This document discusses seismic waves and velocities. It provides information on P waves and S waves, including their dependence on density and elastic properties of materials. Tables show measured seismic velocities for different rock types. Empirical relationships are described between velocity, density, and depth, such as Birch's law and the Nafe-Drake curve. Factors that affect P wave and S wave velocities are listed, such as mineral content, pressure, temperature, and presence of fluids.
- Simple harmonic motion describes oscillatory or back-and-forth motion caused by a restoring force proportional to displacement from equilibrium.
- Examples of objects that exhibit simple harmonic motion include springs, pendulums, and waves.
- The period and frequency of oscillation depend on attributes like the spring constant, length, or mass in the case of springs and pendulums.
The document discusses generating ephemerides for asteroids using analytical propagation methods. It begins by introducing the objectives, various coordinate systems, and complexities in determining orbital motion. It then covers the equations of motion for two-body motion and conic orbits. The document describes how to generate ephemerides using analytical techniques by calculating orbital element transformations between time steps. Comparisons to JPL ephemerides for Pallas show errors on the order of 10^-1 to 10^-2 in position and velocity components. While computationally simpler, the two-body model results in significant absolute errors, requiring more detailed force models for precision.
This chapter discusses rotational kinematics, including angular displacement (θ), angular velocity (ω), angular acceleration (α), and time (t). Key relationships are developed between these rotational variables and their linear motion counterparts. Examples are provided to demonstrate calculating angular acceleration, angular displacement, angular velocity, tangential acceleration, centripetal acceleration, and tangential and centripetal forces for objects undergoing rotational motion. Homework problems 1 through 5 at the end of the chapter are assigned.
The document discusses harmonic motion and traveling waves. It defines periodic and harmonic motion, and notes that harmonic motion can be described by a sinusoidal function. Hooke's law relating force and displacement in springs is introduced. Equations of motion for simple harmonic oscillators like masses on springs and pendulums are derived. The relationship between wavelength, frequency and propagation velocity is defined for traveling waves. Solutions to the wave equation for strings and their properties are also summarized.
The document discusses angular motion and rotational dynamics. It defines key terms like angular displacement, velocity, and acceleration. It describes the relationship between torque and angular acceleration through the moment of inertia I, analogous to force and linear acceleration through mass. Equations for rotational motion are provided, obtained by substituting angular terms for linear ones. Examples demonstrate calculating moment of inertia, angular velocity, kinetic energy, angular momentum, and time for various rotational systems.
1) STELLA is a modeling and simulation tool that allows students to explore systems over time and see the relationships between variables. It helps bridge the gap between theory and the real world.
2) A simple pendulum experiment using STELLA showed that the period of a pendulum remains constant as long as the angle of displacement is small (less than 20 degrees). The period is independent of the mass of the pendulum bob but directly proportional to the string length.
3) Various experiments manipulating variables like initial displacement, bob mass, and string length demonstrated the relationships defined by the equations of motion for a simple pendulum. The string length experiment clearly showed the period increases with longer string lengths.
1) The universal reference frame is fixed to the center of mass of the universe, providing a consistent frame to describe the position, velocity, and acceleration of any particle relative to.
2) Equations are provided to calculate the position, velocity, and acceleration of a particle relative to both the universal reference frame and any other reference frame fixed to another particle.
3) The kinetic force between two particles is defined as the product of their masses and relative acceleration divided by the mass of the center of mass of the universe.
W002 - World Visions
Orario 14.30 – 18.00
Sala 4
SPECIAL
GALILEO/EGNOS & GNSS
News and latest activities from the worldwide satellite navigation systems
- Simple harmonic motion describes oscillatory or back-and-forth motion caused by a restoring force proportional to displacement from equilibrium.
- Examples of objects that exhibit simple harmonic motion include springs, pendulums, and waves.
- The period and frequency of oscillation depend on attributes like the spring constant, length, or mass in the case of springs and pendulums.
The document discusses generating ephemerides for asteroids using analytical propagation methods. It begins by introducing the objectives, various coordinate systems, and complexities in determining orbital motion. It then covers the equations of motion for two-body motion and conic orbits. The document describes how to generate ephemerides using analytical techniques by calculating orbital element transformations between time steps. Comparisons to JPL ephemerides for Pallas show errors on the order of 10^-1 to 10^-2 in position and velocity components. While computationally simpler, the two-body model results in significant absolute errors, requiring more detailed force models for precision.
This chapter discusses rotational kinematics, including angular displacement (θ), angular velocity (ω), angular acceleration (α), and time (t). Key relationships are developed between these rotational variables and their linear motion counterparts. Examples are provided to demonstrate calculating angular acceleration, angular displacement, angular velocity, tangential acceleration, centripetal acceleration, and tangential and centripetal forces for objects undergoing rotational motion. Homework problems 1 through 5 at the end of the chapter are assigned.
The document discusses harmonic motion and traveling waves. It defines periodic and harmonic motion, and notes that harmonic motion can be described by a sinusoidal function. Hooke's law relating force and displacement in springs is introduced. Equations of motion for simple harmonic oscillators like masses on springs and pendulums are derived. The relationship between wavelength, frequency and propagation velocity is defined for traveling waves. Solutions to the wave equation for strings and their properties are also summarized.
The document discusses angular motion and rotational dynamics. It defines key terms like angular displacement, velocity, and acceleration. It describes the relationship between torque and angular acceleration through the moment of inertia I, analogous to force and linear acceleration through mass. Equations for rotational motion are provided, obtained by substituting angular terms for linear ones. Examples demonstrate calculating moment of inertia, angular velocity, kinetic energy, angular momentum, and time for various rotational systems.
1) STELLA is a modeling and simulation tool that allows students to explore systems over time and see the relationships between variables. It helps bridge the gap between theory and the real world.
2) A simple pendulum experiment using STELLA showed that the period of a pendulum remains constant as long as the angle of displacement is small (less than 20 degrees). The period is independent of the mass of the pendulum bob but directly proportional to the string length.
3) Various experiments manipulating variables like initial displacement, bob mass, and string length demonstrated the relationships defined by the equations of motion for a simple pendulum. The string length experiment clearly showed the period increases with longer string lengths.
1) The universal reference frame is fixed to the center of mass of the universe, providing a consistent frame to describe the position, velocity, and acceleration of any particle relative to.
2) Equations are provided to calculate the position, velocity, and acceleration of a particle relative to both the universal reference frame and any other reference frame fixed to another particle.
3) The kinetic force between two particles is defined as the product of their masses and relative acceleration divided by the mass of the center of mass of the universe.
