Title: Impairment of Productivity Due to
Fracturing Fluid Leak-off in Oil Reservoirs?
Author(s): B.R. Gadiyar, A. Gupta and S.N. Shah, The
University of Oklahoma
Presentation: SPE Production Operations Symposium
Location: Oklahoma City, Oklahoma USA
Date: March 9-11, 1997
Abstract: This paper presents the results and
interpretation for return permeability testing following the
leak-off of fracturing fluid in reservoir rock samples
containing movable oil saturation. The dynamic fluid loss
tests were conducted with 2 inch diameter and 10 inch lone
core samples. The fluids used were linear guar and
hydroxypropyl guar (HPG), and borate crosslinked guar and
HPG, respectively. Tests were conducted with and without
fluid loss additive (FLA) in order to study its effect on
return permeability impairment. All tests were conducted at
room temperature. The drive pressure during leak-off was 500
psi. Following the leak-off, the cell was shut-in for a
duration of at least 3 hours. In order to obtain the
variation of return permeability with time and distance from
the fracture face, the return permeability was determined
for each 2 inch long section of the core sample. Variation
of return permeability for the specified range of fracturing
fluids is presented and discussed.