bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structural Characteristics of the Basement beneath Qiangtang Basin in Qinghai‐Tibet Plateau: Results of Interaction Interpretation from Seismic Reflection/Refraction Data
Authors: Qiusheng LI , Rui GAO , Shaoying FENG , Zhanwu LU , Hesheng HOU , Ye GUAN , Pengwu LI , Haiyan WANG , Zhuo YE , Xiaosong XIONG , Jinkai LIU , Rizheng HE 
Published: April 2013

Abstract:The studies on configuration, character/property of the basement of Qiangtang basin is helpful for evaluating petroleum and nature gas resources as well as understanding the basin evolvement. Recently a moderate to high‐grade metamorphic gneiss rock was found underlying beneath very low metamorphic Ordovician strata in Mayer Kangri to the north of the central uplift. That fact actually proved existence of the crystalline basement just the distribution and structures of pre‐Paleozoic crystalline basement still remain puzzle. In recent years a number of active sources deep seismic profiling, to aim at lithospheric structure of northern Tibet and petroleum resources of the Qiangtang basin, had been conducted that make it possible to image the structure of the basement of the Qiangtang. Near vertical reflection profiles, included those acquired previously and those during 2004 to 2008, have been utilized in this study. By through the interaction process and interpretation between the reflection profiles and the wide‐angle profile, a model with the detailed structure and velocity distribution from surface to the depth of 20 km of Qiangtang basin has been imaged. Based on the results and discussions of this study, the preliminary conclusions are as follows: (1) The velocity structure section (∼20 km) that is interactively constrained by the refraction and reflection seismic data reveals that the sedimentary stratum gently lie until 10 km in the south Qiangtang basin. (2) The basement consists of fold basement (the upper) and crystalline basement (the lower). The fold basement buried at the average depth of 6 km with a velocity of 5.2–5.8 km/s. The shallowest appear at range of the central uplift. The crystalline basement is underlying beneath the fold basement at the average depth of 10 km with a velocity of 5.9–6.0 km/s except near Bangong‐Nujiang suture. (3) The high‐velocity body at the depth range of 3–6 km of the central uplift is considered as a fragment of the crystalline basement that perhaps was raised by Thermal or deformation. (4) The lower‐consolidated fold basement show more affinity of Yangtze block but the crystalline basement seems more approximate to Lhasa terrene in geophysical nature. We have attempted to improve the resolution and reliability by interaction of the active seismic data and prove it effective to image complex basement structure. It will be a potential to process the piggy‐back acquisition data and has wide prospects.
Study on the Tectonic Setting for the Ophiolites in Xigaze, Tibet
Authors: Peisheng BAO , Li SU , Jun WANG , Qingguo ZHAI 
Published: April 2013

Abstract:The Xigaze ophiolite is located in the middle section of the Yarlung Zangbo River ophiolite belt and includes a well‐preserved sequence section of seven ophiolite blocks. The relatively complete ophiolitic sequence sections are represented by Jiding, Dejixiang, Baigang, and Dazhuqu ophiolites and consist of three–four units. The complete ophiolite sequence in order from the bottom to top consists of mantle peridotite, cumulates, sheeted sill dike swarms, and basic lavas±radiolarian chert. These cumulates are absent in the remaining blocks of Dejixiang and Luqu. The age of radiolaria in the radiolarian chert is Late Jurassic–Cretaceous. The basalt and ultramafic rock of the ophiolite also are overlaid by Tertiary Liuqu conglomerate, which contains numerous pebble components of ophiolite, indicating that the Tethys Ocean began to close at the end of Cretaceous Period. The isotopic data of gabbro, diabase, and albite granite in the Xigaze ophiolite are approximately 126–139 Ma, which indicates that the ophiolite formed in the Early Cretaceous. The K‐Ar age of amphibole in garnet amphibolite in the ophiolite mélange is 81 Ma, indicating that tectonic ophiolite emplacement occurred at the end of Late Cretaceous. Research in petrology, petrological chemistry, mineralogy, and geochemistry of volcanic rocks and dikes of the Xigaze ophiolite indicate the following characteristics: (1) They are mainly composed of basalt, basaltic andesite, dolerite, and diabase and are characterized by high TiO2 (0.7–1.47%), low MgO (mostly less than 8%), and low SiO2 (mostly less than 53%). (2) The volcanic rocks and dikes of the Xigaze ophiolite show light rare earth element (LREE)‐depleted rare earth element (REE) patterns. (3) The spider diagrams of the volcanic rocks and dikes of the Xigaze ophiolite exhibit LILE depletion relative to high‐field‐strength element (HFSE) patterns with left oblique features. (4) No protogenetic olivine and clinoenstatite was detected. (5) Some dikes show low TiO2 and high MgO, in which a few of Cr‐enriched spinels and a very few pseudomorphs of olivine, orthopyroxene can be seen. They show more distinctive affinity as boninitic rock and canbe classified to boninite series rock. The previously mentioned features of the volcanic rocks and dikes in the Xigaze ophiolite implies that these ophiolites formed in a mid‐ocean ridge (MOR) in the earlier stage and than forearc extension of subduction initiation occurred once at the later stage of the evolution of the Xigaze ophiolite. The forearc extention caused further melting of the residue‐depleted mantle, resulting in the formation of melts with lower TiO2 and higher MgO. These melts formed as dikes and intruded into the oceanic crust formed in the earlier stage, resulting in a close association of mid‐ocean ridge basalt and the boninite rock of the Xigaze ophiolite.
Petrology, Geochemistry and Tectonic Significance of the Metamorphic Peridotites from Longmuco–Shuanghu Ophiolitic Melange Belt, Tibet
Authors: Yanwang WU , Cai LI , Chaoming XIE , Ming WANG , Peiyuan HU 
Published: April 2013

