bluuebunny/crossref_metadata_2025_split huggingface dataset:
Typology of Natural Hazards and Assessment of Associated Risks in the Mount Bambouto Caldera (Cameroon Line, West Cameroon)
Authors: ZANGMO Ghislain T. , KAGOU Armand D. , NKOUATHIO David G. , WANDJI Pierre 
Published: August 2010

Abstract:Mount Bambouto is a polygenic stratovolcano of the Cameroon Volcanic Line, built between 21 Ma and 4.5 Ma. It is situated approximately 200 km NE of Mount Cameroon, between 09° 55′ and 10°15′ longitude east and, 05°25′ and 05°50′ latitude north. The volcano covers an area of 500 km2 and culminates at 2740 m at Mélétan dome and bears a collapsed caldera at the summit (13 × 8 km). Mount Bambouto is characterized by several natural hazards of different origins: meteorological, such as landslides and rock falls; anthropogenic, such as bushfires, tribal wars and deforestation; and volcanological, such as volcanic eruption. The thematic map shows that 55–60% of the caldera has high probability of occurrence of mass movement. The caldera has a high population density (3000 inhabitants), which increases the level of risk, evaluated at approximately $US3.8 million for patrimony, 3000 civilian deaths and destruction of biodiversity.
Structure, Orientation and Finite Element Analysis of the Tail Club of Mamenchisaurus hochuanensis
Authors: Lida XING , Yong YE , Chunkang SHU , Guangzhao PENG , Hailu YOU 
Published: August 2010

Abstract:The structure and orientation of the posterior extremity (tail club) of the caudal vertebrae of Mamenchisaurus hochuanensis Young and Chao, 1972 from the Upper Jurassic Shangshaximiao Formation has been analyzed to determine the tail club function using Finite Element Analysis. Of the four caudal vertebrae composing the tail club, the second largest (C“1”) was probably the most proximal, and is fixed with the preceding sequence of the caudal vertebrae, whereas the smallest (C“4”) is free and forms the termination of the tail club. Our analysis also suggests that the tail club is more efficient in lateral swinging rather than up‐and‐down motion, and that the best region for the tail club to impact is at the spine of the largest of the four caudals (C“2”), with a maximum load for impact at about 450 N. The tail club of Mamenchisaurus hochuanensis probably also had limitations as a defense weapon and was more possibly a sensory organ to improve nerve conduction velocity to enhance the capacity for sensory perception of its surroundings.
Tectonic and Hydrocarbon Accumulation Elements Characteristics of the Tethyan Realm in South China
Authors: Yixin YU , Liangjie TANG , Jinyin YIN , Li DONG , Pengwan WANG , Yan ZHOU 
Published: August 2010

Abstract:The evolution of the global Tethys Sea can be classified into three stages, Proto‐Tethys, Paleo‐Tethys and Neo‐Tethys. The Tethyan realm has distinctive features of zonations and segmentations along north‐south and east‐west, respectively, and has variable richness in oil and gas. The petroleum geological conditions of Tethys are complicated, partly represented by multi‐layer of source and seal rocks, and reservoirs. The hydrocarbon accumulation elements and periods of the Tethyan realm show gradually younger from west to east and north to south. South China is located in the north belt and Yangtze segment of the Tethyan realm, and its polycyclic tectonic movements were governed by the Tethyan and Pacific realms. The blocks in South China rotated clockwise and counter‐clockwise during their drift northward from Gondwana. The belts and segmentations of Tethys in South China are also clear, with six tectonic belts including: Chuxiong‐Sichuan; middle Guizhou‐Hunan‐Hubei; lower Yangtze; Xuefeng‐Jiangnan; Guangxi‐Hunan‐Jiangxi; and Cathaysia. Numerous faults, including compressional, compressional‐shear, extensional, extensional‐shear and shear are well developed in South China. The fault strikes are mainly NE, NW and NS, in which the NE is the dominant direction. Lower, middle and upper hydrocarbon assemblages, respectively corresponding to Proto‐, Paleo‐ and Neo‐Tethys, formed in the Tethyan realm of South China with the lower and middle having excellent hydrocarbon accumulation conditions. An integrated analysis of tectonic evolution, superimposed deformation and later hydrocarbon preservation shows that during the Neo‐Tethyan stage in South China, continental sediments were deposited and experienced intense tectonic deformation, which had resulted in different hydrocarbon pool‐forming features from those of the Neo‐Tethyan realm.
Upwelling Process of the Western Himalaya Mountains: Height and Velocity Estimation Evidenced by Formation and Evolution of the Zanda Basin, Tibet, China
Authors: ZHU Dagang , MENG Xian'gang , SHAO Zhaogang , YANG Chaobin , HAN Jian'en , YU Jia , MENG Qingwei , LÜ Rongping 
Published: August 2010

