arXiv: Geophysics最新文献_第10页

Improving predictive power of physically based rainfall-induced shallow landslide models: a probabilistic approach 提高基于降雨诱发的浅层滑坡模型的预测能力:一种概率方法

arXiv: Geophysics Pub Date : 2013-05-21 DOI: 10.5194/gmdd-6-1367-2013

S. Raía, M. Alvioli, M. Rossi, R. Baum, J. Godt, F. Guzzetti

{"title":"Improving predictive power of physically based rainfall-induced shallow landslide models: a probabilistic approach","authors":"S. Raía, M. Alvioli, M. Rossi, R. Baum, J. Godt, F. Guzzetti","doi":"10.5194/gmdd-6-1367-2013","DOIUrl":"https://doi.org/10.5194/gmdd-6-1367-2013","url":null,"abstract":"Distributed models to forecast the spatial and temporal occurrence of rainfall-induced shallow landslides are based on deterministic laws. These models extend spatially the static stability models adopted in geotechnical engineering, and adopt an infinite-slope geometry to balance the resisting and the driving forces acting on the sliding mass. An infiltration model is used to determine how rainfall changes pore-water conditions, modulating the local stability/instability conditions. A problem with the operation of the existing models lays in the difficulty in obtaining accurate values for the several variables that describe the material properties of the slopes. The problem is particularly severe when the models are applied over large areas, for which sufficient information on the geotechnical and hydrological conditions of the slopes is not generally available. To help solve the problem, we propose a probabilistic Monte Carlo approach to the distributed modeling of rainfall-induced shallow landslides. For the purpose, we have modified the Transient Rainfall Infiltration and Grid-Based Regional Slope-Stability Analysis (TRIGRS) code. The new code (TRIGRS-P) adopts a probabilistic approach to compute, on a cell-by-cell basis, transient pore-pressure changes and related changes in the factor of safety due to rainfall infiltration. Infiltration is modeled using analytical solutions of partial differential equations describing one-dimensional vertical flow in isotropic, homogeneous materials. Both saturated and unsaturated soil conditions can be considered. TRIGRS-P copes with the natural variability inherent to the mechanical and hydrological properties of the slope materials by allowing values of the TRIGRS model input parameters to be sampled randomly from a given probability distribution. [..]","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114154204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 136

Strong Ground Motion in the 2011 Tohoku Earthquake: a 1Directional - 3Component Modeling 2011年东北地震的强地面运动:一个单向-三分量模拟

arXiv: Geophysics Pub Date : 2013-05-01 DOI: 10.1785/0120120208

M. P. S. d’Avila, J. Semblat, L. Lenti

{"title":"Strong Ground Motion in the 2011 Tohoku Earthquake: a 1Directional - 3Component Modeling","authors":"M. P. S. d’Avila, J. Semblat, L. Lenti","doi":"10.1785/0120120208","DOIUrl":"https://doi.org/10.1785/0120120208","url":null,"abstract":"Local wave amplification due to strong seismic motions in surficial multilayered soil is influenced by several parameters such as the wavefield polarization and the dynamic properties and impedance contrast between soil layers. The present research aims at investigating seismic motion amplification in the 2011 Tohoku earthquake through a one-directional three-component (1D-3C) wave propagation model. A 3D nonlinear constitutive relation for dry soils under cyclic loading is implemented in a quadratic line finite element model. The soil rheology is modeled by mean of a multi-surface cyclic plasticity model of the Masing-Prandtl-Ishlinskii-Iwan (MPII) type. Its major advantage is that the rheology is characterized by few commonly measured parameters. Ground motions are computed at the surface of soil profiles in the Tohoku area (Japan) by propagating 3C signals recorded at rock outcrops, during the 2011 Tohoku earthquake. Computed surface ground motions are compared to the Tohoku earthquake records at alluvial sites and the reliability of the 1D-3C model is corroborated. The 1D-3C approach is compared with the combination of three separate one-directional analyses of one motion component propagated independently (1D-1C approach). The 3D loading path due to the 3C-polarization leads to multiaxial stress interaction that reduces soil strength and increases nonlinear effects. Time histories and spectral amplitudes, for the Tohoku earthquake, are numerically reproduced. The 1D-3C approach allows the evaluation of various parameters of the 3C motion and 3D stress and strain evolution all over the soil profile.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115522241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 15

Seismic modeling using the frozen Gaussian approximation 使用冻结高斯近似的地震建模

arXiv: Geophysics Pub Date : 2013-04-12 DOI: 10.1190/SEGAM2013-1225.1

Xu Yang, Jianfeng Lu, Sergey Fomel

引用次数: 9

The influence of changes in water content on the electrical resistivity of a natural unsaturated loess 含水量变化对天然非饱和黄土电阻率的影响

arXiv: Geophysics Pub Date : 2013-03-21 DOI: 10.1520/GTJ103587

Jos'e Munoz-Castelblanco, Jean-Michel Pereira, P. Delage, Yu-Jun Cui

引用次数: 49

Exact solution of Terzaghi's consolidation equation and extension to two/three-dimensional cases (3th versione) Terzaghi固结方程的精确解及其在二维/三维情况下的推广(第3版)

arXiv: Geophysics Pub Date : 2013-01-02 DOI: 10.4236/am.2013.44099

R. D. Francesco

引用次数: 8

On the FP7 BlackSeaHazNet Project and Its Possible Application for Harmonic Existence of the Regions FP7 BlackSeaHazNet项目及其在区域谐波存在性中的可能应用

