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Rayleigh Sound Wave Propagation on a Gallium Single Crystal in a Liquid He3 Bath G
Rayleigh sound wave propagation on a gallium single crystal in a liquid He3 bath G. Bellessa To cite this version: G. Bellessa. Rayleigh sound wave propagation on a gallium single crystal in a liquid He3 bath. Journal de Physique Lettres, Edp sciences, 1975, 36 (5), pp.137-139. 10.1051/jphyslet:01975003605013700. jpa-00231172 HAL Id: jpa-00231172 https://hal.archives-ouvertes.fr/jpa-00231172 Submitted on 1 Jan 1975 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. L-137 RAYLEIGH SOUND WAVE PROPAGATION ON A GALLIUM SINGLE CRYSTAL IN A LIQUID He3 BATH G. BELLESSA Laboratoire de Physique des Solides (*) Université Paris-Sud, Centre d’Orsay, 91405 Orsay, France Résumé. - Nous décrivons l’observation de la propagation d’ondes élastiques de Rayleigh sur un monocristal de gallium. Les fréquences d’études sont comprises entre 40 MHz et 120 MHz et la température d’étude la plus basse est 0,4 K. La vitesse et l’atténuation sont étudiées à des tempéra- tures différentes. L’atténuation des ondes de Rayleigh par le bain d’He3 est aussi étudiée à des tem- pératures et des fréquences différentes. -
Daft Punk Collectible Sales Skyrocket After Breakup: 'I Could've Made
BILLBOARD COUNTRY UPDATE APRIL 13, 2020 | PAGE 4 OF 19 ON THE CHARTS JIM ASKER [email protected] Bulletin SamHunt’s Southside Rules Top Country YOURAlbu DAILYms; BrettENTERTAINMENT Young ‘Catc NEWSh UPDATE’-es Fifth AirplayFEBRUARY 25, 2021 Page 1 of 37 Leader; Travis Denning Makes History INSIDE Daft Punk Collectible Sales Sam Hunt’s second studio full-length, and first in over five years, Southside sales (up 21%) in the tracking week. On Country Airplay, it hops 18-15 (11.9 mil- (MCA Nashville/Universal Music Group Nashville), debutsSkyrocket at No. 1 on Billboard’s lion audience After impressions, Breakup: up 16%). Top Country• Spotify Albums Takes onchart dated April 18. In its first week (ending April 9), it earned$1.3B 46,000 in equivalentDebt album units, including 16,000 in album sales, ac- TRY TO ‘CATCH’ UP WITH YOUNG Brett Youngachieves his fifth consecutive cording• Taylor to Nielsen Swift Music/MRCFiles Data. ‘I Could’veand total Made Country Airplay No.$100,000’ 1 as “Catch” (Big Machine Label Group) ascends SouthsideHer Own marks Lawsuit Hunt’s in second No. 1 on the 2-1, increasing 13% to 36.6 million impressions. chartEscalating and fourth Theme top 10. It follows freshman LP BY STEVE KNOPPER Young’s first of six chart entries, “Sleep With- MontevalloPark, which Battle arrived at the summit in No - out You,” reached No. 2 in December 2016. He vember 2014 and reigned for nine weeks. To date, followed with the multiweek No. 1s “In Case You In the 24 hours following Daft Punk’s breakup Thomas, who figured out how to build the helmets Montevallo• Mumford has andearned Sons’ 3.9 million units, with 1.4 Didn’t Know” (two weeks, June 2017), “Like I Loved millionBen in Lovettalbum sales. -
Ellipticity of Seismic Rayleigh Waves for Subsurface Architectured Ground with Holes
Experimental evidence of auxetic features in seismic metamaterials: Ellipticity of seismic Rayleigh waves for subsurface architectured ground with holes Stéphane Brûlé1, Stefan Enoch2 and Sébastien Guenneau2 1Ménard, Chaponost, France 1, Route du Dôme, 69630 Chaponost 2 Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France 52 Avenue Escadrille Normandie Niemen, 13013 Marseille e-mail address: [email protected] Structured soils with regular meshes of metric size holes implemented in first ten meters of the ground have been theoretically and experimentally tested under seismic disturbance this last decade. Structured soils with rigid inclusions embedded in a substratum have been also recently developed. The influence of these inclusions in the ground can be characterized in different ways: