arXiv: Geophysics最新文献_第4页

Topological properties of epidemic aftershock processes 流行病余震过程的拓扑性质

arXiv: Geophysics Pub Date : 2019-08-09 DOI: 10.1002/essoar.10501014.1

Jordi Baró Urbea

{"title":"Topological properties of epidemic aftershock processes","authors":"Jordi Baró Urbea","doi":"10.1002/essoar.10501014.1","DOIUrl":"https://doi.org/10.1002/essoar.10501014.1","url":null,"abstract":"Earthquakes in seismological catalogs and acoustic emission events in lab experiments can be statistically described as a linear Hawkes point process, where the spatio-temporal rate of events is a linear superposition of background intensity and the aftershock clusters triggered by preceding activity. Traditionally, statistical seismology has interpreted this model as the outcome of an epidemic branching process, where one-to-one causal links can be established between mainshocks and aftershocks. Declustering techniques have been used to infer the underlying triggering trees and relate their topological properties with epidemic branching models. Here, we review how the standard Epidemic Type Aftershock Sequence (ETAS) model extends from the Galton-Watson (GW) branching processes and bridges two extreme cases: Poisson sampling and scale-free power-law trees. We report the most essential topological properties expected in GW epidemic trees: the branching probability, the distribution of tree size, the expected family size, and the relation between average leaf-depth and tree size. We find that such topological properties depend exclusively on two sampling parameters of the standard ETAS model: the average branching ratio $N_b$ and the exponent ratio $alpha/b$ determining the branching probability distribution. From these results, one can use the memory-less GW as a null-model for empirical triggering processes and assess the validity of the ETAS model to reproduce the statistics of natural and artificial catalogs.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116263688","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: 3

Full reciprocity-gap waveform inversion enabling sparse-source acquisition 全往复式间隙波形反演实现稀疏源采集

arXiv: Geophysics Pub Date : 2019-07-22 DOI: 10.1190/GEO2019-0527.1

F. Faucher, G. Alessandrini, H. Barucq, M. V. de Hoop, Romina Gaburro, E. Sincich

{"title":"Full reciprocity-gap waveform inversion enabling sparse-source acquisition","authors":"F. Faucher, G. Alessandrini, H. Barucq, M. V. de Hoop, Romina Gaburro, E. Sincich","doi":"10.1190/GEO2019-0527.1","DOIUrl":"https://doi.org/10.1190/GEO2019-0527.1","url":null,"abstract":"We perform quantitative sub-surface Earth-imaging by setting up the Full Reciprocity-gap Waveform Inversion (FRgWI ) method. The reconstruction relies on iterative minimization of a misfit functional which is specifically designed for data obtained from dual-sensors devices. In addition to the pressure field, the dual-sensors devices are able to measure the normal velocity of the waves and have been deployed in exploration geophysics. The use of reciprocity-based misfit functional provides additional features compared to the more traditional least-squares approaches with, in particular, that the observational and computational acquisitions can be different. Therefore, the source positions and wavelets that generate the measurements are not needed for the reconstruction procedure and, in fact, the numerical acquisition (for the simulations) can be arbitrarily chosen. We illustrate our method with three-dimensional experiments, where we first show that the reciprocity-gap inversion behaves better than the Full Waveform Inversion (FWI) in the same context. Next, we investigate arbitrary numerical acquisitions in two ways: firstly, when few measurements are given, we use a dense numerical acquisition (compared to the observational one). On the other hand, with a dense observational acquisition, we employ a sparse computational acquisition, with multiple-point sources, to reduce the numerical cost. We highlight that the reciprocity-gap functional is very efficient in both situations and is much more robust with respect to cross-talk than shot-stacking.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121307975","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: 13