W002 - World Visions
Orario 14.30 – 18.00
Sala 4
SPECIAL
GALILEO/EGNOS & GNSS
News and latest activities from the worldwide satellite navigation systems
PHYSICS - Chapter 5: Oscillations Exercise SolutionPooja M
1. The document discusses linear simple harmonic motion (S.H.M.) and provides examples and derivations of key equations related to S.H.M. including expressions for velocity, acceleration, and period of oscillation for a simple pendulum and a magnet vibrating in a uniform magnetic field.
2. It is shown that S.H.M. is the projection of uniform circular motion along any diameter of the circle. Graphs of displacement, velocity, and acceleration versus phase angle are provided for a particle performing S.H.M. from the mean and extreme positions.
3. Key conclusions are that the restoring force in S.H.M. is directly proportional to displacement and acts in the
This document discusses linear motion, forces, and momentum. It includes:
1) Equations for linear motion including displacement, velocity, acceleration, and kinematic equations.
2) Descriptions of linear motion graphs including how to determine velocity and acceleration from displacement-time, velocity-time, and acceleration-time graphs.
3) Definitions of inertia, Newton's First Law of Motion, and momentum as the product of mass and velocity.
4) The principle of conservation of momentum and descriptions of elastic, inelastic, and explosive collisions.
This chapter discusses rotational kinematics and the relationships between linear and rotational motion. Key concepts covered include angular displacement, velocity, and acceleration and how to define and calculate them. Equations are provided relating rotational parameters like displacement, velocity, and acceleration to their linear motion counterparts using variables like radius and arc length. Examples are given calculating values for various rotational motion situations. The chapter aims to help students understand and apply concepts of rotational kinematics.
This document provides an overview of key concepts in waves and sound from Chapter 16. It covers the nature of waves including transverse and longitudinal waves. It discusses topics like speed of waves on a string, mathematical description of waves, nature of sound, and speed of sound. The document is structured with learning objectives, tables of contents, definitions of terms, examples, and conceptual questions.
Ultrasonic guided wave techniques have great potential for structural health monitoring applications. Appropriate mode and frequency selection is the basis for achieving optimised damage monitoring performance.
In this paper, several important guided wave mode attributes are
introduced in addition to the commonly used phase velocity and group velocity dispersion curves while using the general corrosion problem as an example. We first derive a simple and generic wave excitability function based on the theory of normal mode expansion and the reciprocity theorem. A sensitivity dispersion curve is formulated based on the group velocity dispersion curve. Both excitability and sensitivity dispersion curves are verified with finite element simulations. Finally, a
goodness dispersion curve concept is introduced to evaluate the tradeoffs between multiple mode selection objectives based on the wave velocity, excitability and sensitivity.
SPPRA2010 Estimating a Rotation Matrix R by using higher-order Matrices R^n w...Toru Tamaki
Toru Tamaki, Bisser Raytchev, Kazufumi Kaneda, Toshiyuki Amano : "Wstimating a Rotation Matrix R by using higher-order Matrices R^n with Application to Supervised Pose Estimation," Proc. of SPPRA 2010: The Seventh IASTED International Conference on Signal Processing, Pattern Recognition and Applications, pp. 58-64 (2010 02). Innsbruck, Austria, 2010/February/17-19.
This chapter discusses simple harmonic motion (SHM). SHM is defined as periodic motion where the acceleration is directly proportional to and opposite of the displacement from equilibrium. The key equations of SHM are introduced, including the displacement equation x = A sin(ωt + φ) and equations for velocity, acceleration, kinetic energy, and potential energy using angular frequency ω. Examples of SHM include a simple pendulum and spring oscillations. Exercises are provided to apply the kinematic equations of SHM.
The document provides information about various physics concepts related to measurements and motion. It discusses:
1) Base quantities and derived quantities in physics, with base quantities being length, mass, time, temperature, and current. Derived quantities are defined in terms of base quantities.
2) Scalar and vector quantities, with scalars having magnitude but no direction, and vectors having both magnitude and direction.
3) Methods for improving measurement accuracy such as taking multiple readings and calculating an average. Sources of error like parallax error and how to avoid them are also discussed.
4) Examples of measurement tools like vernier callipers and micrometer screws, and how to account for errors like zero error in readings.
1) The document discusses challenging the assumption of an isotropic cosmos by analyzing patterns in the cosmic microwave background (CMB).
2) It summarizes past CMB space missions from 1991-2010 and upcoming missions from 2020 onward that aim to better measure the CMB anisotropy and polarization.
3) Non-parametric methods are presented to analyze the CMB angular power spectrum without assuming a particular cosmological model, allowing estimation of cosmological parameters in a model-independent way.
This document discusses concepts in seismology including:
- P and S wave velocities are represented by symbols α and β or Vp and Vs.
- Seismic velocities depend on properties like bulk modulus, shear modulus, and density.
- There is an empirical relationship between P wave velocity and density known as the Nafe-Drake curve.
- Earthquake locations can be determined by measuring travel times of seismic waves between stations.
This document discusses basic geophysical concepts including:
1) The relationships between various rock physics properties such as density, bulk modulus, shear modulus, Young's modulus, Poisson's ratio, P-wave modulus, and velocities.
2) Factors that influence seismic reflection coefficients such as contrasts in lithology, porosity, saturation, and diagenesis due to their impact on acoustic impedance.
3) Amplitude Variation with Offset (AVO) analysis and the Aki-Richards approximation for P-wave reflectivity as a function of incident angle based on changes in P-wave velocity, S-wave velocity, and density.
Zero outward flow velocity for plasma in a heliosheath transition layeSérgio Sacani
The document summarizes recent findings from Voyager 1, which has been traveling through the heliosheath region between the solar wind termination shock and the heliopause boundary. Key findings include:
1) The radial velocity of plasma detected by Voyager 1 has decreased nearly linearly from 70 km/s to 0 km/s over the past 3 years and has remained at 0 km/s for the past 8 months, indicating Voyager 1 has entered a transition layer with zero radial flow.
2) This transition layer was not predicted by models and contradicts expectations of an abrupt discontinuity at the heliopause.
3) Analysis of plasma velocity measurements suggests Voyager 1 may have crossed the he
Alfvén waves and their kinetic modifications like kinetic Alfvén waves play an important role in space weather and plasma energization processes. Kinetic Alfvén waves are able to dissipate energy and accelerate particles in various regions of space including the solar atmosphere, Earth's magnetosphere during substorms, and in forming features of the solar wind like proton beams. Open questions remain about the detailed theory and observations of kinetic Alfvén wave generation, propagation, and dissipation across different plasma environments.