redistribution of energy within the network with focusing effects for seismic metamaterials, wave reflection, frequency filtering, reduction of the amplitude of seismic signal energy, etc. Here we first provide some time-domain analysis of the flat lens effect in conjunction with some form of external cloaking of Rayleigh waves and then we experimentally show the effect of a finite mesh of cylindrical holes on the ellipticity of the surface Rayleigh waves at the level of the Earth’s surface. Orbital diagrams in time domain are drawn for the surface particle’s velocity in vertical (x, z) and horizontal (x, y) planes. These results enable us to observe that the mesh of holes locally creates a tilt of the axes of the ellipse and changes the direction of particle movement. Interestingly, changes of Rayleigh waves ellipticity can be interpreted as changes of an effective Poisson ratio. -
Effect of Fabric Anisotropy on the Dynamic Mechanical Behavior Of
EFFECT OF FABRIC ANISOTROPY ON THE DYNAMIC MECHANICAL BEHAVIOR OF GRANULAR MATERIALS by Bo Li Submitted in partial fulfillment of the requirements For the degree of Doctor of Philosophy Dissertation Advisor: Prof. Xiangwu Zeng Department of Civil Engineering Case Western Reserve University January, 2011 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the thesis/dissertation of Bo Li Candidate for Ph. D. degree*. (signed) Xiangwu Zeng Chair of Commitee Adel Saada Wojbor A. Woyczynski Xiong Yu (date) 11/15/2010 *We also certify that written approval has been obtained for any proprietary material contained therein Table of Contents Table of Contents I List of Tables IV List of Figures VI Acknowledgement XI Abstract XII Notation XIV Chapter 1 Introduction ........................................................................................ 1 1.1 Effect of Anisotropy on Granular Materials ........................................................................... 1 1.2 Research Objectives ............................................................................................................... 1 1.3 Outline of the Dissertation ...................................................................................................... 2 1.4 Review of the Effect of Fabric Anisotropy on Clay ............................................................... 3 1.4.1 Experimental Study on Effect of Fabric Anisotropy on Clay ......................................... 3 1.4.2 Analytical Method on Effect of Fabric Anisotropy -
Confidential Manuscript Submitted to Engineering Geology
Confidential manuscript submitted to Engineering Geology 1 Landslide monitoring using seismic refraction tomography – The 2 importance of incorporating topographic variations 3 J S Whiteley1,2, J E Chambers1, S Uhlemann1,3, J Boyd1,4, M O Cimpoiasu1,5, J L 4 Holmes1,6, C M Inauen1, A Watlet1, L R Hawley-Sibbett1,5, C Sujitapan2, R T Swift1,7 5 and J M Kendall2 6 1 British Geological Survey, Environmental Science Centre, Nicker Hill, Keyworth, 7 Nottingham, NG12 5GG, United Kingdom. 2 School of Earth Sciences, University 8 of Bristol, Wills Memorial Building, Queens Road, Bristol, BS8 1RJ, United 9 Kingdom. 3 Lawrence Berkeley National Laboratory (LBNL), Earth and 10 Environmental Sciences Area, 1 Cyclotron Road, Berkeley, CA 94720, United 11 States of America. 4 Lancaster Environment Center (LEC), Lancaster University, 12 Lancaster, LA1 4YQ, United Kingdom 5 Division of Agriculture and Environmental 13 Science, School of Bioscience, University of Nottingham, Sutton Bonington, 14 Leicestershire, LE12 5RD, United Kingdom 6 Queen’s University Belfast, School of 15 Natural and Built Environment, Stranmillis Road, Belfast, BT9 5AG, United 16 Kingdom 7 University of Liege, Applied Geophysics, Department ArGEnCo, 17 Engineering Faculty, B52, 4000 Liege, Belgium 18 19 Corresponding author: Jim Whiteley ([email protected]) 20 21 Copyright British Geological Survey © UKRI 2020/ University of Bristol 2020 22 1 Confidential manuscript submitted to Engineering Geology 23 Abstract 24 Seismic refraction tomography provides images of the elastic properties of 25 subsurface materials in landslide settings. Seismic velocities are sensitive to 26 changes in moisture content, which is a triggering factor in the initiation of many 27 landslides. -