The topological origin of anomalous transport: Persistence of β in the face of varying correlation length. 异常输运的拓扑起源:β在面对不同的相关长度时的持续性。

arXiv: Geophysics Pub Date : 2019-06-17 DOI: 10.5194/egusphere-egu2020-7871

Y. Edery

{"title":"The topological origin of anomalous transport: Persistence of β in the face of varying correlation length.","authors":"Y. Edery","doi":"10.5194/egusphere-egu2020-7871","DOIUrl":"https://doi.org/10.5194/egusphere-egu2020-7871","url":null,"abstract":"\u0000 Traditional concepts for flow in porous media assume that the heterogenous distribution of hydraulic conductivity is the source for the contaminant temporal and spatial heavy tail, a process known as anomalous or non-Fickian transport; this anomalous transport behavior can be captured by the β parameter in the continues time random walk (CTRW) framework. In previous studies we showed that there is a functional form relating the β parameter to the permeability variance1 and fracture alignment in fracture fields2. Moreover, we showed that this variance is strongly influencing the reaction pattern during transport3.  This study shows that as the spatial correlation length, between these heterogenous distribution of hydraulic conductivities, increase, the anomaly of the flow reduces, yet the β value is unchanged suggesting that there is a topological component to the flow field, captured by the β4. This finding is verified by an analysis on the flow field, showing that the changes in the conductivity values have little effect on the flow field morphology, which points to the topological component in the flow.<ol><li>Y. Edery, A. Guadagnini, H. Scher and B. Berkowitz, Water Resources Research 50 (2), 1490-1505 (2014).</li>\u0000<li>Y. Edery, S. Geiger and B. Berkowitz, Water Resources Research 52 (7), 5634-5643 (2016).</li>\u0000<li>Y. Edery, G. M. Porta, A. Guadagnini, H. Scher and B. Berkowitz, Transport in Porous Media 115 (2), 291-310 (2016).</li>\u0000<li>Y. Edery, arXiv preprint arXiv:1906.07061 (2019).</li>\u0000</ol>\u0000","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131006130","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: 1

Correlation of ground motion duration with its intensity metrics: A simulation based approach 地震动持续时间与其强度指标的相关性:基于模拟的方法

arXiv: Geophysics Pub Date : 2019-05-07 DOI: 10.22115/SCCE.2020.227576.1207

Mojtaba Harati, M. Mashayekhi, H. Estekanchi

引用次数: 6

Nonisothermal effects on water potential measurement in a simple geometry 简单几何中水势测量的非等温效应

arXiv: Geophysics Pub Date : 2019-02-12 DOI: 10.1103/PHYSREVFLUIDS.6.023801

P. Lidon, E. Perrot, A. Stroock

{"title":"Nonisothermal effects on water potential measurement in a simple geometry","authors":"P. Lidon, E. Perrot, A. Stroock","doi":"10.1103/PHYSREVFLUIDS.6.023801","DOIUrl":"https://doi.org/10.1103/PHYSREVFLUIDS.6.023801","url":null,"abstract":"In this paper, we investigate quantitatively the coupling between gradients of temperature and of chemical or water potential under steady state conditions in the vapor phase. This coupling is important for the measurement and modeling of the dynamics of water in unsaturated environments like soils and plants. We focus on a simple non-equilibrium scenario in which a gradient of temperature exists across an air-filled gap that separates two aqueous phases with no net transfer of water. This scenario is relevant for measurements of the water potential in environmental and industrial contexts. We use a new tool, a microtensiometer, to perform these measurements. We observed variations of water potential with difference of temperature across the air gap of $-SI{7.9(3)}{megapascalperkelvin}$, in agreement with previous measurements. Our result is close to a first order theoretical prediction, highlighting that most of the effect comes from the variation of saturation pressure with temperature. We then show that thermodiffusion and natural convection could occur in our experiment and discuss how these effects could explain the small discrepancy observed between measurements and first order theoretical prediction.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133076266","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: 1

Mapping groundwater potential zones in Cilongok Area, Banyumas, Central Java using 2D geoelectrical resistivity 利用二维地电阻率在中爪哇Banyumas的Cilongok地区绘制地下水潜在带

