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1.
<正>The present paper is devoted to an overview on fossil Coleoptera studied from Inner Mongolia, Daohugou(Middle Jurassic,Jiulongshan Formation)and Liaoning(Upper Jurassic-Lower Cretaceous,Yixian Formation)deposited in Chinese collections.As a result,species of the tribe Sperchopsini and Hydrophilini from Hydrophilidae,families and subfamilies Silphidae,Syndesinae from Lucanidae,Pleocomidae,Trogidae, Trogissitidae,Pyrochroidae,Diaperinae from Tenebrionidae,and Cerambycidae were first registered in the Mesozoic and some families were defined as new.It was shown that many superfamilies represented in the Recent Fauna were formed within the Middle Jurassic and Lower Cretaceous.The materials examined confirm the hypothesis that Cucujiformian beetles are a younger group than other infraordera of Polyphaga(Staphyliniformia and Elateriformia)and,therefore,they appeared in the fossil record only in the late Mesozoic.It was shown and confirmed that most superfamilies appeared in the fossil records before Cucujoidea.The synonymy of Notocupes Ponomarenko,1964;Sinocupes Lin,1976,syn.nov.;Amblomma Tan,Ren et Liu 2005,syn.nov.;Euryomma Tan, Ren et Shih,2006,syn.nov.,non Stein,1899 and Ovatocupes Tan et Ren,2006,syn.nov.;synonymy of Tetraphalerus Waterhouse,1901 and Odontomma Tan,Ren et Ge 2006,syn.nov.;and synonymy of Priacmopsis Ponomarenko,1966 and Latocupes Tan et Ren,2006,syn.nov.are proposed.Sinorhombocoleus papposus Tan et Ren,2009 is transferred from the family Rhombocoleidae to Schizophoridae.Cervicatinius complanus Tan,Ren et Shih,2007 and Forticatinius elegans Tan,Ren et Shih,2007 are transferred from the family Catiniidae(suborder Archostemata)to superfamily Cleroidea(suborder Polyphaga:first among the family Peltidae and second as a closely related group to the latter family).The family Parandrexidae is transferred from the superfamily Cucujoidea to Cleroidea.The ecological circumstances of the past ecosystems and hypotheses of historical development of the order Coleoptera are discussed.The age of faunas examined is considered.The list of the taxa described from Daohugou and Liaoning is compiled.  相似文献   

2.
The fossil snakefly family Baissopteridae from the Lower Cretaceous (upper Barremian) of the Yixian Formation of Liaoning Province, China is reviewed. Two genera and five species of Baissopteridae are recorded, including a new genus, namely Microbaissoptera gen. nov., and three new species, i.e., Baissoptera bicolor sp. nov., Baissoptera sinica sp. nov., and Microbaissoptera monosticha sp. nov. Moreover, Baissoptera euneura Ren, 1997 is herein treated as a new junior synonymy of Baissoptera grandis Ren in Ren et al., 1995. Baissoptera minima Ponomarenko, 1993 is transferred to the presently described new genus Microbaissoptera gen. nov. based on the small body-size and the presence of a single gradate series of crossveins in radial and medial areas of posterior part of both fore- and hind wings. A key to genera of Baissopteridae is provided.  相似文献   

3.
重大地质灾害应急实践表明, 应急监测是重要处置措施之一。由于缺乏地质灾害事件应急防治研究, 目前对应急监测、应急预警的认识尚不统一、实践中与一般监测、预警和预报相混淆, 也没有可供借鉴的方案。以地质灾害应急处置实践为基础, 通过情景分析、构建和归纳, 提出应急监测是指突发地质灾害灾情险情发生后, 紧急采取的灾害地质体及风险因子监测措施, 包括临灾和灾后2类基本情景。与非应急工况比较, 通过应急适应性分析, 初步提出了其应急监测技术条件, 并给出了单体滑坡和单沟石流灾害应急监测预警方案, 包括目标任务、监测内容、网点设计、监测方法和预警判据等。以期有益于突发地质灾害应急防治管理和现场决策。  相似文献   

