Errors of Estimating Near-Surface Q-A statistical Approach

Chih-Sung Chen, Yih Jeng

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DOI: 10.4236/ijg.2011.22017                

Abstract

Although various estimating methods have been developed for measuring Q from near-surface seismic data, less thought has been given to the accuracy of Q obtained. The errors of Q depend on the ways of measuring Q and the computation techniques used in estimating. The main purpose of this paper is to give a compre- hensive evaluation for the accuracy of measuring near-surface Q. We discuss the possible origins from which errors may develop, and provide a statistical guide to the accuracy that can be expected. A set of real data based on the improved spectral ratio method for near-surface Q was used as an example of validation and sensitivity analysis. The Bonferroni procedure was adopted for deriving the joint confidence intervals for k and n of the power law model. The same approach with modest modification may be applied to analyze the accuracy of Q estimated by other methods.

Keywords

Q, Near Surface, Spectral Ratio, Seismic, Statistical Errors

Conflicts of Interest

The authors declare no conflicts of interest.

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