Poission’s ratio from P- and S-wave traveltimes

**Problems in Exploration Seismology and their Solutions**
Series	Geophysical References Series
Title	Problems in Exploration Seismology and their Solutions
Author	Lloyd P. Geldart and Robert E. Sheriff
Chapter	13
Pages	485 - 496
DOI	http://dx.doi.org/10.1190/1.9781560801733
ISBN	ISBN 9781560801153
Store	SEG Online Store

Problem 13.7

Find Poisson’s ratio for the five events in Figure 13.7a.

Solution

Poisson’s ratio $\sigma$ can be obtained from the ratio $V_{\hbox{P}}/V_{\hbox{S}}$ using equation (10.2) Table 2.2a. Since $z=V_{\hbox{P}}t_{\hbox{P}}=V_{\hbox{S}}t_{\hbox{S}}$ , $V_{\hbox{P}}/V_{\hbox{S}}=t_{\hbox{S}}/t_{\hbox{P}}$ , we can get $(V_{\hbox{P}}/V_{\hbox{S}})$ from the traveltimes and then get $\sigma$ using equation (10,2) (see Table 2.2a), that is,

${\begin{aligned}\sigma ={\frac {(V_{\hbox{P}}/V_{\hbox{S}})^{2}-2}{2[(V_{\hbox{P}}/V_{\hbox{S}})^{2}-1]}}.\end{aligned}}$

Measurements and calculations are listed in Table 13.7a.

**Table 13.7a. Determination of $\sigma$ .**
Event	$t_{\hbox{P}}$	$t_{\hbox{S}}$	$\alpha /\beta$	$(\alpha /\beta )^{2}$	$\sigma$
1	0.39	0.96	2.46	6.05	0.40
2	0.62	1.50	2.42	5.86	0.40
3	0.74	1.65	2.23	4.97	0.37
4	0.80	1.83	2.29	5.24	0.38
5	0.99	2.16	2.18	4.75	0.37

Continue reading

Previous section	Next section
Mapping the vertical flank of a salt dome	Using refraction method to find depth to bedrock
Previous chapter	Next chapter
3D methods	Specialized applications
Table of Contents (book)

Also in this chapter

External links

find literature about
Poission’s ratio from P- and S-wave traveltimes