Method for adaptive filtering of well logging data
US5842158A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 5, 1997 |
| Grant date | Nov 24, 1998 |
| Priority date | — |
| Expiry date | Mar 5, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H21/0012
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The invention described herein provides for an intelligent or "adaptable" filtering method that could be applied when filtering log data. In the present invention, for a given filter model, the adaptive filtering technique differentiates between true changes in the formation or borehole quantity measured and what can be considered to be just a "statistical fluctuation". So, when in long constant-value intervals (data deviations do not exceed those predicted by statistical theory) the filter will automatically increase the number of filter levels used, thereby providing a large reduction (smoothing) of the statistical variations. However, when approaching a spot where there is a true change in the quantity being measured (data deviations over and above those predicted by statistics) the filter will automatically and smoothly decrease, on both sides of this spot, thereby preserving the sharpness of the bed boundary or borehole fluid contact and also preserving the true shape of a thin geologic bed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.