengchong–Baoshan,and Indochina,the Semitau Block was most likely a part of or placed next to the Indochina Block of northern Gondwana during the early Paleozoic.Such a similar tectono-magmatic pattern on northern Gondwana formed a prolonged early Paleozoic arc-related belt associated with subduction of the Proto-Tethyan Ocean.

Characteristics of the Density and Magnetic Susceptibility of Rocks in Northern Borneo and their Constraints on the Lithologic Identification of the Mesozoic Rocks in the Southern South China Sea

Based on the volume magnetic susceptibility and specific gravity measurements and mineral and lithologic identification results for 540 samples,the rock type,density,and magnetic susceptibility of rocks from northern Borneo were analyzed,and the applicability of gravity and magnetic data to the lithologic identification of the Mesozoic strata in the southern South China Sea was assessed accordingly.The results show that there are 3 types and 25 subtypes of rocks in northern Borneo,mainly intermediate-mafic igneous rocks and exogenous clastic sedimentary rocks,with small amounts of endogenous sedimentary rocks,felsic igneous rocks,and metamorphic rocks.The rocks that are very strongly-strongly magnetic and have high-medium densities are mostly igneous rocks,tuffaceous sandstones,and their metamorphic equivalents.The rocks that are weakly magnetic-non-magnetic and have medium-very low densities are mostly conglomerates,sandstones,siltstones,mudstones,and coal.The rocks that are weakly magnetic-diamagnetic and have highmedium densities are mostly limestones and siliceous rocks.The Cenozoic rocks are characterized by low densities and medium susceptibilities;the Mesozoic rocks are characterized by medium densities and medium-high susceptibilities;and the pre-Mesozoic rocks are characterized by high densities and low magnetism.Based on these results and the distribution characteristics of the various rock types,it was found that the pre-Mesozoic rocks produce weak regional gravity anomalies;the Mesozoic sedimentary rocks produce negative regional gravity anomalies;whereas the Mesozoic igneous rocks produce positive regional gravity anomalies;and the Cenozoic igneous rocks produce positive regional gravity anomalies.The regional high magnetic anomalies in the southern part of the South China Sea originate from the Mesozoic mafic igneous rocks and their metamorphic equivalents;and the regional medium magnetic anomalies may be produced by the felsic igneous rocks and their metamorphic equivalents.Accordingly,the identification of the Mesozoic lithology in the southern South China Sea shows that the Mesozoic sedimentary rocks are distributed over a large area of the southern South China Sea.Thus,it is concluded that the Mesozoic strata in this area have the potential for oil and gas exploration.

Gerarda prevostiana(Eydoux and Gervais,1837)(Squamata:Serpentes:Homalopsidae),a New Snake for Borneo

A new record of the homalopsid snake, Gerarda prevostiana is presented from a mangrove-dominated patch in the vicinity of Kampung Bako, Sarawak, East Malaysia, and this comprises the first published record from the Sundaic Island of Borneo. A possible second locality for the species is a ca. 6.68 km site to its northeast, Kampung Buntal, based on an unlocated museum specimen. The species is widespread in mainland Southeast Asia, with additional records to the west （the Indian Subcontinent） and east （the Philippines Archipelago）, but was previously unrecorded from the islands of the Sundas. The secretive habits of the species, including the occupancy of mud lobster （Thalassinia spp.） mounds in mostly inaccessible, swampy habitats may be a reason for its perceived rarity and few published records.

Development of Jacket Platform Tsunami Risk Rating System in Waters Offshore North Borneo