The document discusses seismic waves, including their properties and how they travel through different materials. It covers topics like:
- Types of seismic waves including P waves and S waves.
- How seismic wave velocities depend on the density and elastic properties of the materials they pass through. Higher density and more mafic minerals increase velocity.
- Empirical relationships between velocity and density like Birch's law and the Nafe-Drake curve, which show velocity and density are directly proportional in most crustal and mantle rocks.
- Factors that affect seismic velocities, with velocity increasing from pressure but decreasing with temperature, fluid presence, or partial melt. S waves don't travel through fluids.
Alpha decay occurs when an unstable nucleus releases an alpha particle to achieve stability. Three key laws are obeyed: conservation of charge, nucleons, and momentum. The alpha particle carries most of the disintegration energy (Q-value) away from the daughter nucleus. Alpha particle velocity and energy can be determined using a magnetic spectrograph which measures particle deflection in a magnetic field. Alpha particles have a well-defined range in a material and become fully absorbed. The Geiger-Nuttall law shows a correlation between an alpha emitter's half-life and the range or energy of its alpha particles.
This document provides an overview of basic principles of seismology. It defines key terms like frequency, wavelength, velocity and discusses wave propagation concepts such as rays, wavefronts and Huygens' principle. It describes how seismic waves (P and S waves) travel through the Earth's interior and surface, depending on properties of the medium like density, bulk modulus and shear modulus. Typical seismic velocities are provided for different earth materials. Factors that can change seismic wave direction and amplitude during propagation are also mentioned.
Quality factor of seismic coda waves in garhwaliaemedu
This document analyzes seismic coda wave attenuation in the Garhwal Himalayan region using data from 75 earthquakes recorded between 2004-2006. Coda quality factor (QC) values were estimated at different frequencies using a lapse time of 50 seconds and four coda window lengths. QC was found to fit a power law relationship with frequency, with exponents ranging from 0.967 to 1.016. Lower QC values at lower frequencies indicate higher attenuation, while higher QC values at higher frequencies indicate lower attenuation, suggesting heterogeneity decreases with depth in the study region.
Quality factor of seismic coda waves in garhwal himalayasiaemedu
This document analyzes seismic coda wave attenuation in the Garhwal Himalayan region using data from 75 earthquakes recorded between 2004-2006. Coda quality factor (QC) values were estimated at different frequencies using a lapse time of 50 seconds and four coda window lengths. QC was found to fit a power law relationship with frequency, with exponents ranging from 0.967 to 1.016. Lower QC values at lower frequencies indicate higher attenuation, while higher QC values at higher frequencies indicate lower attenuation, suggesting heterogeneity decreases with depth in the study region.
Quality factor of seismic coda waves in garhwal himalayas 2IAEME Publication
This document analyzes seismic coda wave attenuation in the Garhwal Himalayan region using data from 75 earthquakes recorded between 2004-2006. Coda quality factor (QC) values were estimated at different frequencies using a lapse time of 50 seconds and four coda window lengths. QC was found to fit a power law relationship with frequency, with exponents ranging from 0.967 to 1.016. Lower QC values at lower frequencies indicate higher attenuation, while higher QC values at higher frequencies indicate lower attenuation, suggesting heterogeneity decreases with depth in the study region.
This document provides an overview of seismic waves:
1) It describes the three main types of seismic waves - P waves, S waves, and surface waves - and how they propagate through the Earth.
2) Key concepts discussed include body waves that travel through the Earth's interior and surface waves that travel along the Earth's surface.
3) The document also discusses seismic wave properties like velocity, period, wavelength, and attenuation as they travel through different Earth layers and are affected by geological structures.
This document provides an overview of seismic waves:
1) It describes the three main types of seismic waves - P waves, S waves, and surface waves - and how they propagate through the Earth.
2) Key concepts discussed include body waves that travel through the Earth's interior and surface waves that travel along the Earth's surface.
3) The document also discusses seismic wave properties like velocity, period, wavelength, and attenuation as they travel through different Earth layers and are affected by subsurface structures.
PHYSICS - Chapter 5: Oscillations Exercise SolutionPooja M
1. The document discusses linear simple harmonic motion (S.H.M.) and provides examples and derivations of key equations related to S.H.M. including expressions for velocity, acceleration, and period of oscillation for a simple pendulum and a magnet vibrating in a uniform magnetic field.
2. It is shown that S.H.M. is the projection of uniform circular motion along any diameter of the circle. Graphs of displacement, velocity, and acceleration versus phase angle are provided for a particle performing S.H.M. from the mean and extreme positions.
3. Key conclusions are that the restoring force in S.H.M. is directly proportional to displacement and acts in the
This document discusses linear motion, forces, and momentum. It includes:
1) Equations for linear motion including displacement, velocity, acceleration, and kinematic equations.
2) Descriptions of linear motion graphs including how to determine velocity and acceleration from displacement-time, velocity-time, and acceleration-time graphs.
3) Definitions of inertia, Newton's First Law of Motion, and momentum as the product of mass and velocity.
4) The principle of conservation of momentum and descriptions of elastic, inelastic, and explosive collisions.
This chapter discusses rotational kinematics and the relationships between linear and rotational motion. Key concepts covered include angular displacement, velocity, and acceleration and how to define and calculate them. Equations are provided relating rotational parameters like displacement, velocity, and acceleration to their linear motion counterparts using variables like radius and arc length. Examples are given calculating values for various rotational motion situations. The chapter aims to help students understand and apply concepts of rotational kinematics.
This document provides an overview of key concepts in waves and sound from Chapter 16. It covers the nature of waves including transverse and longitudinal waves. It discusses topics like speed of waves on a string, mathematical description of waves, nature of sound, and speed of sound. The document is structured with learning objectives, tables of contents, definitions of terms, examples, and conceptual questions.
Ultrasonic guided wave techniques have great potential for structural health monitoring applications. Appropriate mode and frequency selection is the basis for achieving optimised damage monitoring performance.
In this paper, several important guided wave mode attributes are
introduced in addition to the commonly used phase velocity and group velocity dispersion curves while using the general corrosion problem as an example. We first derive a simple and generic wave excitability function based on the theory of normal mode expansion and the reciprocity theorem. A sensitivity dispersion curve is formulated based on the group velocity dispersion curve. Both excitability and sensitivity dispersion curves are verified with finite element simulations. Finally, a
goodness dispersion curve concept is introduced to evaluate the tradeoffs between multiple mode selection objectives based on the wave velocity, excitability and sensitivity.