4.
Beetles belonging to the extinct tribe Notocupedini (Coleoptera: Cupedidae: Ommatinae) are widespread in Mesozoic deposits of eastern Pangaea. Four new species are proposed in the genus/collective group Zygadenia: Z. liui sp. nov. (Aptian: Yixian Formation, China), Z. martinae sp. nov. (Sinemurian–Toarcian: Cattamarra Coal Measures, Australia), Z. floodpagei sp. nov. and Z. simpsoni sp. nov. (Hauterivian–Barremian: Weald Clay Group, UK). The Purbeck species Z. tuberculata and Z. angliae are figured from the Weald Clay Group for the first time. It is also proposed that Notocupes, the largest genus in this presumably xylophagous, warm climate tribe, be divided into two subgenera: Notocupes subgen. n. and Amblomma stat. nov. In addition, the palaeoecological significance of colour markings in these Mesozoic beetles is also discussed for the first time. These discoveries extend the geographic distribution/stratigraphic range of Zygadenia and shed new light on the palaeoecology and diversity of so-called 'primitive' beetles in pre-angiospermous woodlands.  相似文献   

5.
A new and simple method is proposed to obtain estimates of recovery functions: the Bi-Gaussian approach. Existing methods estimate recovery functions with conditional distributions where the conditioning set is all the data available. Here instead the simple kriging estimate of the Gaussian transform is proposed to be used. Results in the point recovery case are identical to the multi-Gaussian approach of Verly (1983, 1984), whereas in the non-point-support situation, an approximation is derived which saves computer time as compared to employing the strict multi-Gaussian hypothesis. Two examples compare favorably with the well-established disjunctive kriging method (discrete Gaussian model).  相似文献   

6.
寒武纪年代地层的研究现状和研究方向   总被引:9,自引:6,他引:3  
全球寒武系的底、顶界层型已被确定 ,但寒武系内的统和阶一级的全球标准划分尚待进行。介绍了国际地层委员会寒武系分会有关建阶的意见和推荐的 13个分阶的层位 ;同时介绍了劳亚大陆新近提出的 4统 6阶的年代地层划分方案。回顾了我国的建阶过程 ,指出我国现有的阶一级单位实质上仍然是岩石地层单位 ,具有建立在单位层型上、底界被粗略界定因而时间意义不明确、对比性差、与岩石地层单位重名和不利于竞争国际标准阶和GSSPs等一系列缺点。在湘西、黔东地区新建的 5个阶可取代我国现有的中—晚寒武世年代地层系统。建议暂将我国寒武系划分为 3统和 9个阶 ,即 :下寒武统梅树村阶、筇竹寺阶、沧浪铺阶和龙王庙阶 ;中寒武统台江阶和王村阶 ;上寒武统酉水阶、瓦儿岗阶和桃源阶。  相似文献   

7.
A simplified framework is proposed for evaluating the probability of “serviceability failure” in a braced excavation in a spatially random field. Here, the “serviceability failure” is said to occur when the excavation-induced wall or ground movement exceeds specified limiting values. Knowledge of this probability can aid in engineering decision-making to prevent damage to adjacent infrastructures. The proposed framework consists of five elements: (1) finite element method (FEM) for analyzing wall and ground responses in a braced excavation, (2) fuzzy set modeling of parameter uncertainty, (3) spatial averaging technique for handling spatial variability, (4) vertex method for processing fuzzy input through FEM model, and (5) interpretation of fuzzy output. The proposed framework is demonstrated through a well-documented case history. The results show the proposed framework is simple and effective for assessing the probability of serviceability failure in a braced excavation in a spatially random field. To focus on the proposed fuzzy FEM approach, the scope of this paper is limited to one-dimensional modeling of spatial variability with an assumed exponential autocorrelation function.  相似文献   