STRUCTURE of EARTH S-Wave Shadow P-Wave Shadow P-Wave
STRUCTURE OF EARTH Earthquake Focus P-wave P-wave shadow shadow S-wave shadow P waves = Primary waves = Pressure waves S waves = Secondary waves = Shear waves (Don't penetrate liquids) CRUST < 50-70 km thick MANTLE = 2900 km thick OUTER CORE (Liquid) = 3200 km thick INNER CORE (Solid) = 1300 km radius. STRUCTURE OF EARTH Low Velocity Crust Zone Whole Mantle Convection Lithosphere Upper Mantle Transition Zone Layered Mantle Convection Lower Mantle S-wave P-wave CRUST : Conrad discontinuity = upper / lower crust boundary Mohorovicic discontinuity = base of Continental Crust (35-50 km continents; 6-8 km oceans) MANTLE: Lithosphere = Rigid Mantle < 100 km depth Asthenosphere = Plastic Mantle > 150 km depth Low Velocity Zone = Partially Melted, 100-150 km depth Upper Mantle < 410 km Transition Zone = 400-600 km --> Velocity increases rapidly Lower Mantle = 600 - 2900 km Outer Core (Liquid) 2900-5100 km Inner Core (Solid) 5100-6400 km Center = 6400 km UPPER MANTLE AND MAGMA GENERATION A. Composition of Earth Density of the Bulk Earth (Uncompressed) = 5.45 gm/cm3 Densities of Common Rocks: Granite = 2.55 gm/cm3 Peridotite, Eclogite = 3.2 to 3.4 gm/cm3 Basalt = 2.85 gm/cm3 Density of the CORE (estimated) = 7.2 gm/cm3 Fe-metal = 8.0 gm/cm3, Ni-metal = 8.5 gm/cm3 EARTH must contain a mix of Rock and Metal . Stony meteorites Remains of broken planets Planetary Interior Rock=Stony Meteorites ÒChondritesÓ = Olivine, Pyroxene, Metal (Fe-Ni) Metal = Fe-Ni Meteorites Core density = 7.2 gm/cm3 -- Too Light for Pure Fe-Ni Light elements = O2 (FeO) or S (FeS) B. -
2021 Oregon Seismic Hazard Database: Purpose and Methods
State of Oregon Oregon Department of Geology and Mineral Industries Brad Avy, State Geologist DIGITAL DATA SERIES 2021 OREGON SEISMIC HAZARD DATABASE: PURPOSE AND METHODS By Ian P. Madin1, Jon J. Francyzk1, John M. Bauer2, and Carlie J.M. Azzopardi1 2021 1Oregon Department of Geology and Mineral Industries, 800 NE Oregon Street, Suite 965, Portland, OR 97232 2Principal, Bauer GIS Solutions, Portland, OR 97229 2021 Oregon Seismic Hazard Database: Purpose and Methods DISCLAIMER This product is for informational purposes and may not have been prepared for or be suitable for legal, engineering, or surveying purposes. Users of this information should review or consult the primary data and information sources to ascertain the usability of the information. This publication cannot substitute for site-specific investigations by qualified practitioners. Site-specific data may give results that differ from the results shown in the publication. WHAT’S IN THIS PUBLICATION? The Oregon Seismic Hazard Database, release 1 (OSHD-1.0), is the first comprehensive collection of seismic hazard data for Oregon. This publication consists of a geodatabase containing coseismic geohazard maps and quantitative ground shaking and ground deformation maps; a report describing the methods used to prepare the geodatabase, and map plates showing 1) the highest level of shaking (peak ground velocity) expected to occur with a 2% chance in the next 50 years, equivalent to the most severe shaking likely to occur once in 2,475 years; 2) median shaking levels expected from a suite of 30 magnitude 9 Cascadia subduction zone earthquake simulations; and 3) the probability of experiencing shaking of Modified Mercalli Intensity VII, which is the nominal threshold for structural damage to buildings. -
The Growing Wealth of Aseismic Deformation Data: What's a Modeler to Model?