SPPRA2010 Estimating a Rotation Matrix R by using higher-order Matrices R^n w...Toru Tamaki
Toru Tamaki, Bisser Raytchev, Kazufumi Kaneda, Toshiyuki Amano : "Wstimating a Rotation Matrix R by using higher-order Matrices R^n with Application to Supervised Pose Estimation," Proc. of SPPRA 2010: The Seventh IASTED International Conference on Signal Processing, Pattern Recognition and Applications, pp. 58-64 (2010 02). Innsbruck, Austria, 2010/February/17-19.
This chapter discusses simple harmonic motion (SHM). SHM is defined as periodic motion where the acceleration is directly proportional to and opposite of the displacement from equilibrium. The key equations of SHM are introduced, including the displacement equation x = A sin(ωt + φ) and equations for velocity, acceleration, kinetic energy, and potential energy using angular frequency ω. Examples of SHM include a simple pendulum and spring oscillations. Exercises are provided to apply the kinematic equations of SHM.
The document provides information about various physics concepts related to measurements and motion. It discusses:
1) Base quantities and derived quantities in physics, with base quantities being length, mass, time, temperature, and current. Derived quantities are defined in terms of base quantities.
2) Scalar and vector quantities, with scalars having magnitude but no direction, and vectors having both magnitude and direction.
3) Methods for improving measurement accuracy such as taking multiple readings and calculating an average. Sources of error like parallax error and how to avoid them are also discussed.
4) Examples of measurement tools like vernier callipers and micrometer screws, and how to account for errors like zero error in readings.
1) The document discusses challenging the assumption of an isotropic cosmos by analyzing patterns in the cosmic microwave background (CMB).
2) It summarizes past CMB space missions from 1991-2010 and upcoming missions from 2020 onward that aim to better measure the CMB anisotropy and polarization.
3) Non-parametric methods are presented to analyze the CMB angular power spectrum without assuming a particular cosmological model, allowing estimation of cosmological parameters in a model-independent way.
This document discusses concepts in seismology including:
- P and S wave velocities are represented by symbols α and β or Vp and Vs.
- Seismic velocities depend on properties like bulk modulus, shear modulus, and density.
- There is an empirical relationship between P wave velocity and density known as the Nafe-Drake curve.
- Earthquake locations can be determined by measuring travel times of seismic waves between stations.
This document discusses basic geophysical concepts including:
1) The relationships between various rock physics properties such as density, bulk modulus, shear modulus, Young's modulus, Poisson's ratio, P-wave modulus, and velocities.
2) Factors that influence seismic reflection coefficients such as contrasts in lithology, porosity, saturation, and diagenesis due to their impact on acoustic impedance.
3) Amplitude Variation with Offset (AVO) analysis and the Aki-Richards approximation for P-wave reflectivity as a function of incident angle based on changes in P-wave velocity, S-wave velocity, and density.
Zero outward flow velocity for plasma in a heliosheath transition layeSérgio Sacani
The document summarizes recent findings from Voyager 1, which has been traveling through the heliosheath region between the solar wind termination shock and the heliopause boundary. Key findings include:
1) The radial velocity of plasma detected by Voyager 1 has decreased nearly linearly from 70 km/s to 0 km/s over the past 3 years and has remained at 0 km/s for the past 8 months, indicating Voyager 1 has entered a transition layer with zero radial flow.
2) This transition layer was not predicted by models and contradicts expectations of an abrupt discontinuity at the heliopause.
3) Analysis of plasma velocity measurements suggests Voyager 1 may have crossed the he
Alfvén waves and their kinetic modifications like kinetic Alfvén waves play an important role in space weather and plasma energization processes. Kinetic Alfvén waves are able to dissipate energy and accelerate particles in various regions of space including the solar atmosphere, Earth's magnetosphere during substorms, and in forming features of the solar wind like proton beams. Open questions remain about the detailed theory and observations of kinetic Alfvén wave generation, propagation, and dissipation across different plasma environments.
The document discusses seismic waves, including their properties and how they travel through different materials. It covers topics like:
- Types of seismic waves including P waves and S waves.
- How seismic wave velocities depend on the density and elastic properties of the materials they pass through. Higher density and more mafic minerals increase velocity.
- Empirical relationships between velocity and density like Birch's law and the Nafe-Drake curve, which show velocity and density are directly proportional in most crustal and mantle rocks.
- Factors that affect seismic velocities, with velocity increasing from pressure but decreasing with temperature, fluid presence, or partial melt. S waves don't travel through fluids.
Alpha decay occurs when an unstable nucleus releases an alpha particle to achieve stability. Three key laws are obeyed: conservation of charge, nucleons, and momentum. The alpha particle carries most of the disintegration energy (Q-value) away from the daughter nucleus. Alpha particle velocity and energy can be determined using a magnetic spectrograph which measures particle deflection in a magnetic field. Alpha particles have a well-defined range in a material and become fully absorbed. The Geiger-Nuttall law shows a correlation between an alpha emitter's half-life and the range or energy of its alpha particles.
This document provides an overview of basic principles of seismology. It defines key terms like frequency, wavelength, velocity and discusses wave propagation concepts such as rays, wavefronts and Huygens' principle. It describes how seismic waves (P and S waves) travel through the Earth's interior and surface, depending on properties of the medium like density, bulk modulus and shear modulus. Typical seismic velocities are provided for different earth materials. Factors that can change seismic wave direction and amplitude during propagation are also mentioned.
Quality factor of seismic coda waves in garhwaliaemedu
This document analyzes seismic coda wave attenuation in the Garhwal Himalayan region using data from 75 earthquakes recorded between 2004-2006. Coda quality factor (QC) values were estimated at different frequencies using a lapse time of 50 seconds and four coda window lengths. QC was found to fit a power law relationship with frequency, with exponents ranging from 0.967 to 1.016. Lower QC values at lower frequencies indicate higher attenuation, while higher QC values at higher frequencies indicate lower attenuation, suggesting heterogeneity decreases with depth in the study region.
Quality factor of seismic coda waves in garhwal himalayasiaemedu
This document analyzes seismic coda wave attenuation in the Garhwal Himalayan region using data from 75 earthquakes recorded between 2004-2006. Coda quality factor (QC) values were estimated at different frequencies using a lapse time of 50 seconds and four coda window lengths. QC was found to fit a power law relationship with frequency, with exponents ranging from 0.967 to 1.016. Lower QC values at lower frequencies indicate higher attenuation, while higher QC values at higher frequencies indicate lower attenuation, suggesting heterogeneity decreases with depth in the study region.
