Statistical measures of crustal heterogeneity from reflection seismic data: The role of seismic bandwidth
Article first published online: 7 DEC 2012
Copyright 1999 by the American Geophysical Union.
Geophysical Research Letters
Volume 26, Issue 21, pages 3241–3244, 1 November 1999
How to Cite
- Issue published online: 7 DEC 2012
- Article first published online: 7 DEC 2012
- Manuscript Accepted: 8 SEP 1999
- Manuscript Received: 15 JUN 1999
In recent years there has been a growing realization that geological media vary over a broad scale range. As such heterogeneity cannot be described in a deterministic way, a parallel growth in stochastic analyses of geological/geophysical data has emerged. The stochastic description of these media is usually through some form of correlation function, of which the von Karman is the most widely employed. Using this form, media can be described in terms of a characteristic scale size (or correlation length), L and a coloured scaling regime, with scaling described by H, the Hurst exponent. Beyond the correlation length, the material follows a white noise spectrum where material average properties dominate, below the correlation length local heterogeneity dominates. Hence, the correlation length is a fundamental parameter in a range of geodynamical problems. In situ information about stochastic properties of deep crustal rocks can be obtained from the statistical analysis of reflection seismic data. Typical correlation distances within the crust are found to be several hundred metres. Here we show that correlation distances derived from reflection seismic data are strongly influenced by the spectral content of the source. In particular we conclude that there is no reliable evidence for hundred metre scale correlation lengths for crustal heterogeneity.