Estimating subsurface formation and invasion properties
US10488547B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 31, 2017 |
| Grant date | Nov 26, 2019 |
| Priority date | — |
| Expiry date | Jan 31, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/20
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An estimated value for invasion depth of an invasion zone in a subsurface measurement zone is calculated in a one-dimensional optimization procedure based on multi-array laterolog measurement data. A one-dimensional optimization problem is defined as having the invasion depth as a sole variable measurement zone parameter. The one-dimensional optimization problem is then solved by automated, iterative modification of the invasion depth value. The one-dimensional optimization problem can be a function to minimize a misfit error between (a) multi-array measurement values for resistivity of the subsurface measurement zone, and (b) predicted measurement values calculated in accordance with a simulated measurement zone model based at least in part on the invasion depth. In one embodiment, the optimization function defines a misfit error between (1) normalized differences between respective measurements of neighboring measurement arrays of the multi-array laterolog tool, and (2) normalized differences between respective predicted measurement values for neighboring measurement arrays.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.