Lithology identification using sonic data
US5047991A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 21, 1990 |
| Grant date | Sep 10, 1991 |
| Priority date | — |
| Expiry date | May 21, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V1/48
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of identifying lithology of a formation traversed by a borehole from which sonic data is acquired is disclosed. The sonic data acquired comprises a data set of m waveforms, each of the waveforms including a formation wave component digitized into n samples. The formation wave component comprises direct wave components and typically reflected wave components, converted wave components, and noise. A preferred lithology identification method comprising the steps of characterizing the n samples of each formation wave component as a vector, obtaining a first eigenvector based on the formation wave component vectors, selecting a formation wave component vector, calculating a projection of the selected wave component vector on the first eigenvector, and identifying the lithology of the formation through which the selected wave component passed based on the projection of the selected wave component vector on the first eigenvector. If desired, more than one eigenvector may be obtained, and the selected formation wave component vector can be projected on the more than one eigenvectors to identify lithology. Lithology is identified due to the fact that the projection of wave componen…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.