Abstract:Taoxinghu metamorphic peridotite is a firstly reported mantle sequence of ophiolite since Longmuco‐Shuanghu‐Lancangjiang suture zone (LSLSZ) was proposed, and it is also an important discovered for ophiolite studying in central Qiangtang. Based on detailed analyses of whole–rock geochemistry of Taoxinghu metamorphic peridotites and contrast to metamorphic peridotites in typical ophiolites worldwide, the paper investigates their petrogenesis and geological implication. The petrologic results show that the protolith of Taoxinghu metamorphic perdotites have the mineral assemblage and texture characteristic of mantle peridotite. Most metamorphic peridotites hav near global abyssal peridotites major elements contents, while the few is similar to SSZ‐type peridotites. They exhibit typically U‐shaped REE patterns, characterized by slight enrichment of LREE and HREE relative to MREE and a low fractionated LREE to HREE segment. Trace elements contents are low and all samples are strong enrichment in Cs, U, Pb, weak enrichment in Ba and depletion in Th, but negative Nb anomalies are only observed in few samples. That suggests Taoxinghu metamorphic peridotites have depletion mantle and suprasubduction affinities. A two‐stage evolution history is considered: Taoxinghu metamorphic peridotites originated as the residue from melting at a ridge with 7%‐20% degree of fraction melting and were subsequently modified by interaction with mafic melt and aqueous fluid within mantle wedge on subducted zone. Combined with previous studies, we preliminarily propose Taoxinghu metamorphic peridotites may be the Products of initial rifting of palo–Tethys, forming at middle Ordivician‐upper Cambrian, and they may be the direct evidences for spreading of palo–Tethys.
Zircon Dating and Geological Implications of Granitic Gneiss in the Metamorphic Zone of Gaoligong Mountains in Western Yunnan, China
Authors: Xiaohong TAN , Bo ZHAO , Xikang LI , Zhangbao XU , Zhen ZHANG 
Published: April 2013

Abstract:The general classification of intermediate‐acid intrusive rocks in the metamorphic zone of Gaoligong Mountains as one of the metamorphic terranes of Proterozoic Gaoligong Mountains is problematic regarding the intrusion stage and age, as well as the subsequent metamorphism and deformation. In this study, we investigated granitic gneiss in the metamorphic zone of Gaoligong Mountains based on the 1:50,000 regional geological survey of Qushi Street (2011–2013) and SHRIMP U‐Pb zircon geochronology. Results showed that the SHRIMP U‐Pb zircon dating of granitic gneiss ranged from 163.5±5.7 Ma to 74.0±2.0 Ma. Thus, the granitic gneiss was grouped into orthometamorphic rocks (metamorphic intrusions). The dating data of granite rocks associated with intense metamorphism and deformation were divided into three groups, 163.5±5.7 to 162.3±3.1 Ma, 132.2–101.0 Ma and 99.4±3.5–74.0±2.0 Ma, which respectively represented three independent geologic events including an important magma intrusion with superimposed metamorphic effects in the late Middle Jurassic, regional dynamic metamorphism and superimposed reformation of fluid action in the early Cretaceous, and dynamic metamorphism dominated by ductile shear and metamorphism starting from the late Cretaceous.
Jurassic Black Shales Facies from Qiangtang Basin (Northern Tibet): Rare Earth and Trace Elements for Paleoceanographic Implications
Authors: Lan CHEN , Haisheng YI , Louis Loung‐Yie TSAI , Guiwen XU , Xuejuan DA , Andrew Tien‐Shun LIN 
Published: April 2013