Quality factor of seismic coda waves in garhwal himalayas 2IAEME Publication
This document analyzes seismic coda wave attenuation in the Garhwal Himalayan region using data from 75 earthquakes recorded between 2004-2006. Coda quality factor (QC) values were estimated at different frequencies using a lapse time of 50 seconds and four coda window lengths. QC was found to fit a power law relationship with frequency, with exponents ranging from 0.967 to 1.016. Lower QC values at lower frequencies indicate higher attenuation, while higher QC values at higher frequencies indicate lower attenuation, suggesting heterogeneity decreases with depth in the study region.
This document provides an overview of seismic waves:
1) It describes the three main types of seismic waves - P waves, S waves, and surface waves - and how they propagate through the Earth.
2) Key concepts discussed include body waves that travel through the Earth's interior and surface waves that travel along the Earth's surface.
3) The document also discusses seismic wave properties like velocity, period, wavelength, and attenuation as they travel through different Earth layers and are affected by geological structures.
This document provides an overview of seismic waves:
1) It describes the three main types of seismic waves - P waves, S waves, and surface waves - and how they propagate through the Earth.
2) Key concepts discussed include body waves that travel through the Earth's interior and surface waves that travel along the Earth's surface.
3) The document also discusses seismic wave properties like velocity, period, wavelength, and attenuation as they travel through different Earth layers and are affected by subsurface structures.
This document summarizes key aspects of the pseudogap phase in cuprate superconductors. It begins with an overview of the hole-doped phase diagram and experimental probes such as ARPES. It then discusses several notable features of the pseudogap phase revealed by these experiments, including the existence of a gap above the superconducting dome and Fermi arcs that shrink with temperature. Several competing orders that may be related to the pseudogap are also noted. The document concludes with a discussion of BCS-BEC crossover theories as a possible explanation for pseudogap physics in the cuprates based on similarities to phenomena in cold atom systems.
The document discusses key concepts related to optoelectronic devices and communication networks. It covers topics such as optical sources, fiber optics, optical amplifiers, add/drop devices, and optical switches. It also discusses some fundamental properties of light as an electromagnetic wave, including reflection, refraction, polarization, interference, and diffraction. Finally, it reviews key concepts regarding the behavior of light in semiconductors and optical fibers, such as refractive index, total internal reflection, and propagation of modes.
Ray Carlberg: Globular Clusters and Dark-Matter-Halo Vibrations*JeremyHeyl
1) Simulations of globular clusters orbiting within a dark matter halo show that tidal streams form a thin core surrounded by a wider "cocoon" due to the hierarchical assembly of the halo.
2) Streams trace the orbit of their progenitor cluster and can indicate the size of the orbit within the initial subhalo.
3) Collisionless dark matter halos undergo vibrations that induce velocities perpendicular to streams of around 10-20 km/s, but self-interacting dark matter can suppress these velocities.
Wave particle unity and a physically realist interpretation of lightquantumrealism
Welcome to Quantum Realism, we introduce you to the real world of quantum mechanics and scientific realism. Download eBooks about Quantum Mechanics, Scientific Realism etc.
Magnetic fields can confine charged plasma particles by restricting their motion across field lines while allowing motion along field lines. However, external forces or gradients in the magnetic field can cause particles to drift across field lines, breaking confinement. The Earth's magnetic field confines plasma in its magnetosphere and uses this confinement to deflect harmful solar particles, while planetary magnetic fields or artificial magnetic fields can be used to confine fusion plasma or create miniature magnetospheres for planetary protection.
This document discusses the basic principles of seismic waves. It introduces longitudinal (P) waves and shear (S) waves, and derives the one-dimensional wave equation. It discusses wave phenomena like reflection, transmission, and refraction based on Snell's law at boundaries between layers. It also discusses the different arrivals of direct, reflected, and refracted/head waves that can be measured at the surface for seismic exploration purposes.
Gravimetri Dersi için aşağıda ki videoları izleyebilirsiniz.
Link 01: https://www.youtube.com/watch?v=HTyjVaVGx0k
Link 02: https://www.youtube.com/watch?v=fUkfgI8XaOE
The document discusses gravity anomalies and density variations in different regions based on gravity data. It shows how gravity maps reveal details about crustal thickness, tectonic features like faults and volcanic zones, and plate boundaries. Specific examples discussed include the Tibetan Plateau, Central America subduction zone, an area in Chugoku, Japan, and the state of Florida in the US. Regional gravity data can be used to model density changes associated with plate tectonics, crustal evolution, and volcanic and tectonic activity.
The USF team reviewed a geophysical investigation of the Kar Kar region conducted by WesternGeco in 2011. They found that WesternGeco's magnetotelluric (MT) data and models were of high quality. Both the WesternGeco and USF MT models identified a low resistivity zone at 300m depth that correlates with a water-bearing zone found in Borehole 4. USF performed gravity modeling which identified a north-south trending basin reaching 1500m depth, consistent with mapped faults. A preliminary hydrothermal model suggested observed temperatures could result from deep circulation of meteoric waters in the basin without needing a localized heat source. Additional geophysical data is recommended around the Jermaghbyur hot springs to
This document summarizes a study that used gravity data to delineate underground structure in the Beppu geothermal field in Japan. Analysis of Bouguer anomaly maps revealed high anomalies in the southern and northern parts of the study area that correspond to known geological formations. Edge detection filtering of the gravity data helped identify subsurface faults, including the northern edge of the high southern anomaly corresponding to the Asamigawa Fault. Depth modeling of the gravity basement showed differences between the southern and northern hot spring areas, with steep basement slopes along faults in the south and uplifted basement in the north.
This document summarizes the development of a new ultra-high resolution model of Earth's gravity field called GGMplus. Key points:
- GGMplus combines satellite gravity data from GOCE and GRACE with terrestrial gravity data and topography to achieve unprecedented 200m spatial resolution globally.
- It provides gridded estimates of gravity, horizontal and radial field components, and quasi-geoid heights at over 3 billion points covering 80% of the Earth's land.
- GGMplus reveals new details of small-scale gravity variations and identifies locations of minimum and maximum gravity, suggesting peak-to-peak variations are 40% larger than previous estimates. The model will benefit scientific and engineering applications.
Gravity measurements were taken in a region of China covering the south-north earthquake belt in 1998, 2000, 2002, and 2005. Researchers noticed significant gravity changes in the region surrounding Wenchuan and suggested in 2006 that a major earthquake could occur there in 2007 or 2008. While gravity changes were significant at some locations, more research is needed to determine if they could be considered a precursor. Uncertainties exist from measurement errors, hydrologic effects, and crustal movements. Improved data collection and analysis could enhance using gravity monitoring for earthquake research.
