MEASURING PROPERTIES OF LOW PERMEABILITY FORMATIONS
First Claim
1. A method for calculating transmissibility of a subsurface layer using a downhole tool having two packers, a pump, a pressure gauge and means for recording a value indicating the volume of fluid pumped into the formation, wherein said downhole tool:
- isolates an interval of said subsurface layer;
pumps fluid into said isolated interval;
stops pumping after said subsurface layer has fractured; and
records the pressure in said isolated interval for a sufficient period of time to allow the transmissibility of said subsurface layer to be calculated.
1 Assignment
0 Petitions
Accused Products
Abstract
A method for calculating transmissibility, pore pressure, permeability and/or other properties of a subsurface layer comprising the modeling of the borehole pressure recorded from the time the subsurface layer is fractured by isolating said subsurface layer with a downhole tool, pumping fluid into the subsurface layer and stopping pumping said fluid once the formation is fractured until a pseudo-radial or pseudo-linear flow is reached. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
-
Citations
11 Claims
-
1. A method for calculating transmissibility of a subsurface layer using a downhole tool having two packers, a pump, a pressure gauge and means for recording a value indicating the volume of fluid pumped into the formation, wherein said downhole tool:
-
isolates an interval of said subsurface layer; pumps fluid into said isolated interval; stops pumping after said subsurface layer has fractured; and records the pressure in said isolated interval for a sufficient period of time to allow the transmissibility of said subsurface layer to be calculated. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A method for calculating transmissibility of a subsurface layer comprising the steps of:
-
i. positioning a formation tester at said subsurface layer, ii. activating the packers to isolate an interval, iii. pumping fluid into the formation through the space in between the packers, iv. monitoring borehole pressure, v. stopping pumping once the formation has been fractured, vi. monitoring borehole fluid for the period of time needed to achieve pseudo-radial or pseudo-linear flow; and vii. use modeling software to calculate transmissibility of said subsurface layer. - View Dependent Claims (7, 8)
-
-
9. A method for calculating transmissibility of a subsurface layer comprising:
modeling borehole pressure data values that have been recorded from the time said subsurface layer was fractured by isolating said subsurface layer with a downhole tool, pumping fluid into said subsurface layer and stopping pumping said fluid after the formation is fractured until a pseudo-radial or pseudo-linear flow is reached. - View Dependent Claims (10, 11)
Specification