Abstract:Based on field geological survey, stratigraphic section measurement and indoor comprehensive investigation, the Zanda Basin's tectonic location in the Himalaya Plate was ascertained, and the formation and evolution of the Zanda Basin during the Pliocene to Early Pleistocene was classified as six stages: (a) primary rift‐faulting stage, (b) quick rift‐faulting Stage, (c) intensive rift‐faulting stage, (d) stasis stage, (e) secondary rift‐faulting stage, and (f) secondary quick rift‐faulting stage. Based on this six‐staged formation‐evolution theory of the Zanda Basin, the upwelling process of the Western Himalaya Mountains from the Pliocene to Early Pleistocene was classified as the following five stages: (a) slow upwelling stage (5.4–4.4 Ma), (b) mid‐velocity upwelling stage (4.4–3.5 Ma), (c) quick upwelling stage (3.5–3.2 Ma), (d) upwelling‐ceasing stage (3.2–2.7 Ma), and (e) quick upwelling stage (2.7 Ma). Research has shown that in the duration from the Early Pliocene (4.7 Ma) to the End of Pliocene (2.67 Ma), which lasted 2.03 million years, the Himalaya Mountains had uplifted 1500 m at a velocity of 0.74 mm/a; this belongs to a mid‐velocity upwelling. During the 1.31 million years in the Early Stage of the Early Pleistocene, the Himalaya Mountains had risen up another 1500 m at a velocity of 1.15 mm/a; this is a rather quick upwelling. All of these data have shown that the upwelling of the Western Himalaya Mountains is along a complicated process with multi‐stages, multi‐velocities, and non‐uniformitarian features.
Neoproterozoic Tectonic Setting of Southeast China: New Constraints from SHRIMP U‐Pb Zircon Ages and Petrographic Studies on the Mamianshan Group
Authors: WU Ganguo , YU Xinqi , DI Yongjun , ZHANG Da 
Published: August 2010

Abstract:Precambrian tectonic history of Zhejiang, Fujian, and Jiangxi provinces of south China is important for understanding the tectonic evolution of South China but its magmatic activity, petrogenesis, stratigraphic sequence of the Mamianshan Group is still strongly controversial. Here we present new sensitive high resolution ion micro‐probe (SHRIMP) U‐Pb zircon geochronological data for the Mamianshan Group and petrographical data to constrain the tectonic framework of the regions. Our results showed that the SHRIMP U‐Pb zircon age of green schists of the Dongyan Formation is 796.544.3 Ma, the Daling Formation is 756.2±7.2 Ma, and mica‐quartz schist of the Longbeixi Formation is 825.5±9.8 Ma. These data indicate that the Mamianshan Group was formed not in the Mesoproterozoic, but in the Neoproterozoic and its stratigraphic sequences should be composed of Longbeixi, Dongyan, and Daling Formations from the bottom to the top. Rocks from this Group, from Zhejiang, Fujian and Jiangxi provinces, constituted the upper basement of the Cathaysia Block that overlay the lower basement of the Mayuan Group. Detailed petrographic studies demonstrate that the amphibole schists of the Dongyan Formation in the Mamianshan Group were formed within an intra‐arc rift setting rather than a continental rift as previously suggested. Rather, this island‐arc type formation was developed by collision and/or subduction between various blocks resulting from the breakup of the supercontinent Rodinia at c.850–750 Ma. The Zhuzhou conglomerate, distributed near Dikou Town, Jian'ou City, Fujian Province and previously considered as evidence of the Mesoproterozoic Dikou movement, is shown here not to be the basal conglomerate above the angular unconformity between the upper and lower basements. Our conclusions have important implications for understanding the Precambrian tectonics of South China.
Protophyllocladoxylon jingyuanense sp. nov., a Gymnospermous Wood of the Serpukhovian (Late Mississippian) from Gansu, Northwest China
Authors: ZHANG Yi , WANG Jun , LIU Lujun , LI Nan 
Published: August 2010