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Mind map of terminologies used in context of Generative AI
Elastic Waves
1. Introduction to Seismology-KFUPM
Introduction to Seismology
Chapter 3
Body Elastic Waves
http://faculty.kfupm.edu.sa/ES/oncel/geop204chap3.htm
Chapter 4, Bullen and Bolt
Ali Oncel
oncel@kfupm.edu.sa
Department of Earth Sciences
KFUPM
Introduction to Seismology-KFUPM
http://faculty.kfupm.edu.sa/ES/oncel/geop204presenta.htm
http://faculty.kfupm.edu.sa/ES/oncel/oncellinks.htm
Some Links
http://faculty.kfupm.edu.sa/ES/oncel/geop204link.htm
Introduction to Seismology-KFUPM
Recall: Wave
crests (high points)
equilibrium
(middle)
troughs (low points)
wave speed = wavelength/period = wavelength x frequency.
We often express this as v=fλ
1
2. Introduction to Seismology-KFUPM
Wave Equation
α and β are termed for the P-wave and S-wave
velocities. Often, the symbols Vp and Vs are used
instead of α and β.
Θ is the scalar displacement potential.
Where µ,λ are the Lamé coefficients
where λ is bulk modulus (incompressibility), µ shear
modulus (rigidity) and r density.
Introduction to Seismology-KFUPM
Seismic velocities
P wave velocity α and S wave velocity β depend on
physical properties of medium through which they
travel:
k + ( 4/3)µ λ + 2µ
V = α = = ρ
p
ρ
µ Question: How α and β depend
Vs = β =
ρ on density ρ?
Where µ,λ are the Lamé coefficients and λ is
λ = k - 2µ = νE
3 ( 1 + ν ) ( 1 - 2ν )
Introduction to Seismology-KFUPM
Elastic Coefficients and Seismic
Velocities
Rock Type Density Young's Modulus Poisson's Ratio Vp Vs Vp/Vs Vs as %Vp
r E m (m/s) (m/s)
Shale (AZ) 2.00 0.120 0.040 2454 1698 1.44 69.22%
Siltstone (CO) 2.00 0.120 0.040 2454 1698 1.44 69.22%
Limestone (PA) 2.00 1.100 0.156 7640 4877 1.57 63.84%
Limestone (AZ) 2.00 1.100 0.180 7728 4828 1.60 62.47%
Quartzite (MT) 3.00 0.636 0.115 4675 3083 1.52 65.96%
Sandstone (WY) 3.00 0.140 0.060 2169 1484 1.46 68.42%
Slate (MA) 3.00 0.487 0.115 4091 2698 1.52 65.96%
Schist (MA) 3.00 0.544 0.181 4440 2771 1.60 62.41%
Schist (CO) 2.70 0.680 0.200 5290 3239 1.63 61.24%
Gneiss (MA) 2.64 0.255 0.146 3189 2053 1.55 64.38%
Marble (MD) 2.87 0.717 0.270 5587 3136 1.78 56.13%
Marble (VT) 2.71 0.343 0.141 3643 2355 1.55 64.65%
Granite (MA) 2.66 0.416 0.055 3967 2722 1.46 68.62%
Granite (MA) 2.65 0.354 0.096 3693 2469 1.50 66.85%
Gabbro (PA) 3.05 0.727 0.162 5043 3203 1.57 63.51%
Diabase (ME) 2.96 1.020 0.271 6569 3682 1.78 56.05%
Basalt (OR) 2.74 0.630 0.220 5124 3070 1.67 59.91%
Andesite (ID) 2.57 0.540 0.180 4776 2984 1.60 62.47%
Tuff (OR) 1.45 0.014 0.110 996 659 1.51 66.20%
2
3. Introduction to Seismology-KFUPM
Velocity and Density “Birch’s law”
Crust and mantle rock observations
A linear relationship between density and seismic velocity
where a and b are constants (Birch, 1961). V = a ρ + b
Three pressures
6km 18km 30km
Introduction to Seismology-KFUPM
Nafe-Drake Curve
An important empirical relation, used in joint
interpretation of wide angle reflection and refraction
data and gravity data, exists between P wave velocity
and density.
Cross-plotting velocity and density values of crustal
rocks gives the Nafe-Drake curve after its
discoverers.
Only a few rocks such as salt (unusually low density)
and sulphide ores (unusually high densities) lie off
the curve.
Introduction to Seismology-KFUPM
Nafe-Drake Curve
Sediments and
sedimentary rock
Igneous and
metamorphic rock
Figure 3.10 of Lillie, 1999, modified from Birch, 1960 Reference
L=limestone; Q=quartz; Sh=shale; Ss=sandstone.
3
4. Introduction to Seismology-KFUPM
Factors affecting P-wave velocity
Increases with
mafic mineral content (Nafe-Drake curve)
pressure (modulus change > density change)
Decreases with
temperature (modulus change > density
change)
Introduction to Seismology-KFUPM
Factors affecting S-wave velocity
Increases with
mafic mineral content (Nafe-Drake curve)
with pressure (modulus change > density
change)
Decreases due to
presence of fluid, e.g. porous sand or
partial melt
No S waves in
fluids, e.g. water of molten rock. Velocity
zero
Introduction to Seismology-KFUPM
Velocity-Geology
Grifts and King, 1981
4
5. Introduction to Seismology-KFUPM
Amplitude Changes of Particle Motion
Reference
Maximum amplitude of particle motion occurs along
the 90 degree phase wave front. Other wave
fronts correspond to positions where the wave goes
from positive to negative amplitude (180 degree)
and at the minimum amplitude (270).
Introduction to Seismology-KFUPM
Wave Fronts and Raypaths
Initial wavefronts for
compressional (P),shear
(S), and Rayleigh ( R )
waves.
Changes in velocity cause segments of wave fronts to
speed up or slow down, distorting the wave fronts
from perfect spheres.
Reference
Ray paths thus bend (refract) as velocity changes.
Seismic energy travels along trajectories perpendicular
to wave fronts.
Introduction to Seismology-KFUPM
Seismic Trace
Reference
Seismic waves radiating from a source to one receiver.
Seismic trace recording ground motion by the
receiver, as a function of the travel time from the
source to the receiver. For controlled source studies
(seismic refraction and reflection), the travel time is
commonly plotted positive downward.