Abstract:The Biluo Co and Amdo 114 station, northern Tibet, cropping out the Early Toarcian and Middle‐Late Tithonian (Jurassic) organic‐rich black shales, have been a focus to petroleum geologists in discussing their oil‐producing potential. This paper first reports the trace elements and rare earth elements to discuss the paleoenvironments, redox conditions and sedimentary mechanisms of those black shales. Both sections exhibit variation in trace element abundances with concentrations <0.1 ppm to 760 ppm, mostly enriched in V, Cr, Ni, Cu, Zn, Mo, Ba and U. Element ratios of Ni/Co, V/Cr, U/Th and V/(V+Ni) plus U were used to identify redox conditions. The shale‐normalized rare earth element (REE) patterns are characterized by the flat‐shale type with instable Ce anomalies and very weekly positive Eu anomalies. Positive Ceanom values are significant with values varying between −0.064 and 0.029 in Biluo Co, which may be interpreted as release of REE and input of riverine terrestrial matter with rich Ce (resulting in pH change) during the anoxic conditions. In the middle parts of Amdo 114 station, distinct negative Ceanom values are observed (−0.238 to −0.111) and associated surface water warming were interpreted as being related to a major sea level rise. In contrast, the formation of the black shales in the lower and upper part of the studied succession took place during a cooler (Ceanom values >−0.10), lower surface water productivity, and lower sea‐level stage. Thus, we emphasize the role of different factors that control the formation of local and regional black shales. The most important factors are sea‐level fluctuations and increasing productivity.
Sedimentary Evolution of the Qinghai–Tibet Plateau in Cenozoic and its Response to the Uplift of the Plateau
Authors: Kexin ZHANG , Guocan WANG , Yadong XU , Mansheng LUO , Junliang JI , Guoqiao XIAO , An WANG , Bowen SONG , Yinpin LIANG , Shangsong JIANG , Kai CAO , Fenning CHEN , Ruiming CHEN , Yongfeng YANG 
Published: April 2013

Abstract:We have studied the evolution of the tectonic lithofacies paleogeography of Paleocene–Eocene, Oligocene, Miocene, and Pliocene of the Qinghai–Tibet Plateau by compiling data regarding the type, tectonic setting, and lithostratigraphic sequence of 98 remnant basins in the plateau area. Our results can be summarized as follows. (1) The Paleocene to Eocene is characterized by uplift and erosion in the Songpan–Garzê and Gangdisê belts, depression (lakes and pluvial plains) in eastern Tarim, Qaidam, Qiangtang, and Hoh Xil, and the Neo‐Tethys Sea in the western and southern Qinghai–Tibet Plateau. (2) The Oligocene is characterized by uplift in the Gangdisê–Himalaya and Karakorum regions (marked by the absence of sedimentation), fluvial transport (originating eastward and flowing westward) in the Brahmaputra region (marked by the deposition of Dazhuka conglomerate), uplift and erosion in western Kunlun and Songpan‐Garzê, and depression (lakes) in the Tarim, Qaidam, Qiangtang, and Hoh Xil. The Oligocene is further characterized by depressional littoral and neritic basins in southwestern Tarim, with marine facies deposition ceasing at the end of the Oligocene. (3) For the Miocene, a widespread regional unconformity (ca. 23 Ma) in and adjacent to the plateau indicates comprehensive uplift of the plateau. This period is characterized by depressions (lakes) in the Tarim, Qaidam, Xining–Nanzhou, Qiangtang, and Hoh Xil. Lacustrine facies deposition expanded to peak in and adjacent to the plateau ca. 18–13 Ma, and north–south fault basins formed in southern Tibet ca. 13–10 Ma. All of these features indicate that the plateau uplifted to its peak and began to collapse. (4) Uplift and erosion occurred during the Pliocene in most parts of the plateau, except in the Hoh Xil–Qiangtang, Tarim, and Qaidam. The continuous uplift and intensive taphrogeny in the plateau divided the original large basin into small basins, deposition of lacustrine facies decreased considerably, and boulderstone accumulated, indicating a response to the overall uplift of the plateau. Here, we discuss the evolution of tectonic lithofacies paleogeography in Cenozoic and its response to the tectonic uplift of the Qinghai‐Tibet Plateau in relation to the above characteristics. We have recognized five major uplift events, which occurred during 58–53 Ma, 45–30 Ma, 25–20 Ma, 13–7 Ma, and since 5 Ma. The results presented here indicate that the paleogeomorphic configurations of the Qinghai–Tibet Plateau turned over during the late Miocene, with high elevations in the east during the pre‐Miocene switching to high contours in the west at the end of Miocene.
Magnetostratigraphy and Anisotropy of Magnetic Susceptibility of the Lulehe Formation in the Northeastern Qaidam Basin
Authors: Xue KE , Junliang JI , Kexin ZHANG , Xiaohu KOU , Bowen SONG , Chaowen WANG 
Published: April 2013

