The Northern Giudicarie and the Meran-Mauls fault (Alps,Northern Italy) in the light of new paleomagnetic and geochronological data from boudinaged Eo-/Oligocene tonalites     

Hannah Pomella  Urs Klötzli  Robert Scholger  Michael Stipp  Bernhard Fügenschuh 《International Journal of Earth Sciences》2011,100(8):1827-1850

This study concentrates on small intrusions along two important faults of the Giudicarie fault system, the Northern Giudicarie and the Meran-Mauls fault, summarised under the term tonalitic lamellae. Magnetic fabric analyses in combination with structural field data indicate dextral strike slip deformation along the NE–SW striking northern part of the Giudicarie fault system, the Meran-Mauls fault, overprinted by younger thrusting. The regional stressfield was oriented approximately NNW–SSE during Tertiary times. The distinctive change in deformation along the Meran-Mauls fault from dextral strike slip to top-SE thrusting may be caused by a rotation or bending of the fault after the intrusion of the tonalites and the formation of their horizontal magnetic foliation. Based on the assumption of a preliminary straight Periadriatic lineament bent by the NNW-wards advancement of the Southalpine indenter, the tonalitic lamellae may be interpreted as lenses sheared off from the Adamello batholith during indentation. New U/Pb data on zircon show that some of the lamellae are of Oligocene (Rupelian), others of Late Eocene (Priabonian) age. An amphibole-gabbro lens occurring on the Meran-Mauls fault provides a Middle Eocene (Bartonian) age. Among the major Periadriatic plutons, only the southern units of the Adamello batholith also intruded in the Eocene that suggests a strong correlation between the tonalitic lamellae and the Adamello batholith. The analyses of the remanent magnetisation and the Curie point determinations argue for magnetite as the main carrier of a viscous magnetisation blocked at relatively low temperatures. This indicates slow cooling of the investigated intrusions along the Giudicarie fault system down to approximately 300°C, which is in contrast to the fast cooling determined for the Adamello intrusion units currently at the surface. The new zircon fission track data also show later cooling of the tonalites along the Giudicarie fault system when compared with the Adamello batholith in the south and the Mauls lamellae in the north, indicating that this area contains magmatic bodies exhumed from a deeper structural level than in the Adamello and the Mauls region. This may be due to important top-SE thrusting and transpressive faulting in the footwall of the Northern Giudicarie fault and the Meran-Mauls fault.  相似文献   

Listric versus planar normal fault geometry: an example from the Eisenstadt-Sopron Basin (E Austria)   总被引：1，自引：0，他引：1  

Darko Spahić  Ulrike Exner  Michael Behm  Bernhard Grasemann  Alexander Haring  Herbert Pretsch 《International Journal of Earth Sciences》2011,100(7):1685-1695

In a gravel pit at the eastern margin of the Eisenstadt-Sopron Basin, a satellite of Vienna Basin (Austria), Neogene sediments are exposed in the hanging wall of a major normal fault. The anticlinal structure and associated conjugated secondary normal faults were previously interpreted as a rollover anticline above a listric normal fault. The spatial orientation and distribution of sedimentary horizons and crosscutting faults were mapped in detail on a laser scan of the outcrop wall. Subsequently, in order to assess the 3D distribution and geometry of this fault system, a series of parallel ground penetrating radar (GPR) profiles were recorded behind the outcrop wall. Both outcrop and GPR data were compiled in a 3D structural model, providing the basis for a kinematic reconstruction of the fault plane using balanced cross-section techniques. However, the kinematic reconstruction results in a geologically meaningless normal fault cutting down- and up-section. Additionally, no evidence for a weak layer serving as ductile detachment horizon (i.e. salt or clay horizon) can be identified in stratigraphic profiles. Instead, the observed deflection of stratigraphic horizons may be caused by a displacement gradient along a planar master fault, with a maximum displacement in the fault centre, decreasing towards the fault tips. Accordingly, the observed deflection of markers in the hanging wall—and in a nearby location in the footwall of the normal fault—is interpreted as large-scale fault drag along a planar fault that records a displacement gradient, instead of a rollover anticline related to a listric fault.  相似文献   

Synthetic Spectra for Carbon Stars from Dynamica Model Atmospheres     

Rita Loidl  Josef Hron  Bernhard Aringer  Susanne Höfner  Uffe G. Jφrgensen 《Astrophysics and Space Science》1997,255(1-2):289-290