The Growing Wealth of Aseismic Deformation Data: What's a Modeler to Model? Evelyn Roeloffs U.S. Geological Survey Earthquake Hazards Team Vancouver, WA Topics • Pre-earthquake deformation-rate changes – Some credible examples • High-resolution crustal deformation observations – borehole strain – fluid pressure data • Aseismic processes linking mainshocks to aftershocks • Observations possibly related to dynamic triggering The Scientific Method • The “hypothesis-testing” stage is a bottleneck for earthquake research because data are hard to obtain • Modeling has a role in the hypothesis-building stage http://www.indiana.edu/~geol116/ Modeling needs to lead data collection • Compared to acquiring high resolution deformation data in the near field of large earthquakes, modeling is fast and inexpensive • So modeling should perhaps get ahead of reproducing observations • Or modeling could look harder at observations that are significant but controversial, and could explore a wider range of hypotheses Earthquakes can happen without detectable pre- earthquake changes e.g.Parkfield M6 2004 Deformation-Rate Changes before the Mw 6.6 Chuetsu earthquake, 23 October 2004 Ogata, JGR 2007 • Intraplate thrust earthquake, depth 11 km • GPS-detected rate changes about 3 years earlier – Moment of pre-slip approximately Mw 6.0 (1 div=1 cm) – deviations mostly in direction of coseismic displacement – not all consistent with pre-slip on the rupture plane Great Subduction Earthquakes with Evidence for Pre-Earthquake Aseismic Deformation-Rate Changes • Chile 1960, Mw9.2 – 20-30 m of slow interplate slip over a rupture zone 920+/-100 km long, starting 20 minutes prior to mainshock [Kanamori & Cipar (1974); Kanamori & Anderson (1975); Cifuentes & Silver (1989) ] – 33-hour foreshock sequence north of the mainshock, propagating toward the mainshock hypocenter at 86 km day-1 (Cifuentes, 1989) • Alaska 1964, Mw9.2 • Cascadia 1700, M9 Microfossils => Sea level rise before1964 Alaska M9.2 • 0.12± 0.13 m sea level rise at 4 sites between 1952 and 1964 Hamilton et al. -
Bray 2011 Pseudostatic Slope Stability Procedure Paper
Paper No. Theme Lecture 1 PSEUDOSTATIC SLOPE STABILITY PROCEDURE Jonathan D. BRAY 1 and Thaleia TRAVASAROU2 ABSTRACT Pseudostatic slope stability procedures can be employed in a straightforward manner, and thus, their use in engineering practice is appealing. The magnitude of the seismic coefficient that is applied to the potential sliding mass to represent the destabilizing effect of the earthquake shaking is a critical component of the procedure. It is often selected based on precedence, regulatory design guidance, and engineering judgment. However, the selection of the design value of the seismic coefficient employed in pseudostatic slope stability analysis should be based on the seismic hazard and the amount of seismic displacement that constitutes satisfactory performance for the project. The seismic coefficient should have a rational basis that depends on the seismic hazard and the allowable amount of calculated seismically induced permanent displacement. The recommended pseudostatic slope stability procedure requires that the engineer develops the project-specific allowable level of seismic displacement. The site- dependent seismic demand is characterized by the 5% damped elastic design spectral acceleration at the degraded period of the potential sliding mass as well as other key parameters. The level of uncertainty in the estimates of the seismic demand and displacement can be handled through the use of different percentile estimates of these values. Thus, the engineer can properly incorporate the amount of seismic displacement judged to be allowable and the seismic hazard at the site in the selection of the seismic coefficient. Keywords: Dam; Earthquake; Permanent Displacements; Reliability; Seismic Slope Stability INTRODUCTION Pseudostatic slope stability procedures are often used in engineering practice to evaluate the seismic performance of earth structures and natural slopes. -
Living on Shaky Ground: How to Survive Earthquakes and Tsunamis