Abstract:A new species of gymnospermous fossil wood, Protophyllocladoxylon jingyuanense sp. nov., is described from the lower part of the Tsingyuan Formation (Serpukhovian/Late Mississippian), near the coal mine of Ciyao, Gansu, northwestern China. The specimen is preserved only in silicified secondary xylem, while growth rings are absent Pits in radial tracheidal walls are araucaroid in type, uniseriate, occasionally biseriate. Xylem rays are homogeneous, uniseriate, occasionally biseriate. Cross‐field pits are simple, large, one to two in number. Axial parenchyma is absent. The anatomical characters and geographic distribution of Protophyllocladoxylon woods through geological ages are documented. Those species with axial parenchyma and without growth rings live in warm climate, whereas the species without axial parenchyma and with growth rings are present either in warm or cool climate. The ideal living climate for Protophyllocladoxylon woods is warm and wet. Our new species, as a fossil wood of Early Carboniferous, is likely the earliest known species of Protophyllocladoxylon.
Gas Hydrates in the Qilian Mountain Permafrost, Qinghai, Northwest China
Authors: ZHU Youhai , ZHANG Yongqin , WEN Huaijun , LU Zhenquan , JIA Zhiyao , LI Yonghong , LI Qinghai , LIU Changling , WANG Pingkang , GUO Xingwang 
Published: August 2010

Abstract:Qilian Mountain permafrost, with area about 10×104 km2, locates in the north of Qinghai‐Tibet plateau. It equips with perfect conditions and has great prospecting potential for gas hydrate. The Scientific Drilling Project of Gas Hydrate in Qilian Mountain permafrost, which locates in Juhugeng of Muri Coalfield, Tianjun County, Qinghai Province, has been implemented by China Geological Survey in 2008–2009. Four scientific drilling wells have been completed with a total footage of 2059.13 m. Samples of gas hydrate are collected separately from holes DK‐1, DK‐2 and DK‐3. Gas hydrate is hosted under permafrost zone in the 133–396 m interval. The sample is white crystal and easily burning. Anomaly low temperature has been identified by the infrared camera. The gas hydrate‐bearing cores strongly bubble in the water. Gas‐bubble and water‐drop are emitted from the hydrate‐bearing cores and then characteristic of honeycombed structure is left The typical spectrum curve of gas hydrate is detected using Raman spectrometry. Furthermore, the logging profile also indicates high electrical resistivity and sonic velocity. Gas hydrate in Qilian Mountain is characterized by a thinner permafrost zone, shallower buried depth, more complex gas component and coal‐bed methane origin etc.
A New Juvenile Specimen ofLufengosaurus HueneiYoung, 1941 (Dinosauria: Prosauropoda) from the Lower Jurassic Lower Lufeng Formation of Yunnan, Southwest China
Authors: SEKIYA Tom , DONG Zhiming 
Published: August 2010

Abstract:A skull and a series of associated cervical vertebrae (ZLJ0112) discovered from the Lower Lufeng Formation (Lower Jurassic) are determined as a juvenile specimen ofLufengosaurus hueneiYoung 1941 based on amended autapomorphies. Differences between ZLJ0112 and the holotype (sub‐adult specimen) are considered as ontogenetic characteristic changes ofL. huenei.Since some of these differences are present in other prosauropod dinosaurs (i.e., forms of the maxillary vascular foramen are irregular; the frontal contribution to the dorsal margin of the orbit is substantial; the frontal contribution to the supratemporal fossa is absent; the supratemporal fenestra is visible in lateral view; the supraoccipital inclined at 75 degrees; the parasphenoid rostrum lies level with the occipital condyle; the retroarticular process is short; the axial postzygapophysis project caudally beyond the end of the centrum) they may be common ontogenetic changes in prosauropod dinosaurs.
Paleogeographical Distribution of Mesozoic Palaeontinidae (Insecta, Hemiptera) in China with Description of New Taxa
Authors: WANG Bo , ZHANG Haichun , FANG Yan 
Published: August 2010

Abstract:Until now, all Chinese palaeontinids have come from northern China and are more diverse than any other hemipterous insects in the Mesozoic. Most palaeontinids have been discovered from the area encompassing northern Hebei, the Ningcheng area of Inner Mongolia and western Liaoning. The difference in ubiquity of fossil records between northern and southern China is probably related to taphonomical and collecting bias. Records of Early and Late Jurassic palaeontinids are very scarce. The highest diversity of palaeontinid species occurs in the Middle Jurassic of Daohugou Lagerstätte. Early Cretaceous palaeontinids of China are restricted to the typical distribution of Jehol Biota. Palaeontinodes sp. is described from the Lower Cretaceous Yixian Formation of Yangshuwanzi, Inner Mongolia and is the only Palaeontinodes specimen from the Cretaceous. Plachutella exculpta Zhang, 1997 from the Lower Jurassic Badaowan Formation of Karamai, Xinjiang is re‐described and some previously reported species of this genus are discussed.
Late Mesozoic Chresmodids with Forewing from Inner Mongolia, China (Polyneoptera: Archaeorthoptera)
Authors: ZHANG Xinwen , REN Dong , PANG Hong , SHIH Chungkun 
Published: August 2010