This work details the simulation of tsunami waves generated by seaquakes in the Manila Trench and their effect on fixed oil and gas jacket platforms in waters offshore North Borneo. For this study, a four-leg living quarter jacket platform located in a water depth of 63 m is modelled in SACS v5.3. Malaysia has traditionally been perceived to be safe from the hazards of earthquakes and tsunamis. Local design practices tend to neglect tsunami waves and include no such provisions. In 2004, a 9.3Mw seaquake occurred off the northwest coast of Aceh, which generated tsunami waves that caused destruction in Malaysia totalling US$ 25 million and 68 deaths. This event prompted an awareness of the need to study the reliability of fixed offshore platforms scattered throughout Malaysian waters. In this paper, we present a review of research on the seismicity of the Manila Trench, which is perceived to be high risk for Southeast Asia. From the tsunami numerical model TUNA-M2, we extract computer-simulated tsunami waves at prescribed grid points in the vicinity of the platforms in the region. Using wave heights as input, we simulate the tsunami using SACS v5.3 structural analysis software of offshore platforms, which is widely accepted by the industry. We employ the nonlinear solitary wave theory in our tsunami loading calculations for the platforms, and formulate a platform-specific risk quantification system. We then perform an intensive structural sensitivity analysis and derive a corresponding platform-specific risk rating model.

Detrital zircon U-Pb age perspective on the sediment provenance and its geological significance of sandstones in the Lamandau region, SW Borneo, Indonesia

The Southwest Borneo(SW Borneo)block belongs to Sundaland and is the oldest continental fragment of Borneo that is believed to derive from the Gondwana land.The U-Pb isotopic dating ages of 113 detrital zircons from sandstones of the Ketapang Complex in SW Borneo range from 3298 Ma to 78 Ma,and show six major age populations:2476-2344 Ma,2016-1831 Ma,1296-759 Ma,455-406 Ma,262-210 Ma,and 187-78 Ma.The youngest age of these detrital zircons is 78 Ma,indicating that the maximum depositional age of the sandstones is Campanian.Permian-Late Cretaceous detrital zircons are interpreted as having been derived from the nearby Schwaner Mountains and the Permian-Triassic tin belt granitoids in Southeast Asia(SE Asia).Archean-Carboniferous detrital zircons have a continental Gondwana provenance,with their age spectra similar to those of northwestern Australia,indicating that these zircons could be derived from the orogenic belts and cratons in northwestern and central Australia.The provenance of these detrital zircons in this study indicates the SW Borneo block was located on the northwestern margin of Australia during the Paleozoic,in the region of the Banda Embayment.SW Borneo rifted from Australia and moved northward in the Early Jurassic,and this block was added to Sundaland in the Early Cretaceous.The Luconia-Dangerous Grounds continental fragment derived from East Asia collided with SW Borneo after subduction in the Cretaceous,which induced the widespread magmatism in the Schwaner Mountains in SW Borneo.

Trophic Ecology of Ansonia latidisca at Gunung Penrissen, Sarawak, North-Western Borneo

Dietary data on Ansonia latidisca, the little known Bornean Rainbow Toad, are presented, through an investigation of a population at Gunung Penrissen, Sarawak, Malaysia(north-western Borneo), at elevations between 1,100–1,229 m asl. Standard sampling techniques, including visual encounter surveys, were employed and individuals encountered stomach-flushed, ma rked, a nd released. The volume of food ingested by adults, apart from large females, did not vary monthly, and there was no significant difference between wet and dry periods, the dominance index between the two periods showing no significant difference, indicating that seasonal variation does not affect the dietary constitution of the species across months. The mean longest prey was recovered from a female in March, during the end of the wet season. Larger individuals did not consume larger prey in the species, although larger females did harvest the largest insects, and as may be expected, had fewer prey items in their stomachs at the time. Males fed on fewer prey items than females, the adult male diet predominantly comprised of members of the Hymenoptera, including formicids(ants), as indicated by percentage frequency of occurrence of 78.69, while for adult females, equivalent figure was 90.70. Coleopterans(beetles) were found secondary in importance(48.8% in females, 5.85% in males), the rest categorized as tertiary. Plant items(including bryophytes) had a high frequency of occurrence(23.3% in females, 4.64% in males). Females examined in the month of July had voluminous stomach contents, and may have eaten more to increase fat reserves for breeding in the upcoming wet season. Since the diet of all size classes consisted of hymenopterans(ants) and coleopterans, the study species is here considered to have a narrow food preference, and consequently, is a dietary specialist.