Abstract:The timing of onset of deposition of the Lulehe Formation is a significant factor in understanding the genesis of the Qaidam basin and the evolution of the Tibetan Plateau. Here, we describe a detailed magnetostratigraphic and magnetic fabric study of the middle and lower parts of the Lulehe Formation. A total of 234 samples were collected from 117 sites throughout a thickness of almost 460 m of fluvial and lacustrine deposits at the Xitieshan section in the northeastern Qaidam basin. Out of these sites, 94 sites yielded well‐defined characteristic remanent magnetization components by stepwise thermal demagnetization and were used to establish the magnetostratigraphy of the studied section. Based on correlation with the geomagnetic polarity timescale, the studied section spans the period from 53.8 Ma to 50.7 Ma. Our results show a three‐fold decrease in sedimentation rates as well as marked change in facies from braided river to delta and shore–shallow lake around 52.6 Ma, which suggests tectonic uplift of the northeastern Qaidam basin margin ridge was rapid at the onset of formation of the Qaidam basin and subsequently weakened after 52.6 Ma. The anisotropy of magnetic susceptibility results indicate that tectonic compression stress had reached the northeastern Tibetan Plateau by the early stages of Indo–Eurasian plate collision and that the direction of stress in the study area was NE–SW. Furthermore, a weakening of tectonic compression stress around 52.6 Ma is consistent with sedimentary records. The age of initial deposition of the Qaidam basin (around 53.8 Ma) was almost synchronous with that of the Qiangtang, Hoh Xil, Xining, and Lanzhou basins, which implies that stress was transferred rapidly through the Tibetan Plateau during or immediately after the onset of Indo–Eurasian collision.
Distance transform: a tool for the study of animal colour patterns
Authors: Taylor Christopher H. , Gilbert Francis , Reader Tom 
Published: April 2013

Summary

The information in animal colour patterns plays a key role in many ecological interactions; quantification would help us to study them, but this is problematic. Comparing patterns using human judgement is subjective and inconsistent. Traditional shape analysis is unsuitable as patterns do not usually contain conserved landmarks. Alternative statistical approaches also have weaknesses, particularly as they are generally based on summary measures that discard most or all of the spatial information in a pattern.

We present a method for quantifying the similarity of a pair of patterns based on the distance transform of a binary image. The method compares the whole pattern, pixel by pixel, while being robust to small spatial variations among images.

We demonstrate the utility of the distance transform method using three ecological examples. We generate a measure of mimetic accuracy between hoverflies (Diptera: Syrphidae) and wasps (Hymenoptera) based on abdominal pattern and show that this correlates strongly with the perception of a model predator (humans). We calculate similarity values within a group of mimetic butterflies and compare this with proposed pairings of Müllerian comimics. Finally, we characterise variation in clypeal badges of a paper wasp (Polistes dominula) and compare this with previous measures of variation.

While our results generally support the findings of existing studies that have used simpler ad hoc methods for measuring differences between patterns, our method is able to detect more subtle variation and hence reveal previously overlooked trends.
A Novel Oxygenated Machine Perfusion System for Preservation of the Liver
Authors: Dirkes Marcel C. , Post Ivo C.J.H. , Heger Michal , van Gulik Thomas M. 
Published: April 2013