arXiv: Geophysics Pub Date : 2018-12-04 DOI: 10.31227/osf.io/mbyq7

S. Herho, Plato Martuani Siregar, Iqbal Syarief, Dasapta Erwin Irawan, Marlison Justiana Sinaga

{"title":"Mapping groundwater potential zones in Cilongok Area, Banyumas, Central Java using 2D geoelectrical resistivity","authors":"S. Herho, Plato Martuani Siregar, Iqbal Syarief, Dasapta Erwin Irawan, Marlison Justiana Sinaga","doi":"10.31227/osf.io/mbyq7","DOIUrl":"https://doi.org/10.31227/osf.io/mbyq7","url":null,"abstract":"The aim of this study is to investigate the presence of potential aquifer layers that would be used as a source of clean water for residents in Cilongok sub-district. We conducted a ground water potential survey at two locations in the sub-district, i.e. Cikidang and Kalisari villages. At each location, geoelectric measurements were taken with the Wenner configuration and the horizontal distance of 900 meters, so that we can get the estimation of lithology layers that potentially store groundwater up to the depth of $pm 100$ meters. Then the measurement result was processed by using Res2DInv software to get the 2D resistivity images of rock layers. Based on the resistivity estimation and observation of regional geological conditions in that area, then we conducted 2D interpretation about potential lithology layers that economically potential for water well drilling and to be utilized as a source of clean water for the residents. Based on the interpretation of lithology, it was known that the aquifer layer that has the potential as a source of clean water is a layer that consists of coarse and porous tuffs from volcanic eruption products that can easily drain groundwater on the average about 28 to 45 meters depth in Cikidang village and about 45 to 60 meters depth in Kalisari village.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130806735","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: 0

Slow-Slip Phenomena Represented by the One-Dimensional Burridge-Knopoff Model of Earthquakes 一维Burridge-Knopoff模型所代表的慢滑现象

arXiv: Geophysics Pub Date : 2018-04-18 DOI: 10.7566/JPSJ.87.053001

H. Kawamura, Maho Yamamoto, Y. Ueda

引用次数: 3

Comparative Assessment of Soil-Structure Interaction Regulations of ASCE 7-16 and ASCE 7-10 ASCE 7-16与ASCE 7-10土-结构相互作用规律对比评价

arXiv: Geophysics Pub Date : 2018-04-17 DOI: 10.1061/9780784481325.040

F. Khosravikia, M. Mahsuli, M. Ghannad

{"title":"Comparative Assessment of Soil-Structure Interaction Regulations of ASCE 7-16 and ASCE 7-10","authors":"F. Khosravikia, M. Mahsuli, M. Ghannad","doi":"10.1061/9780784481325.040","DOIUrl":"https://doi.org/10.1061/9780784481325.040","url":null,"abstract":"This paper evaluates the consequences of practicing soil structure interaction (SSI) regulations of ASCE 7-16 on seismic performance of building structures. The motivation for this research stems from the significant changes in the new SSI provisions of ASCE 7-16 compared to the previous 2010 edition. Generally, ASCE 7 considers SSI as a beneficial effect, and allows designer to reduce the design base shear. However, literature shows that this idea cannot properly capture the SSI effects on nonlinear systems. ASCE 7-16 is the first edition of ASCE 7 that considers the SSI effect on yielding systems. This study investigates the consequences of practicing the new provisions on a wide range of buildings with different dynamic characteristics on different soil types. Ductility demand of the structure forms the performance metric of this study, and the probability that practicing SSI provisions, in lieu of fixed-base provisions, increases the ductility demand of the structure is computed. The analyses are conducted within a probabilistic framework which considers the uncertainties in the ground motion and in the properties of the soil-structure system. It is concluded that, for structures with surface foundation on moderate to soft soils, SSI regulations of both ASCE 7-10 and ASCE 7-16 are fairly likely to result in a similar and larger structural responses than those obtained by practicing the fixed-base design regulations. However, for squat and ordinary stiff structures on soft soil or structures with embedded foundation on moderate to soft soils, the SSI provisions of ASCE 7-16 result in performance levels that are closer to those obtained by practicing the fixed-base regulations. Finally, for structures on very soft soils, the new SSI provisions of ASCE 7-16 are likely to rather conservative designs.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127703679","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: 5

Storage and Dissipation of Energy in Prabhakar Viscoelasticity Prabhakar粘弹性中能量的储存和耗散

arXiv: Geophysics Pub Date : 2017-12-12 DOI: 10.3390/math6020015

Ivano Colombaro, A. Giusti, S. Vitali

引用次数: 23

Virtual plane-wave imaging via Marchenko redatuming 通过马尔琴科重新记录的虚拟平面波成像

arXiv: Geophysics Pub Date : 2017-11-30 DOI: 10.1093/gji/ggy143

G. Meles, K. Wapenaar, J. Thorbecke

引用次数: 19