Low-water-pressure controlled hydrologic test method
US4986120A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jun 6, 1989 |
| Grant date | Jan 22, 1991 |
| Priority date | — |
| Expiry date | Jun 6, 2009 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B49/008
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A low-water-pressure-controlled hydrologic test using a measurement pipe containing an inner packer which is equipped with a water pressure gage at its tip is disclosed. Some water is poured into the measurement pipe in advance so as to diminish the pressure head difference between the in-pipe pressure and the pore water pressure of the rock concerned. The permeability coefficient is obtained by measuring changes in the recovered water level in terms of pressure changes. In the case of an aquiclude, the inner pressure is raised by expanding the inner packer, the permeability coefficient being obtained by detecting the changes in inner pressure. Thus, the method allows a permeability test to be conducted continuously at various depths. In addition, it helps to shorten the measurement time to a remarkable extent and enables the rock condition to be investigated without departing from the natural condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.