Reflection and transmission of seismic waves under initial stress at the earth's core-mantle boundary

Sukhendu Dey,Sushil Kumar Addy

doi:10.1155/s0161171280000452

Abstract

In the present paper the influence of the initial stress is shown on the reflection and transmission ofPwaves at the core-mantle boundary. Taking a particular value of the inherent initial stress, the variations of reflection and transmission coefficients with respect to the angle of emergence are represented by graphs. These graphs when compared with those having no initial stress show that the effect of the initial stress is to produce a reflectedPandSwaves with numerically higher amplitudes but a transmittedPwave with smaller amplitude. A method is also indicated in this paper to calculate the actual value of the initial stress near the core-mantle boundary by measuring the amplitudes of incident and reflectedPwaves.

Highlights

In the present paper the influence of the initial stress is shown on the reflection and transmission of P waves at the core-mantle boundary
The present paper shows that this initial stress has a significant effect on the reflected and transmitted waves at the core-mantle boundary
Only P wave incident from the mantle side has been considered. This P wave produces reflected P (PCP), reflected S (PCS) and transmitted P waves, each of which is influenced by the initial stress

Summary

Introduction

In the present paper the influence of the initial stress is shown on the reflection and transmission of P waves at the core-mantle boundary. The reflection and transmission of seismic waves at the earth’s core-mantle boundary have been discussed by Dana i I, Ibrahim 2] and many other investigators. From their discussions we see that the reflected and transmitted waves are dependent on elastic parameters, densities and the angle of incidence. The mantle and core contain a considerable amount of initial stress which is compressive and supposed to be hydrostatic in nature (Jeffreys, 3]).

Results

Conclusion