A New Epi‑neoverrucosane‑type Diterpenoid from the Liverwort Pleurozia subinfata in Borneo

New bioactive 13-epi-neoverrucosane diterpenoid,5β-acetoxy-13-epi-neoverrucosanic acid(1)along with three known secondary metabolites,13-epi-neoverrucosan-5β-ol(2),chelodane(3)and(E)-β-farnesene(4)were isolated from the MeOH extract of east Malaysia’s liverwort Pleurozia subinfata.The chemical structure of new compound was elucidated by the analyses of its spectroscopic data(FTIR,NMR and HR-ESI-MS).These epi-neoverrucosane-type compounds seem to be notable chemosystematic markers for P.subinfata in Borneo.Compound 3 was widespread in marine sponges however this is the frst record for 3 to be found in liverwort.These metabolites were tested for their antifungal potentials against selected fungi from the marine environment.Compound 1 exhibited efective antifungal activity against Lagenidium thermophilum.

Rediscovery and Redescription of Tropidophorus micropus van Lidth de Jeude,1905(Squamata:Sauria:Scincidae)from Sarawak,East Malaysia(Borneo)

Tropidophorus micropus van Lidth de Jeude, 1905, described from the upper Mahakkam River, Kalimantan, Indonesia, is here redescribed, based on new material from upper Baleh, Sarawak, East Malaysia（Borneo）, collected after over 100 years. The new locality is ca. 94 km to the north of the type locality, and comprises a new national record.

马来西亚Borneo制浆项目依旧毫无起色

新加坡的亚洲浆纸(APP)日前指出,自1998年来马来西亚的Borneo制浆项目一直被无限期推迟,项目的启动问题依然未见起色.

The gradual subduction-collision evolution model of Proto-South China Sea and its control on oil and gas

This study involved outcrop,drilling,seismic,gravity,and magnetic data to systematically document the geological records of the subduction process of Proto-South China Sea(PSCS)and establish its evolution model.The results indicate that a series of arc-shaped ophiolite belts and calcalkaline magmatic rocks are developed in northern Borneo,both of which have the characteristics of gradually changing younger from west to east,and are direct signs of subduction and collision of PSCS.At the same time,the subduction of PSCS led to the formation of three accretion zones from the south to the north in Borneo,the Kuching belt,Sibu belt,and Miri belt.The sedimentary formation of northern Borneo is characterized by a three-layer structure,with the oceanic basement at the bottom,overlying the deep-sea flysch deposits of the Rajang–Crocker group,and the molasse sedimentary sequence that is dominated by river-delta and shallow marine facies at the top,recording the whole subduction–collision–orogeny process of PSCS.Further,seismic reflection and tomography also confirmed the subduction and collision of PSCS.Based on the geological records of the subduction and collision of PSCS,combined with the comprehensive analysis of segmented expansion and key tectonic events in the South China Sea,we establish the“gradual”subduction-collision evolution model of PSCS.During the late Eocene to middle Miocene,the Zengmu,Nansha,and Liyue–Palawan blocks were separated by West Baram Line and Balabac Fault,which collided with the Borneo block and Kagayan Ridge successively from the west to the east,forming several foreland basin systems,and PSCS subducted and closed from the west to the east.The subduction and extinction of PSCS controlled the oil and gas distribution pattern of southern South China Sea(SSCS)mainly in three aspects.First,the“gradual”closure process of PSCS led to the continuous development of many large deltas in SSCS.Second,the deltas formed during the subduction–collision of PSCS controlled the development of source rocks in the basins of SSCS.Macroscopically,the distribution and scale of deltas controlled the distribution and scale of source rocks,forming two types of source rocks,namely,coal measures and terrestrial marine facies.Microscopically,the difference of terrestrial higher plants carried by the delta controlled the proportion of macerals of source rocks.Third,the difference of source rocks mainly controlled the distribution pattern of oil and gas in SSCS.Meanwhile,the difference in the scale of source rocks mainly controlled the difference in the amount of oil and gas discoveries,resulting in a huge amount of oil and gas discoveries in the basin of SSCS.Meanwhile,the difference of macerals of source rocks mainly controlled the difference of oil and gas generation,forming the oil and gas distribution pattern of“nearshore oil and far-shore gas”.