Abstract:Three new species of Chresmodidae are described. They belong to two different genera: Chresmoda multinervis sp. nov., Chresmoda shihi sp. nov. and Jurachresmoda sanyica sp. nov. A study of the forewing venation is provided. Longitudinal veins are mostly parallel; costal area is broad at the basal and narrowing distally; ScP is probably extending close to the wing apex; R is parallel at length to ScP; MA is running close to R, with two long parallel branches; MA branched‐off basally; while MP is not branched until the middle of the wing. However, the important basal part of MP and CuP is poorly preserved. In addition, unique fringing hairs on the mid legs of C. shihi sp. nov. and J. sanyica sp. nov. are described and compared with Jurachresmoda gaskelli Zhang, Ren and Shih, 2008.
Xingxueanthus: An Enigmatic Jurassic Seed Plant and Its Implications for the Origin of Angiospermy
Authors: WANG Xin , WANG Shijun 
Published: August 2010

Abstract:The origin of angiosperms has been tantalizing botanists for centuries. Despite the efforts of palaeobotanists, most of the pre‐Cretaceous angiosperms are regarded either non‐convincing or misdated. The applications of SEM and LM (light microscope) enable us to recognize a coalified fossil plant, Xingxueanthus sinensis gen. et sp. nov., from the Haifanggou Formation (Middle Jurassic, >160 Ma) in western Liaoning, China. Xingxueanthus is an “inflorescence” with more than 20 female units spirally arranged. Each female unit is situated in the axil of a bract. The female unit is composed of an ovule‐container and a style‐like projection at the top. There is a vertical column bearing several ovules in the ovule‐container. The general morphology and the internal structure of Xingxueanthus distinguish itself from any known fossil and extant gymnosperms, and its structures are more comparable to those of angiosperms. Xingxueanthus, if taken as a gymnosperm, would represent a new class, demonstrate an evolutionarily advanced status of ovule‐protection in gymnosperms never seen before, and provide new insights into the origin of angiospermy. Alternatively, if taken as an angiosperm, together with Schmeissneria, it would increase the diversity of Jurassic angiosperms, which has been underestimated for a long time, and suggest a much earlier origin of angiospermy than currently accepted.
Mineral Geochemical Compositions of Tourmalines and Their Significance in the Gejiu Tin Polymetallic Deposits, Yunnan, China
Authors: JIA Runxing , FANG Weixuan , HU Ruizhong 
Published: August 2010

Abstract:The Gejiu tin polymetallic deposits are located in the southeastern part of Yunnan Province in China. A detailed electronic microprobe study has been carried out to document geochemical compositions of tourmalines from the deposits. The results indicate a systematic change of mineral geochemical compositions, which might be used as a mineral geochemical tracer for post‐magmatic hydrothermal fluid, basin fluid and their mixture. The tourmalines from granite are schorl with Fe/(Fe+Mg) ratios of 0.912–1.00 and Na/(Na+Ca) ratios of 0.892–0.981. Tourmalines as an inclusion in quartz from the ore bodies are dravite with Fe/(Fe+Mg) ratios of 0.212–0.519 and Na/ (Na+Ca) ratios of 0.786–0.997. Tourmalines from the country rocks are dravite with Fe/(Fe+Mg) ratios of 0.313–0.337 and Na/(Na+Ca) ratio of 0.599–0.723. Tourmalines from cassiterite‐tourmaline veins that occur in crannies within the country rocks show distinct optical zoning with alternate occurrence of dravite and schorl, Fe/(Fe+Mg)=0.374–0.843, Na/(Na+Ca)=0.538–0.987. It suggests that schorl in granite and dravite in carbonatite are related to magmatic fluid and basin fluid respectively. When magmatic fluid rose up and entered into crannies of the country rocks, consisting mainly of carbonatite, basin fluid would be constantly added to the magmatic fluid. The two types of fluid were mixed in structural crannies of the sedimentary basin accompanied with periodic geochemical osculations to form material records in chemical composition zonings of tourmalines.
Crustal Composition of China Continent Constrained from Heat Flow Data and Helium Isotope Ratio of Underground Fluid
Authors: WANG Yang , SUN Zhiming 
Published: August 2010