HOW TO SURVIVE EARTHQUAKES AND TSUNAMIS IN OREGON DAMAGE IN doWNTOWN KLAMATH FALLS FRom A MAGNITUde 6.0 EARTHQUAke IN 1993 TSUNAMI DAMAGE IN SEASIde FRom THE 1964GR EAT ALASKAN EARTHQUAke 1 Oregon Emergency Management Copyright 2009, Humboldt Earthquake Education Center at Humboldt State University. Adapted and reproduced with permission by Oregon Emergency You Can Prepare for the Management with help from the Oregon Department of Geology and Mineral Industries. Reproduction by permission only. Next Quake or Tsunami Disclaimer This document is intended to promote earthquake and tsunami readiness. It is based on the best SOME PEOplE THINK it is not worth preparing for an earthquake or a tsunami currently available scientific, engineering, and sociological because whether you survive or not is up to chance. NOT SO! Most Oregon research. Following its suggestions, however, does not guarantee the safety of an individual or of a structure. buildings will survive even a large earthquake, and so will you, especially if you follow the simple guidelines in this handbook and start preparing today. Prepared by the Humboldt Earthquake Education Center and the Redwood Coast Tsunami Work Group (RCTWG), If you know how to recognize the warning signs of a tsunami and understand in cooperation with the California Earthquake Authority what to do, you will survive that too—but you need to know what to do ahead (CEA), California Emergency Management Agency (Cal EMA), Federal Emergency Management Agency (FEMA), of time! California Geological Survey (CGS), Department of This handbook will help you prepare for earthquakes and tsunamis in Oregon. Interior United States Geological Survey (USGS), the National Oceanographic and Atmospheric Administration It explains how you can prepare for, survive, and recover from them. -
Seismic Wavefield Imaging of Earth's Interior Across Scales
TECHNICAL REVIEWS Seismic wavefield imaging of Earth’s interior across scales Jeroen Tromp Abstract | Seismic full- waveform inversion (FWI) for imaging Earth’s interior was introduced in the late 1970s. Its ultimate goal is to use all of the information in a seismogram to understand the structure and dynamics of Earth, such as hydrocarbon reservoirs, the nature of hotspots and the forces behind plate motions and earthquakes. Thanks to developments in high- performance computing and advances in modern numerical methods in the past 10 years, 3D FWI has become feasible for a wide range of applications and is currently used across nine orders of magnitude in frequency and wavelength. A typical FWI workflow includes selecting seismic sources and a starting model, conducting forward simulations, calculating and evaluating the misfit, and optimizing the simulated model until the observed and modelled seismograms converge on a single model. This method has revealed Pleistocene ice scrapes beneath a gas cloud in the Valhall oil field, overthrusted Iberian crust in the western Pyrenees mountains, deep slabs in subduction zones throughout the world and the shape of the African superplume. The increased use of multi- parameter inversions, improved computational and algorithmic efficiency , and the inclusion of Bayesian statistics in the optimization process all stand to substantially improve FWI, overcoming current computational or data- quality constraints. In this Technical Review, FWI methods and applications in controlled- source and earthquake seismology are discussed, followed by a perspective on the future of FWI, which will ultimately result in increased insight into the physics and chemistry of Earth’s interior. -
Earthquake Measurements
EARTHQUAKE MEASUREMENTS The vibrations produced by earthquakes are detected, recorded, and measured by instruments call seismographs1. The zig-zag line made by a seismograph, called a "seismogram," reflects the changing intensity of the vibrations by responding to the motion of the ground surface beneath the instrument. From the data expressed in seismograms, scientists can determine the time, the epicenter, the focal depth, and the type of faulting of an earthquake and can estimate how much energy was released. Seismograph/Seismometer Earthquake recording instrument, seismograph has a base that sets firmly in the ground, and a heavy weight that hangs free2. When an earthquake causes the ground to shake, the base of the seismograph shakes too, but the hanging weight does not. Instead the spring or string that it is hanging from absorbs all the movement. The difference in position between the shaking part of the seismograph and the motionless part is Seismograph what is recorded. Measuring Size of Earthquakes The size of an earthquake depends on the size of the fault and the amount of slip on the fault, but that’s not something scientists can simply measure with a measuring tape since faults are many kilometers deep beneath the earth’s surface. They use the seismogram recordings made on the seismographs at the surface of the earth to determine how large the earthquake was. A short wiggly line that doesn’t wiggle very much means a small earthquake, and a long wiggly line that wiggles a lot means a large earthquake2. The length of the wiggle depends on the size of the fault, and the size of the wiggle depends on the amount of slip.