5
6. Introduction to Seismology-KFUPM
Introduction to Seismology
Chapter 3
Body Elastic Waves
http://faculty.kfupm.edu.sa/ES/oncel/geop204chap3.htm
Chapter 4, Bullen and Bolt
Ali Oncel
oncel@kfupm.edu.sa
Department of Earth Sciences
KFUPM
Introduction to Seismology-KFUPM
Previous Lecture
Wave equation
Elastic Coefficients and Seismic Waves
Birch's Law
Nafe-Drake Curve
Factors affecting P-wave and S-wave velocity
Seismic velocities for Geological Materials
Amplitude Changes of Particle Motions
Animation: Particle Motion in Seismic Waves
Wavefronts and RayPaths
Seismic Trace
Introduction to Seismology-KFUPM
Recall: Wavefronts and raypaths
nt
fro ular
v e erpendic t3
P
a
le
ang
W
t2
Ray
p ath t1
t0 Com pressional
Source (P) m otion
Shear (S)
m otion
From: http://web.ics.purdue.edu/~braile/edumod/slinky/slinky.htm
6
7. Introduction to Seismology-KFUPM
http://www.geol.binghamton.edu/faculty/jones/SeismicWavesSetup.exe
Seismic Waves A program for the visualization of
wave propagation contributor: Alan Jones
Year: 2006
Introduction to Seismology-KFUPM
From: http://www.citiesoflight.net/AlaskaQuake.html
Introduction to Seismology-KFUPM
Solution for Homework 2
Write up phases of
from 1 to 6?
1
2
3
6
5 4
7
8. Introduction to Seismology-KFUPM
Body Wave Propagation
P- and S- Waves (propagation along raypath)
Earth’s surface
Seismograph X
Y
Source
* SH
SV P-wave particle
motion -- parallel
to direction of
S-wave particle propagation
motion -- perpendicular
to direction of propagation (usually
approximately in SV and SH
Z (down) directions)
Modified from http://web.ics.purdue.edu/~braile/edumod/slinky/slinky.htm
Introduction to Seismology-KFUPM
Introduction to Seismology-KFUPM
Identify the waves of Body and Surface?
8
9. Introduction to Seismology-KFUPM Introduction to Seismology-KFUPM Introduction to Seismology-KFUPM
coast of Chile earthquake recorded at NNA
Three-component seismograms for the M6.5 west
9
10. Introduction to Seismology-KFUPM
Recall: Seismic Wave Types
“body waves” travel in Earth’s interior
P-waves (“P” for primary)
Expansion/compression:
push/pull motion
S-waves (“S” for secondary)
Shear:
side-to-side motion
“surface waves” travel on Earth’s surface
Surface Waves - Body Waves
Introduction to Seismology-KFUPM
Reference
Introduction to Seismology-KFUPM
Seismic Body Waves
Wave Type Particle Motion Other Characteristics
(and names)
P, Alternating compressions P motion travels fastest in
Compressional (“pushes”) and dilations materials, so the P-wave is the
Primary, (“pulls”) which are directed in first-arriving energy on a
Longitudinal the same direction as the seismogram. Generally smaller and
wave is propagating (along the higher frequency than the S and
raypath); and therefore, Surface-waves. P waves in a liquid
perpendicular to the or gas are pressure waves,
wavefront. including sound waves.
S, Alternating transverse S-waves do not travel through
Shear, motions (perpendicular to the fluids, so do not exist in Earth’s
Secondary, direction of propagation, and outer core (inferred to be
Transverse the raypath); commonly primarily liquid iron) or in air or
approximately polarized such water or molten rock magma). S
that particle motion is in waves travel slower than P waves in
vertical or horizontal planes. a solid and, therefore, arrive after
the P wave.
From: www.eas.purdue.edu/~braile/edumod/waves/WaveDemo.htm
10
11. Seismic Surface Waves
Introduction to Seismology-KFUPM
Wave Particle Motion Other Characteristics
Type
(and names)
L, Transverse horizontal Love waves exist because of the Earth’s
motion, perpendicular surface. They are largest at the surface
Love, to the direction of and decrease in amplitude with
Surface propagation and depth. Love waves are dispersive, that is,
waves, Long generally parallel to the the wave velocity is dependent on
waves Earth’s surface. frequency, generally with low frequencies
propagating at higher velocity. Depth of
penetration of the Love waves is also
dependent on frequency, with lower
frequencies penetrating to greater depth.
R, Motion is both in the Rayleigh waves are also dispersive and the
Rayleigh, direction of propagation amplitudes generally decrease with depth in
Surface and perpendicular (in a the Earth. Appearance and particle motion
waves, Long vertical plane), are similar to water waves. Depth of
waves, and “phased” so that penetration of the Rayleigh waves is also
Ground roll the motion is generally dependent on frequency, with lower
elliptical – either frequencies penetrating to greater depth.
prograde or Generally, Rayleigh waves travel slightly
retrograde. slower than Love waves.
From: www.eas.purdue.edu/~braile/edumod/waves/WaveDemo.htm
Downloading the AmaSeis software
Introduction to Seismology-KFUPM
The Using AmaSeis Tutorial:
http://web.ics.purdue.edu/~braile/edumod/as1lessons/UsingAmaSeis/UsingAmaSeis.htm
http://www.geol.binghamton.edu/faculty/jones/AmaSeis.html
Homework due to March, 19: Plot Seismic Trace for one of
available recent earthquakes given by program and try to
explain your observations for Seismic Waves such as Picking
Body Waves, time for S-P and values of maximum amplitude?
11
12. Introduction to Seismology-KFUPM
Seismic Waves of Argentina EQ
Introduction to Seismology-KFUPM
Next Class: Class Presentation
Introduction to Seismology-KFUPM
Introduction to Seismology
Chapter 3
Body Elastic Waves
http://faculty.kfupm.edu.sa/ES/oncel/geop204chap3.htm
Chapter 4, Bullen and Bolt
Ali Oncel
oncel@kfupm.edu.sa
Department of Earth Sciences
KFUPM
12
13. Introduction to Seismology-KFUPM
Previous Lecture
Seismic Wave Types
Revisit: Wavefronts and raypaths
Seismic Waves A program for the visualization of
wave propagation contributor: Alan Jones
Body Wave Propagation
Example: M6.5, 1998 West Coast of Chile Earthquake
Example: Ms7.8, 1999 Izmit Earthquake, Turkey
Revisit: Seismic Wave Types
Downloading the AmaSeis Software
Homework: Seismic Trace Exercise by AmaSeis, Due
to March, 19
Introduction to Seismology-KFUPM
Term Paper:
Refraction
Seismology
Due to March 21
For more detail,
visit to Project
Page of Geop204
http://faculty.kfupm.edu.sa/ES/oncel/geop204termproject.htm
Introduction to Seismology-KFUPM
Travel-Time
Graph
Initial wave fronts for P, S and R waves, propagating
across several receivers at increasing distance from the
source. •Travel time graph. The seismic
traces are plotted according to the
distance (X) from the source to
each receiver. The elapsed time
after the source is fired is the
travel time (T). T=X/V
X distance from source to the receiver,
T total time from the source to the Reference
receiver
V seismic velocity of the P, S, or R
arrival.