8.
FERRY  J. M. 《Journal of Petrology》1986,27(3):695-714
Wood & Graham (1986) suggest that fluid: rock ratios ofFerry (1984) were over-estimated because the temperature ofthe biotite isograd, inferred from biotite-garnet and calcite-dolomitegeothermometry, was underestimated by {small tilde}40?C. Wood& Graham's critique of calcite-dolomite geothermometry isincomplete because it fails to account for the effect of MnCO3substitutions in calcite on estimated temperatures. New datathat consider the effects of both FeCO3 and MnCO3 substitutionssuggest that published calcite-dolomite temperatures need nosignificant correction. Their proposed correction to biotite-garnettemperatures, based on the garnet solid solution model of Ganguly& Saxena (1984), has an uncertainty of at least 100 percent and is not significantly different from zero. An empiricalscheme that corrects for the effects of grossular and spessartinesubstitution in garnet on estimated temperature, along withthe large uncertainty in Wood and Graham's proposed correction,suggest that published biotite-garnet temperatures also needno significant revision. The preferred temperature for the biotiteisograd remains {small tilde}400?C. In turn, the preferred estimatesof fluid: rock ratios remain unchanged; pelitic phyllites interactedwith at least 1-2 rock volumes fluid during the biotite-formingreaction at 400?C. Varied geologic, petrologic, and isotopic data are reviewedthat support fluid:rock ratios > 1 during low-grade metamorphismboth in south-central Maine and worldwide. Chemical interactionbetween rocks and fluids that are initially out of equilibriummay be an essential driving force behind many instances of low-graderegional metamorphism. Fluid:rock ratios > 1 and recent stableisotope studies should encourage serious consideration of amulti-pass model for metamorphic fluid flow.  相似文献   

9.
文中阐述了Bohacs、Carroll等提出的陆相湖泊充填类型的划分理论,总结了陆相湖泊沉积的3种典型沉积组合:河流 湖泊相组合、波动深湖相组合和蒸发相组合,并对应各自的组合方式划分出3种湖泊充填模式:过充填湖泊、平衡充填湖泊和欠充填湖泊。笔者通过对中国松辽盆地中、晚白垩世时期泉头组-嫩江组的湖泊沉积相组合、层序地层特征等资料进行总结,并与Bohacs提出的湖泊填充模式划分进行对比,初步建立起松辽盆地当时的湖泊充填模式,进而对松辽盆地当时烃源岩埋藏和分布进行了分析和总结。  相似文献   

10.
A universal particle velocity based algorithm for simulating hydraulic fractures, previously proposed for Newtonian fluids, is extended to the class of shear-thinning fluids. The scheme is not limited to any particular elasticity operator or crack propagation regime. The computations are based on two dependent variables: the crack opening and the reduced particle velocity. The application of the latter facilitates utilization of the local condition of Stefan type (speed equation) to trace the fracture front. The condition is given in a general explicit form which relates the crack propagation speed (and the crack length) to the solution tip asymptotics. The utilization of a modular structure, and the adaptive character of its basic blocks, result in a flexible numerical scheme. The computational accuracy of the proposed algorithm is validated against a number of analytical benchmark solutions.  相似文献   

11.
A new terminology is proposed for categorising values in geological reference materials based on the confidence that may be placed in an individual datum. This classification scheme is designed to be applicable to data derived from both cooperative analysis programmes and compilations of data published in the literature. Use of the following terminology is proposed: "certified value equivalent", "recommended value" and "provisional value", depending on the associated one sigma confidence limits and other analytical criteria listed in Table 1. To demonstrate the application to data that was originally assessed using different criteria and terminology, the proposed scheme has been used to reclassify data derived from the cooperative analysis program for USGS SDO-1 (Devonian Shale) and a compilation of published data for USGS G-1 (granite).  相似文献   

12.
Details on the preparation of a Laterite Standard Reference Material (SRM) from Venezuela, on the homogeneity-testing and the round-robin testing scheme from 11 international laboratories are given. The proposed values (%) for the concentrations of the main constituents are: Al2O3: 37.38, SiO2: 1.16, TiO2: 3.15, Fe2O3: 35.77 and LOI, 22.44. The following statistical parameters are also reported: the arithmetic mean, the variance, the standard deviation, the coefficient of variation, the median, the skewness factor, the preferred mean, the geometric mean, the Gastwirth Median and the dominant cluster mode.  相似文献   