印尼西婆罗洲早白垩世Mensibau花岗岩类的成因及构造意义

婆罗洲西部(印尼)在中生代期间处于特提斯构造域和古太平洋构造域交汇地带,是全球少有的多重板块动力学体制既有先后叠加又有同时复合的独特大地构造单元。因此,该区相关花岗岩类成因及构造背景的研究对揭示东南亚构造—岩浆演化历史及多重构造体制叠合造山作用下的岩浆演化机制至关重要。笔者等对西婆罗洲Mensibau岩基的花岗岩类进行了锆石U-Pb年代学、元素地球化学和Sr-Nd-Hf同位素分析。其中,石英二长岩和钾长花岗岩样品的LA-ICP-MS锆石U-Pb同位素年龄分别为126.9±2.1 Ma和141.8±2.6 Ma,表明岩体形成于早白垩世,岩浆活动至少持续了15 Ma。Mensibau花岗岩类具有高SiO2(67.5%~73.3%)、高K2O (4.3%~5.4%)和低P2O5(0.07%~0.14%)的元素含量特征,铝饱和指数(A/CNK)为0.92~1.06,并且含角闪石,属准铝质—弱过铝质I型花岗岩类。这些花岗岩类具有轻稀土元素(LREEs)富集和重稀土元素(HREEs)亏损,弱的负铕异常(δEu=0.65~1.00),以及富集大离子亲石元素(Rb、Th、U和K)和亏损高场强元素(Nb、Ta和Ti)特征,显示出岛弧花岗岩的地球化学特征。此外,Mensibau花岗岩类具有正的εNd(t)值(+3.14~+4.09)、低的[n(87Sr)/n(86Sr)]i值(0.70420~0.70424)和高的锆石εHf(t)值(+9.30~+13.87),表明岩浆来源于新生镁铁质地壳的部分熔融。综合区域地质背景研究表明,发育在俯冲—增生杂岩上的Mensibau花岗岩类可能为受两种构造体制(古太平洋和新特提斯洋)叠合俯冲作用下的新生地壳来源的增生弧岩浆岩,证实了西婆罗洲地区在早白垩世期间经历了重要的增生造山过程。

Causes of Cretaceous subduction termination below South China and Borneo:Was the Proto-South China Sea underlain by an oceanic plateau?

The South China,Indochina,and Borneo margins surrounding the South China Sea contain long-lived arcs that became inactive at approximately 85 Ma,even though an embayment of oceanic crust(the‘Proto-South China Sea’)remained in the intervening region.This oceanic crust eventually subducted in the Cenozoic below Borneo and the Cagayan arc,while the modern South China Sea opened in its wake.To investigate the enigmatic cessation of Mesozoic subduction below South China and Borneo,we studied a fragment of oceanic crust and overlying trench-fill sediments that accreted to NW Borneo during the final stages of Paleo-Pacific subduction.Based on radiolarian biostratigraphy of cherts overlying the pillow basalts and detrital zircon geochronology of the trench-fill,we constrained the minimum age of the oceanic crust during accretion to 40 Ma.This shows that subduction cessation was not related to ridge subduction.Geochemical analysis of pillow basalts revealed an enriched mid-ocean ridge basalt signature comparable to oceanic plateaus.Using paleomagnetism,we show that this fragment of oceanic crust was not part of the Izanagi Plate but was part of a plate(the‘Pontus’Plate)separated from the Izanagi Plate by a subduction zone.Based on the minimum 40 Ma age of the oceanic crust and its geochemistry,we suggest that Mesozoic subduction below South China and Borneo stopped when an oceanic plateau entered the trench,while the eastern plate margin with the Izanagi Plate remained active.We show how our findings offer opportunities to restore plate configurations of the Panthalassa-Tethys junction region.

