Publication Name: PESA's Eastern Australasian Basin Symposium II
Authors: M. Wiltshire
Date Published: December 2004
Number of Pages: 25
Reference Type: Book Section
Abstract:
Acoustic waveform data routinely acquired during logging operations is subsequently processed for extraction of P and S wave velocities. The emergent data is then widely used as a basis for interpretation of reservoir properties and fluid content, from both borehole and seismic data. Critical analysis of large volumes of such borehole public domain logging data indicates that the quality of signal extraction is often questionable, and that this is often masked by the form of data presentation and display.Substantial differences are observed between various logging contractors in terms of the integrity of the data presented to clients, whether due to differences in basic acquisition techniques or to differences in expertise and techniques of signal interpretation. A substantial data processing (or post-processing) industry has developed as a result of some operators recognizing problems with such data.
An understanding of the underlying rock physics greatly constrains the range and distribution of basic inter-related wave attributes. By applying basic principles it is possible to perform checks on the supplied data to determine the extent of any problems. Examination of numerous public domain datasets, often from significant wells, indicates that many operators may be unaware of deficiencies in the data.