13
17. Introduction to Seismology-KFUPM
Reflected/Refracted Waves
A) A compressional wave,
incident upon an interface at
an oblique angle, is split into
four phases: P and S waves
reflected back into the original
medium; P and S waves
refracted into other medium.
See pp.140-152 of Bullen&Bolt
Introduction to Seismology-KFUPM
Seismic Refraction
•Wave fronts are distorted
from perfect spheres as
energy transmitted into
material of different
velocity. Ray paths thus
bend (“refract”) across an
θ1 interface where velocity
θ2
changes.
The angles for incident and refracted are measured from
a line drawn perpendicular to the interface between the
two layers.
Introduction to Seismology-KFUPM
Behavior of
Refracted Ray on
Velocity Changes
17
18. Behavior of Seismic Waves
Introduction to Seismology-KFUPM
Penetrating the Earth
At the mantle-outer core (fluid)
boundary the decrease in
velocity causes those rays
refracted into the core to bend
towards the normal
In the mantle and inner core,
the velocities increase with
depth, so the ray bend away
from the normal
Introduction to Seismology-KFUPM
Recall
Modules of Bulk (k) and Shear (µ)
Bulk Modulus
where Θ = dilatation = ∆V/V
and P = pressure
k= (∆P/Θ)
Ratio of increase in pressure to associated volume change
shear stress = (∆F /A)
shear strain = (∆l /L)
shear modulus
shear stress
µ = shear strain
Force per unit area to change the shape of the material
Introduction to Seismology-KFUPM
Recall
Poisson’s Ratio/Young Module
Poisson’s Ratio
∆L
εxx = σ= ( εyy / εxx )
L
∆W Young Module
εyy = W (∆F /A)
Ε = (∆L/L)
Ratio Vp and Vs depends on Poisson ratio:
where
Poisson’s ratio varies from 0 to ½. The elastic constants E, σ, µ are
Poisson’s ratio has the value ½ for mostly used in works of engineering
fluids seismology because they are easily
measured by simple experiments.
See pp.32 of Bullen&Bolt
18
19. Introduction to Seismology-KFUPM
Recall
Seismic Velocities (P-wave)
See pp.318 and 471 of Bullen&Bolt
Introduction to Seismology-KFUPM
Rock Velocities (m/sec)
pp. 18-19 of Berger
See pp.319 of Bullen&Bolt
Introduction to Seismology-KFUPM
Recall
Influences on Rock Velocities
• In situ versus lab measurements
• Frequency differences
• Confining pressure
• Microcracks
• Porosity
• Lithology
• Fluids – dry, wet
• Degree of compaction
•……………
19
20. Introduction to Seismology-KFUPM
Introduction to Seismology
Refraction and Reflection
Ali Oncel
oncel@kfupm.edu.sa
Department of Earth Sciences
KFUPM
Introduction to Seismology-KFUPM
Previous Lecture
Travel-time Graph
Estimates of Seismic Velocity
Huygens's Principle
Fermat's Principle
Calculation of Travel Times
Snell's law-Critically Refracted Arrival
Reflection/Refraction
Reflected/Refracted waves
Seismic Refraction
Behavior of refracted ray on velocity changes
Behavior of seismic waves refracted ray penetrating
the Earth
Representative P-wave Velocities for various Rocks
Influences on Rock Velocities
Introduction to Seismology-KFUPM
Refracted Ray and Angle
The angle of refraction increases as
the angle of incidence increases.
20
22. Introduction to Seismology-KFUPM
Travel time for
Direct/Refracte
d Waves
Xc=critical distance
Xcr=crossover distance V1 +V 2
T1= Intercept time xcr = 2h1
V2 −V 1
Introduction to Seismology-KFUPM
Seismic
=Z1
Reflection
=Z2
Lillie, Whole Earth Geophysics, Fig 3.28
Reflection occurs when Z1 differs from Z2, where Z
Acoustic impedance which is product of density and velocity
V-shaped ray paths for a compressional wave from a
source to 6 receivers, reflected from a horizontal interface.
Introduction to Seismology-KFUPM
Reflection equation for a reflection hyperbolae:
(X 2
+ 4h 2
)1 / 2
tr =
V 1
22
23. Introduction to Seismology-KFUPM
?
ed
?
ct
fle
ave
Re ad W
Time
do r He
acte
Refr
ti ?
Crossover distance
?
ct
re
Di
Distance
Introduction to Seismology-KFUPM
Introduction to Seismology-KFUPM
IRIS Deployment in Venezuela, 2001
"line" of fifteen Reftek 125 "Texan" recorders
The source of energy:
Betsy M3 Seisgun
From: http://www.passcal.nmt.edu/%7ebob/passcal/venezuela
23
24. Introduction to Seismology-KFUPM
That is what named as “Model 130-01” which was ordered
for ESD in 2006. From: http://www.reftek.com/productshome.html#Seismic%20Recorders
Introduction to Seismology-KFUPM
21 “Texans” from Refraction
Technology, Inc.
From: http://www.seismo.unr.edu/geothermal/
Introduction to Seismology-KFUPM
200 “Texans”
From: http://www.seismo.unr.edu/geothermal/
24
25. Introduction to Seismology-KFUPM
The N. Walker Lane Experiment, 2002
From: http://www.seismo.unr.edu/geothermal/
Introduction to Seismology-KFUPM
How Thick is the Crust?
?
Horizontal Rays
Refraction ?
“Tunneling”
7.2 km/s Moho
Journal Publication: Louie, J. N., W. Thelen, S. B. Smith, J. B. Scott, M. Clark, and S.
Pullammanappallil, 2004, The northern Walker Lane refraction experiment: Pn arrivals
and the northern Sierra Nevada root: Tectonophysics, 388, 253-269.
Introduction to Seismology-KFUPM
The length of profile, which is 180 meter in this case, provided a depth of resolution
to 60 meter but note that velocity in shallow is not detailed due to increased spacing
of receivers (=15 meter)?
KFUPM BEACH-2005
Elevation (m)
180 meter
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26. Introduction to Seismology-KFUPM
In this case, the receiver distance is about 0.4 meter but provided detail information
in depth of very shallow even we could not have info about the detail.
KFUPM-2006
Elevation, m
10 meter
Introduction to Seismology-KFUPM
Class Feedback
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What is one thing you still do not
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