AbstractMachine perfusion (MP) is a potential method to increase the donor pool for organ transplantation. However, MP systems for liver grafts remain difficult to use because of organ‐specific demands. Our aim was to test a novel, portable MP system for hypothermic preservation of the liver. A portable, pressure‐regulated, oxygenated MP system designed for kidney preservation was adapted to perfuse liver grafts via the portal vein (PV). Three porcine livers underwent 20 h of hypothermic perfusion using Belzer MP solution. The MP system was assessed for perfusate flow, temperature, venous pressure, and pO2/pCO2 during the preservation period. Biochemical and histological parameters were analyzed to determine postpreservation organ damage. Perfusate flow through the PV increased over time from 157 ± 25 mL/min at start to 177 ± 25 mL/min after 20 h. PV pressure remained stable at 13 ± 1 mm Hg. Perfusate temperature increased from 9.7 ± 0.6°C at the start to 11.0 ± 0.0°C after 20 h. Aspartate aminotransferase and lactate dehydrogenase increased from 281 ± 158 and 308 ± 171 U/L after 1 h to 524 ± 163 and 537 ± 168 U/L after 20 h, respectively. Blood gas analysis showed a stable pO2 of 338 ± 20 mm Hg before perfusion of the liver and 125 ± 14 mm Hg after 1 h perfusion. The pCO2 increased from 15 ± 5 mm Hg after 1 h to 53 ± 4 mm Hg after 20 h. No histological changes were found after 20 h of MP. This study demonstrated the feasibility of a portable MP system for preservation of the liver and showed that continuous perfusion via the PV can be maintained with an oxygen‐driven pump system without notable preservation damage of the organ.
Equine leptospirosis in tropical Northern Queensland
Authors: Wangdi C , Picard J , Tan R , Condon F , Dowling B , Gummow B 
Published: April 2013

ObjectiveDetermine leptospiral serodiversity, serodominant serovars and prevalence in the horse population of Northern Queensland (NQ), Australia, with special focus on the Atherton Tableland and Townsville–Burdekin regions.DesignCross‐sectional survey.MethodsSerum samples from 429 horses originating from 172 horse‐owning properties in NQ were collected at regional horse shows and veterinary clinics. Samples were analysed using a microscopic agglutination test. Owners were interviewed on potential risk factors associated with leptospirosis.ResultsOf the 172 properties that submitted samples, horses from 60 properties (35%, 95% confidence interval (CI) 31–39%) in NQ showed evidence of exposure to one or more serovars of Leptospira at a serum dilution of 1 : 100. The proportion of seropositive properties in the Atherton Tableland and Townsville–Burdekin regions was 25% (95% CI 17–33%) and 36% (95% CI 30–43%), respectively. In total, 81 horses had titres to a single serovar and the remained had titres to two or more serovars. Although 20 serovars representing 17 serogroups were detected, serovar Arborea was serodominant and detected in horses from 29 properties. Geldings were more at risk (odds ratio 3.3) of being seropositive to serovar Arborea. The detection of serovar Arborea‐seropositive horses was strongly associated (P < 0.05) with the average annual rainfall each property received and the presence of pigs and sugarcane fields in the vicinity.ConclusionSerological evidence of leptospirosis in horses in NQ indicates that prevalence is high and horses have been exposed to a wide range of serovars.
In vitro susceptibilities of feline and canine Escherichia coli and Pseudomonas spp. isolates to ticarcillin and ticarcillin–clavulanic acid
Authors: Bennett AB , Martin PA , Gottlieb SA , Govendir M 
Published: April 2013

ObjectivesTo investigate in vitro susceptibilities of canine and feline Escherichia coli and canine Pseudomonas spp. isolates to ticarcillin and ticarcillin–clavulanic acid (T/C).DesignIn vitro susceptibility testing of bacterial isolates collected from infections.MethodsWe tested 148 (83 canine and 65 feline) E. coli and 61 canine Pseudomonas spp. isolates for susceptibility to T/C using both disc diffusion and Epsilometer tests (E‐tests). Additionally, susceptibilities of 96 E. coli and 23 canine Pseudomonas spp. isolates were tested via disc diffusion to ticarcillin alone.ResultsOf the E. coli isolates obtained from canine and feline urine, 92% by disc diffusion and 91% by E‐tests were susceptible to T/C. Of the canine Pseudomonas isolates, 90% by disc diffusion and 82% by E‐tests were susceptible to T/C. Of the Pseudomonas spp. isolates from the canine ear canal or tympanic bullae, 12% of isolates tested via disc diffusion and 23% via E‐tests were found to be resistant to T/C. The 50% minimum inhibitory concentration of T/C for all feline E. coli isolates was significantly lower than that for all canine E. coli isolates (P = 0.0031). The addition of clavulanic acid significantly increased the efficacy of ticarcillin against E. coli (P< 0.0001), but had negligible effect against canine Pseudomonas spp. isolates.ConclusionTicarcillin‐clavulanic acid has reasonable in vitro efficacy against canine and feline E. coli, and canine Pseudomonas spp. isolates. However, decisions to use this drug therapeutically must be made on prudent considerations to minimise selection for bacterial resistance.