Conductive medium for openhold logging and logging while drilling
US6405809B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 10, 2001 |
| Grant date | Jun 18, 2002 |
| Priority date | — |
| Expiry date | Jan 10, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/20
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method of electrically logging subterranean wells using a conductive fluid includes a miscible combination of an oleaginous fluid, a polar organic solvent, an electrolytic salt, and a carbon dioxide buffer. The electrolytic salt or brine of the salt is present in a concentration sufficient to permit the electrical logging of the subterranean well. The polar organic solvent may be an oil soluble glycol or glycol ether such as ethylene glycol, diethylene glycol, propylene glycol, polypropylene glycol, and the like. The electrolytic salt or brine preferably includes a quaternary amine salt having the formula: wherein R is an alkyl having 8 to 18 carbon atoms, R′ is 2 to 6 carbon atoms alkyl group, B is hydrogen, oxyalkyl having 1 to 4 carbon atoms or alkyl having 1 to 4 carbon atoms, A is hydrogen or alkyl with 1 to 4 carbon atoms, x+y=1 to 15, z is 0 to 3, and M is a counter anion; or combinations thereof. The carbon dioxide buffer is preferably a trialkylanol amine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.