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Bernhard Butzin 《GeoJournal》1991,2(1):11-26

Within a typical process of urbanization several particularities can be noticed in the Helsinki region: The peninsular location does not allow a zonal expansion of the city. It has rather enforced a tight spatial sectoral expansion with specific problems of traffic and land use. The retarded industrialization has led to an unusually fast population increase without control until the 1960s.The rapid growth created a twofold problem: pressure of population versus inadequate housing, small residences versus high rents; consequently selective migration and small size families. The number of jobs rapidly increased and displaced the residential population of the inner city. This resulted in high traffic which neither the few main roads nor the public transport system of central Helsinki could cope with.These problems correspond to the essential tasks of urban planning: the bottle neck in housing construction has to be broken; the growth of jobs in the central city needs to be stopped as well as the displacement of the residential population. Decentralization, especially of the private tertiary and quartary sector may help. A system of central places within the region would diminish the commuting traffic. Transportation may be solved by a concept of growth points and growth axis along the railway lines.This grown concept of Helsinki should be thought over under the now foreseeable conditions of population stagnation.  相似文献   

XFEM,strong discontinuities and second-order work in shear band modeling of saturated porous media     

Ehsan Mikaeili  Bernhard Schrefler 《Acta Geotechnica》2018,13(6):1249-1264

We investigate shear band initiation and propagation in fully saturated porous media by means of a combination of strong discontinuities (discontinuities in the displacement field) and XFEM. As a constitutive behavior of the solid phase, a Drucker–Prager model is used within a framework of non-associated plasticity to account for dilation of the sample. Strong discontinuities circumvent the difficulties which appear when trying to model shear band formation in the context of classical nonlinear continuum mechanics and when trying to resolve them with classical numerical methods like the finite element method. XFEM, on the other hand, is well suited to deal with problems where a discontinuity propagates, without the need of remeshing. The numerical results are confirmed by the application of Hill’s second-order work criterion which allows to evaluate the material point instability not only locally but also for the whole domain.  相似文献   

Enhancing adaptive composite map projections: Wagner transformation between the Lambert azimuthal and the transverse cylindrical equal-area projections   总被引：1，自引：0，他引：1  

Bernhard Jenny  Bojan Šavrič 《制图学和地理信息科学》2018,45(5):456-463

The adaptive composite map projection technique changes the projection to minimize distortion for the geographic area shown on a map. This article improves the transition between the Lambert azimuthal projection and the transverse equal-area cylindrical projection that are used by adaptive composite projections for portrait-format maps. Originally, a transverse Albers conic projection was suggested for transforming between these two projections, resulting in graticules that are not symmetric relative to the central meridian. We propose the alternative transverse Wagner transformation between the two projections and provide equations and parameters for the transition. The suggested technique results in a graticule that is symmetric relative to the central meridian, and a map transformation that is visually continuous with changing map scale.  相似文献   

Impact of an 0.2 km3 Rock Avalanche on Lake Eibsee (Bavarian Alps,Germany) – Part I: Reconstruction of the paleolake and Effects of the Impact     

Sibylle Knapp  Philipp Mamot  Bernhard Lempe  Michael Krautblatter 《地球表面变化过程与地形》2021,46(1):296-306

Rock avalanches destroy and reshape landscapes in only a few minutes and are among the most hazardous processes on Earth. The surface morphology of rock avalanche deposits and the interaction with the underlying material are crucial for runout properties and reach. Water within the travel path is displaced, producing large impact waves and reducing friction, leading to long runouts. We hypothesize that the 0.2 km³ Holocene Eibsee rock avalanche from Mount Zugspitze in the Bavarian Alps overran and destroyed Paleolake Eibsee and left a unique sedimentological legacy of processes active during the landslide. We captured 9.5 km of electrical resistivity tomography (ERT) profiles across the rock avalanche deposits, with up to 120 m penetration depth and more than 34 000 datum points. The ERT profiles reveal up to ~50 m thick landslide debris, locally covering up to ~30 m of rock debris with entrained fine-grained sediments on top of isolated remnants of decametre-wide paleolake sediments. The ERT profiles allow us to infer processes involved in the interaction of the rock avalanche with bedrock, lake sediments, and morainal sediments, including shearing, bulging, and bulldozing. Complementary data from drilling, a gravel pit exposure, laboratory tests, and geomorphic features were used for ERT calibration. Sediments overrun by the rock avalanche show water-escape structures. Based on all of these datasets, we reconstructed both position and size of the paleolake prior to the catastrophic event. Our reconstruction of the event contributes to process an understanding of the rock avalanche and future modelling and hazard assessment. Here we show how integrated geomorphic, geophysical, and sedimentological approaches can provide detailed insights into the impact of a rock avalanche on a lake. © 2020 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd  相似文献   

