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Unformatted text preview: Earthquake (15)
Seismic waves Earthquake (16)
Principles Principles Description Description
Vertical seismographe Vertical Horizontal seismograph (at less 2/ station) Horizontal Seismogramm Source: FEMA Source: A. Randrianasolo Earthquake (17)
Vertical (on right) and horizontal (on left) seismograph Recording EQ Earthquake (18)
Seismogram: is a graph output by a seismograph Source: A. Randrianasolo Source: A. Randrianasolo Earthquake (19)
There are two main methods or scales to evaluate the earthquake : Mercalli Scale (measures intensity of EQ; subjective) Richter Scale (measures magnitude of EQ). Earthquake (20)
Mercalli scale Mercalli Usable in inhabited region Usable Correlation: perception + damage / intensity Correlation: Magnitude
Richter scale Richter Measure of energie released Measure M = log(A/T) + F(∆) log(A/T) Today, only Richter method is used. However, the EQs that occurred in the past can only be evaluated using Mercalli’s method. Source P. A. Bourque, 2004 Prof. M. Fall - University of Ottawa 11 ...
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This note was uploaded on 03/21/2011 for the course GNG 4124 taught by Professor Soils during the Spring '11 term at Uni. of Nottingham Ningbo.
- Spring '11