13.
Water losses risk assessment: an example from Carpathian karst   总被引:1,自引:1,他引:0  
The multipurpose dam and reservoir “Bogovina” in the Crni Timok valley is one of several projects that have been initiated to improve water availability in Serbia. The site and height of the dam were initially proposed without consideration of risk factors such as water leakage or stability of the banks. Later, complex hydrogeological and speleological surveys and tests identified the potential of significant water losses from the reservoir area connected mainly to the karstic aquifer, and the nearby Bogovina cave system. The analyses show that once the reservoir is filled up, groundwater flow currently oriented towards the future reservoir would saturate the upper part of the karstified rocks, reactivate currently unsaturated pathways and form a reverse discharge outside of the reservoir area. In response to these findings, the dam design and technical details have been adapted accordingly: the dam height has been reduced by 9 m, and it is proposed that grouting and consolidation work be conducted both at the foundation of the dam and extensively on the embankments. It was concluded that although the proposed remedial measures cannot guarantee reservoir tightness, they can reduce the risk of large-scale leaking.  相似文献   

14.
In his recent paper on surge mark formation and morphology, Bull (1978) has provided considerable new and interesting information on these peculiar features. Of particular note is his observation that the laminae within surge marks are continuous and not dissected as would be expected if the surge marks were erosional rills: the previously proposed mechanism of formation (High & Picard, 1968; Picard & High, 1973). Consequently, it becomes necessary to formulate an alternative explanation for surge mark origin, and Bull (1978, p. 885) offers the suggestion that: ‘Surge marks may be the result of selective depositional/erosional processes together with external deformation pressures.’  相似文献   

15.
The International Stratigraphic Chart of the Phanerozoic is constructed by drawing lower boundaries of stratigraphic units with reference to Global Boundary Stratotype Section and Point. Some systems retain former, usually European, names of stages, whereas new sequences of stages are proposed for others, such as for Cambrian and Ordovician. The boundaries of 64 stages of 100 had been approved by the beginning of 2014. Fifty-three of these boundaries were drawn with regard to biostratigraphic criteria; one ichnological, six magnetostratigraphic, two chemo stratigraphic, one impact, and one climatic criteria. Their type sections are distributed over continents as follows: thirty-nine in Europe, twelve in Asia, nine in North America, and four in Africa. They are located in 19 countries: ten in China, nine in the United Kingdom, nine in Italy, seven in the United States, six in France, five in Spain, three in Czech, two in Morocco, two in Sweden, and one in each of several more countries. Although none is in Russia, candidates are proposed for stages of the Cambrian, Carboniferous, Permian, Triassic, and Jurassic Systems. Type sections for the Sakmarian and Artinskian have already been agreed. With the present work speed, it will take two or three decades to complete the scale construction. The General Stratigraphic Scale of Russia and the International Chart gradually converge. Their similarity at the stage level is 84%. Major disagreements exist only in the Cambrian and Permian Systems.  相似文献   

16.
Nearly ten years have elapsed since Korzhinskii proposed his basis of paragenetic analysis in 1957. During this period the method was developed and popularised by including diverse problems of physico-chemical petrology and the study of mineralisation. In the process, definite progress has been made in solving theoretical and practical problems. The present review does not pretend to be a full discussion of research in this field: its aim is reassessment of the most important achievements in certain problems of metamorphism, granitic and syenitic magmatism, metasomatism and formation of ores.  相似文献   