Abstract:Based on conservation of energy principle and heat flow data in China continent, the upper limit of 1.3 μW/m3 heat production is obtained for continental crust in China. Furthermore, using the data of heat flow and helium isotope ratio of underground fluid, the heat productions of different tectonic units in China continent are estimated in range of 0.58–1.12 μW/m3 with a median of 0.85 μW/m3. Accordingly, the contents of U, Th and K2O in China crust are in ranges of 0.83–1.76 μg/g, 3.16–6.69 μg/g, and 1.0%–2.12%, respectively. These results indicate that the abundance of radioactive elements in the crust of China continent is much higher than that of Archean crust; and this fact implies China's continental crust is much evolved in chemical composition. Meanwhile, significant lateral variation of crustal composition is also exhibited among different tectonic units in China continent. The crust of eastern China is much enriched in incompatible elements such as U, Th and K than that of western China; and the crust of orogenic belts is more enriched than that of platform regions. It can also be inferred that the crusts of eastern China and orogenic belts are much felsic than those of western China and platform regions, respectively, derived from the positive correlation between the heat production and SiO2 content of bulk crust. This deduction is consistent with the results derived from the crustal seismic velocity data in China. According to the facts of the lower seismic velocity of China than the average value of global crust, and the higher heat production of China continent compared with global crust composition models published by previous studies, it is deduced that the average composition models of global continent crust by Rudnick and Fountain (1995), Rudnick and Gao (2003), Weaver and Tarney (1984), Shaw et al. (1986), and Wedepohl (1995) overestimate the abundance of incompatible elements such as U, Th and K of continental crust.
Geologic Characteristics of Volcanic Hydrocarbon Reservoirs and Exploration Directions in China
Authors: ZOU Caineng , ZHU Rukai , ZHAO Wenzhi , JIA Chengzao , ZHANG Guangya , YUAN Xuanjun , ZHAO Xia , WEN Baihong 
Published: August 2010

Abstract:Volcanic rocks are distributed widely in China, which are important exploration targets. By analyzing many discovered volcanic hydrocarbon reservoirs all over the world, the authors summarized the geologic characteristics of the formation of volcanic hydrocarbon reservoirs in China, and gave further exploration directions and advices. (1) There are mainly Carboniferous‐Permian, Jurassic‐Cretaceous, Paleogene‐Neogene volcanic rocks in oil‐ and gas‐bearing basins in China, which are mainly distributed in the Junggar Basin, Songliao Basin, Bohai Bay Basin, etc. There are mainly intermediate rocks and acidic rocks in east China, and intermediate rocks and basic rocks in west China. They primarily develop in intracontinental rift settings and island are environments. (2) Porefissure reservoirs are distributed widely in basins, which are volcanic rocks mainly in explosive and effusive facies. (3) Volcanic hydrocarbon reservoirs are chiefly near‐source lithostratigraphic hydrocarbon reservoirs, and the oil and gas accumulation is predominantly controlled by lithotypes, faults and structural positions. (4) Deep‐seated oil and gas reservoirs in the Songliao Basin and Carboniferous volcanic hydrocarbon reservoirs in the Junggar Basin are potential giant volcanic gas provinces, the volcanic hydrocarbon reservoirs in the Bohai Bay Basin and Santanghu Basin are favorable for oil and gas reserves increase, and volcanic rocks in the Turpan Basin, Sichuan Basin, Tarim Basin have exploration potentiality. (5) The technology series of oil and gas exploration in volcanic rocks have been preliminarily formed.
Karren of Mushroom Mountain (Junzi Shan) in the Eastern Yunnan Ridge, Yunnan, China: Karstological and Tourist Attraction
Authors: KNEZ Martin , SLABE Tadej 
Published: August 2010

Abstract:Mushroom Mountain karren with predominantly flat tops that formed along the stylolites and bedding planes dictated the special features of this karst landscape. Their features and rock relief clearly reflect the geological conditions and development. The subsoil karren with conical tops dissected by subsoil rock relief were exposed from beneath the soil. Below tree vegetation, the subsoil karren are to a great extent covered by moss and lichen, under which they acquire their characteristic shape. On the bare surface they were reshaped by rainwater that carves flutes and solution pans. The old cave that opens below the top of one of the cones reveals the period before its dissection into hills and cones when this part of the karst aquifer was still deep under the water table.