arXiv: Geophysics Pub Date : 2012-12-11 DOI: 10.1007/978-94-007-6152-0_22

S. Mavrodiev, L. Pekevski

引用次数: 0

The Chandler wobble and Solar day 钱德勒摆动和太阳日

arXiv: Geophysics Pub Date : 2012-10-27 DOI: 10.48550/arXiv.1210.7376

D. Kiryan, G. Kiryan

引用次数: 0

Characteristic earthquake model, 1884 -- 2011, R.I.P 特征地震模型，1884—2011，安息吧

arXiv: Geophysics Pub Date : 2012-07-20 DOI: 10.1785/0220120107

Y. Kagan, D. Jackson, R. Geller

{"title":"Characteristic earthquake model, 1884 -- 2011, R.I.P","authors":"Y. Kagan, D. Jackson, R. Geller","doi":"10.1785/0220120107","DOIUrl":"https://doi.org/10.1785/0220120107","url":null,"abstract":"Unfortunately, working scientists sometimes reflexively continue to use \"buzz phrases\" grounded in once prevalent paradigms that have been subsequently refuted. This can impede both earthquake research and hazard mitigation. Well-worn seismological buzz phrases include \"earthquake cycle,\" \"seismic cycle,\" \"seismic gap,\" and \"characteristic earthquake.\" They all assume that there are sequences of earthquakes that are nearly identical except for the times of their occurrence. If so, the complex process of earthquake occurrence could be reduced to a description of one \"characteristic\" earthquake plus the times of the others in the sequence. A common additional assumption is that characteristic earthquakes dominate the displacement on fault or plate boundary \"segments.\" The \"seismic gap\" (or the effectively equivalent \"seismic cycle\") model depends entirely on the \"characteristic\" assumption, with the added assumption that characteristic earthquakes are quasi-periodic. However, since the 1990s numerous statistical tests have failed to support characteristic earthquake and seismic gap models, and the 2004 Sumatra earthquake and 2011 Tohoku earthquake both ripped through several supposed segment boundaries. Earthquake scientists should scrap ideas that have been rejected by objective testing or are too vague to be testable.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"242 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132062545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 86

The variability of tidewater-glacier calving: origin of event-size and interval distributions 潮汐-冰川崩解的变率:事件大小和间隔分布的起源

arXiv: Geophysics Pub Date : 2012-05-08 DOI: 10.3189/2014JoG13J215

A. Chapuis, T. Tetzlaff

{"title":"The variability of tidewater-glacier calving: origin of event-size and interval distributions","authors":"A. Chapuis, T. Tetzlaff","doi":"10.3189/2014JoG13J215","DOIUrl":"https://doi.org/10.3189/2014JoG13J215","url":null,"abstract":"Calving activity at the termini of tidewater glaciers produces a wide range of iceberg sizes at irregular intervals. We present calving-event data obtained from continuous observations of the termini of two tidewater glaciers on Svalbard, and show that the distributions of event sizes and inter-event intervals can be reproduced by a simple calving model focusing on the mutual interplay between calving and the destabilization of the glacier terminus. The event-size distributions of both the field and the model data extend over several orders of magnitude and resemble power laws. The distributions of inter-event intervals are broad, but have a less pronounced tail. In the model, the width of the size distribution increases with the calving susceptibility of the glacier terminus, a parameter measuring the effect of calving on the stress in the local neighborhood of the calving region. Inter-event interval distributions, in contrast, are insensitive to the calving susceptibility. Above a critical susceptibility, small perturbations of the glacier result in ongoing self-sustained calving activity. The model suggests that the shape of the event-size distribution of a glacier is informative about its proximity to this transition point. Observations of rapid glacier retreats can be explained by supercritical self-sustained calving.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"196 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133084831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 38

A recent tipping point in the Arctic sea-ice cover: abrupt and persistent increase in the seasonal cycle since 2007 北极海冰覆盖的一个最近的临界点:自2007年以来，季节性周期的突然和持续增加

arXiv: Geophysics Pub Date : 2012-04-24 DOI: 10.5194/TC-7-275-2013

V. Livina, T. Lenton

{"title":"A recent tipping point in the Arctic sea-ice cover: abrupt and persistent increase in the seasonal cycle since 2007","authors":"V. Livina, T. Lenton","doi":"10.5194/TC-7-275-2013","DOIUrl":"https://doi.org/10.5194/TC-7-275-2013","url":null,"abstract":"There is ongoing debate over whether Arctic sea-ice has already passed a `tipping point', or whether it will do so in the future. Several recent studies argue that the loss of summer sea ice does not involve an irreversible bifurcation, because it is highly reversible in models. However, a broader definition of a `tipping point' also includes other abrupt, non-linear changes that are neither bifurcations nor necessarily irreversible. Examination of satellite data for Arctic sea-ice area reveals an abrupt increase in the amplitude of seasonal variability in 2007 that has persisted since then. We identified this abrupt transition using recently developed methods that can detect multi-modality in time-series data and sometimes forewarn of bifurcations. When removing the mean seasonal cycle (up to 2008) from the satellite data, the residual sea-ice fluctuations switch from uni-modal to multi-modal behaviour around 2007. We originally interpreted this as a bifurcation in which a new lower ice cover attractor appears in deseasonalised fluctuations and is sampled in every summer-autumn from 2007 onwards. However, this interpretation is clearly sensitive to how the seasonal cycle is removed from the raw data, and to the presence of continental land masses restricting winter-spring ice fluctuations. Furthermore, there was no robust early warning signal of critical slowing down prior to the hypothesized bifurcation. Early warning indicators do however show destabilization of the summer-autumn sea-ice cover since 2007. Thus, the bifurcation hypothesis lacks consistent support, but there was an abrupt and persistent increase in the amplitude of the seasonal cycle of Arctic sea-ice cover in 2007, which we describe as a (non-bifurcation) `tipping point'. Our statistical methods detect this `tipping point' and its time of onset.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132965635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 45