17.
微生物沉积作用在前寒武纪地层中普遍发育,在显生宙的一些地层中也较为发育。在碳酸盐岩地层之中,以叠层石为代表的微生物岩尤为引人注目。经过长期研究,2000年Riding曾经将微生物碳酸盐岩分为叠层石、凝块石、树形石和均一石4大类型。实际上,核形石以其较为广泛的发育和特殊的微组构也应该作为一种典型的微生物碳酸盐岩类型而纳入微生物碳酸盐岩的分类体系之中,而不能简单地作为球状叠层石。而那些纹理石灰岩,较厚的纹理和较深的产出沉积环境与叠层石形成明显的区别,也应该作为一种微生物碳酸盐岩的类型。生物沉积作用所形成的碳酸盐岩,以生物礁岩最为典型,在20世纪70年代曾经被Embry和Kloven归为骨架岩、障积岩、粘结岩三大类型,后来又增加了胶结岩,这是对20世纪50年代Folk、Dunham关于灰岩成因结构分类体系的良好补充。这些生物礁岩石以其高能量形成环境而有时又几乎见不到颗粒而与"颗粒含量越高沉积环境的能量越高"的基本理念不相符,所以Wright在1992年将它们归为生物作用类岩石,从而将灰岩划分为沉积作用、生物作用、成岩作用三大类。根据该分类,Folk和Dunham所描述的分类则属于沉积作用类灰岩,而Embry和Kloven所描述的生物礁岩石则归为生物作用类灰岩。微生物碳酸盐岩,总体上构成生物作用类碳酸盐岩中的粘结岩类,以其明显的微生物作用特点而具有自己的分类体系;它不但作为生物礁岩石的主要类型,而且也常常以生物礁、生物层和生物丘三种形式发育在地层之中。因此,上述概念和认识的进步,在强调微生物沉积作用的重要性的同时,有必要将微生物碳酸盐岩重新分为6大类:叠层石、凝块石、核形石、树形石、纹理石和均一石。  相似文献   

18.
Review of the Permian Camptoneuritidae (Insecta:Grylloblattida)   总被引:1,自引:1,他引:0  
<正>The Permian family Camptoneuritidae(Insecta:Grylloblattida)is reviewed.New synonymies are proposed:Camptoneuritidae Martynov,1930=Demopteridae Carpenter,1950,syn.nov.,=Jabloniidae Kukalova, 1964,syn.nov.Key to genera of Camptoneuritidae is given.All genera are redescribed and illustrated. Camptoneurites soyanensis sp.nov.from Soyana locality(Middle Permian,Kazanian Stage;Arkhangelsk Region, Russia)and Tyulkinia bashkuevi gen.et sp.nov.from Tyulkino locality(Lower Permian,Kungurian Stage;Perm Region,Russia)are described.  相似文献   

19.
Size of a debris flow deposition: model experiment approach   总被引:5,自引:0,他引:5  
 The prediction of the dangerous extent of a debris flow deposition is of vital importance, but difficult to achieve. Precise prediction of the depositional boundary of a debris flow event is impossible, but the size of a debris flow deposition could provide some estimates of the area, length, width, and thickness of a debris flow deposition. Based on in situ depositional experiments performed on a debris flow creek just after debris flows, a rule of thumb expressed by a group of equations containing the multiple-variate nonlinear functions is proposed in this paper. The interrelationships between the size and the causation also are discussed, and some empirical formulae to calculate the causative parameters for different regions are presented. Received: 24 April 1995 · Accepted: 21 June 1995  相似文献   

20.
Within the definition given by UNESCO of World Cultural and Natural Heritage, geoheritage finds its significance both as the geological or geomorphological elements of nature worthy of conservation and as habitat of threatened species of outstanding universal value from the point of view of science or conservation. Definitions, methods, and applications for the conservation and valorization of geoheritage have been proposed for various types of environments, but their application in underwater areas is seldom, if even, reported. In this study, we propose a set of definitions and methods for the evaluation of scientific and additional values in underwater environment, and we apply them in two Mediterranean areas: Sigri (Greece, Lesvos Island) and Bergeggi (Italy, Liguria region). Results show the applicability of the schemes proposed in different geological and geomorphological settings and provide tools for the evaluation of abiotic underwater heritage in the two areas.  相似文献   

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