Brixenbach research catchment: Quantification of runoff process proportions in a small Alpine catchment depending on soil moisture states and precipitation characteristics     

Gertraud Meißl  Clemens Geitner  Andreas Batliner  Klaus Klebinder  Bernhard Kohl  Gerhard Markart 《水文研究》2021,35(6):e14186

The Brixenbach valley is a small Alpine torrent catchment (9.2 km², 820–1950 m a.s.l., 47.45°, 12.26°) in Tyrol, Austria. Intensive hydrological research in the catchment since more than 12 years, including a hydrogeological survey, pedological and land use mapping, measurements of precipitation, runoff, soil moisture and infiltration as well as the conduction of rainfall simulations, has contributed to understand the hydrological response of the catchment, its subcatchments and specific sites. The paper presents a synthesis of the research in form of runoff process maps for different soil moisture states and precipitation characteristics, derived with the aid of a newly developed Soil-hydrological model. These maps clearly visualize the differing runoff reaction of different subcatchments. The pasture dominated areas produce high surface flow rates during short precipitation events (1 h, 86 mm) with high rainfall intensity, whilst the forested areas often develop shallow subsurface flow. Dry preconditions lead to a slight reduction of surface flow, long rainfall events (24 h, 170 mm) to a dominance of deep subsurface flow and percolation.  相似文献   

A compromise aspect-adaptive cylindrical projection for world maps     

Bernhard Jenny  Bojan Šavrič  Tom Patterson 《International journal of geographical information science》2013,27(6):935-952

There are two problems with current cylindrical projections for world maps. First, existing cylindrical map projections have a static height-to-width aspect ratio and do not automatically adjust their aspect ratio in order to optimally use available canvas space. Second, many of the commonly used cylindrical compromise projections show areas and shapes at higher latitudes with considerable distortion. This article introduces a new compromise cylindrical map projection that adjusts the distribution of parallels to the aspect ratio of a canvas. The goal of designing this projection was to show land masses at central latitudes with a visually balanced appearance similar to how they appear on a globe. The projection was constructed using a visual design procedure where a series of graphically optimized projections was defined for a select number of aspect ratios. The visually designed projections were approximated by polynomial expressions that define a cylindrical projection for any height-to-width ratio between 0.3:1 and 1:1. The resulting equations for converting spherical to Cartesian coordinates require a small number of coefficients and are fast to execute. The presented aspect-adaptive cylindrical projection is well suited for digital maps embedded in web pages with responsive web design, as well as GIS applications where the size of the map canvas is unknown a priori. We highlight the projection with a height-to-width ratio of 0.6:1, which we call the Compact Miller projection because it is inspired by the Miller Cylindrical projection. Unlike the Miller Cylindrical projection, the Compact Miller projection has a smaller height-to-width ratio and shows the world with less areal distortion at higher latitudes. A user study with 448 participants verified that the Compact Miller – together with the Plate Carrée projection – is the most preferred cylindrical compromise projection.  相似文献   

煤系有机质多阶段成气的分子碳同位素表征及其对高过成熟干酪根生气潜力评价的启示     

孙永革  杨中威  Bernhard CRAMER 《地球化学》2013,42(2)

采用开放体系在线程序升温裂解-色谱-碳同位素比值质谱技术(PY/GC-IRMS)考察了煤系有机质热演化过程中甲烷瞬时生成速率与碳同位素组成特征,提出煤系有机质不同热演化进程甲烷生成的四个阶段:生油窗阶段、主生气阶段、晚期生气阶段(芳环侧链断裂)、开环-缩聚作用阶段.以一级反应动力学为基础,采用高斯分布算法,计算了各阶段甲烷产出的动力学参数.研究结果对煤成气资源量的正确评价,特别是近年来有机质高演化阶段成气潜力的评价具有重要指示意义.  相似文献