GC法测定特灵眼药中冰片的含量

目的建立毛细管GC法测定特灵眼药中冰片含量测定方法。方法采用DB-WAX毛细管柱,FID检测器,乙酸乙酯为溶剂。结果平均回收率为96.4%;RSD为0.63%。结论本方法简便,结果可靠,可作为该制剂质量控制标准。

麝香与冰片不同配比对急性脑缺血模型小鼠血脑屏障通透性的影响

目的:考察麝香与冰片配伍对急性脑缺血模型小鼠血脑屏障通透性的影响。方法:采用双侧颈总动脉结扎法制造急性脑缺血模型,通过测定渗出脑血管外的伊文思蓝含量分析药物对血脑屏障通透性的影响。结果:假手术组与吐温对照组脑组织伊文思蓝含量无显著差异(P>0.05);模型组与假手术组及吐温对照组比较,伊文思蓝含量明显升高(P<0.05);与模型组比较,各给药组脑组织中伊文思蓝含量均有所降低,其中,麝香与冰片1∶2、1∶3配伍组的伊文思蓝含量显著降低(P<0.05)。结论:麝香与冰片配伍可降低小鼠缺血状态下血脑屏障的通透性,提示二者配伍能调节病理状态下的血脑屏障而起到保护作用。

婆罗洲地质构造特征及其对南海南部盆地的影响

南海南部曾母、文莱—沙巴盆地油气资源丰富,已发现一大批油气田及含油气构造。曾母盆地南部与文莱—沙巴盆地油气的生成、运移和聚集与婆罗洲地块息息相关。婆罗洲地块地质特征复杂,自古新世开始,古南海逐渐消失,与婆罗洲地块发生碰撞,中新世开始隆升造山。在这种地质背景下,婆罗洲拉让河和巴兰河为曾母盆地南部与文莱—沙巴盆地的主要物源,发育三角洲相、滨浅海相、浊积扇相、浅海相砂岩储层;同时,压扭型构造发育,不仅形成断块与背斜型油气藏,同时具有良好的油气运移条件。

婆罗洲晚中生代岩浆弧及陆缘俯冲汇聚体制

婆罗洲地处2大构造域结合部,Schwaner岩浆弧和Meratus、Lupar俯冲杂岩是其显著的地质特征,它们与晚中生代特提斯域或/和古太平洋域的板块俯冲密切相关。婆罗洲中生代地质现有研究程度不高,缺乏地质、地球化学和地球物理多学科综合研究,缺乏与周边区域地质对比研究,制约了对婆罗洲岩浆弧演变及板块俯冲体制的整体认识。关于婆罗洲晚中生代岩浆弧,或强调与特提斯洋向北西俯冲婆罗洲有关,或认为古南海向南俯冲婆罗洲有关,或作为两者联合俯冲控制的产物。前白垩纪SW婆罗洲的基底属性,或认为亲缘于华夏地块,或归属巽他大陆的东延部分,或认为是冈瓦那大陆裂解而来的外来块体。今后研究应加强海陆结合、多学科大区域综合对比,重点围绕岩浆弧、蛇绿岩和俯冲杂岩、区域大断裂和盆地沉积等内容,形成婆罗洲及邻区晚中生代陆缘汇聚体制和2大构造域关系的综合认识,也是深化认识南海中生界弧盆结构、盆地原型及其油气勘探潜力的重要环节。

从出走台湾到回归雨林的婆罗洲之子——马华旅台作家张贵兴小说精神流变的分析

张贵兴的早期小说曾受到台湾文坛热捧,但其创作中的异质风格与台湾文坛创作风气是不同的。从留台生文学的青涩模仿,到不同经验的书写实践,再到自成一脉的雨林书写,他用自己的笔墨展现出自己创作生涯中的不同的艺术实践过程,后期的南洋雨林魔幻世界的书写,集合象征、寓言和历史再现于一体,展现出一位旅台马华作家对原乡书写的不懈追求。

气相色谱法测定复方丹参滴丸中冰片的含量

目的 :分析复方丹参滴丸中挥发性成分冰片的含量。方法 :采用气相色谱法 ,用石英毛细柱 ,固定液用交联苯甲基聚硅氧烷 ,氮气为载气测定。结果 :所采用的测定方法进行了线性回归考察 ,表明冰片在0.1～0.6mg/ml范围内具有良好的线性关系。结论 :经精密度试验、稳定性试验和回收率试验。并经样品含量的测定 ,表明所采用方法重现性较好 ,为该药品的质量控制提供了一个参考的方法。