Method for selectively plugging highly permeable zones in a subterranean formation

Patent · Tue Mar 07 00:00:00 EST 1989

OSTI ID:6081694

Hoefner, M L

A method for selectively plugging relatively high permeability zones in a subterranean formation having relatively high permeability zones and relatively low permeability zones penetrated by at least one injection well in fluid communication with a substantial portion of the formation comprising the sequential steps of: (a) injecting a predetermined amount of a solidifiable selective gel solution comprising xanthan chromium (in the 3+ state), sodium hydroxide and formaldehyde in a brine solution containing sodium chloride and calcium chloride into the formation via the injection well at a predetermined pressure sufficient to cause the gel solution to coat and temporarily plug the face of the relatively low permeability zones near the injection well without any significant amount of gel penetrating the relatively low permeability zones while allowing the gel solution to flow into the relatively high permeability zones; (b) thereafter injecting a predetermined amount of a solidifiable non-selective solution comprising polyacrylamides, polysaccharides and unpolymerized acrylamide monomers into the formation via the injection well before the previously injected selective gel solution solidifies in the relatively high permeability zones that preferentially enters the relatively high permeability zones and allowing the injected non-selective solution to solidify and plug the relatively high permeability zones; and (c) injecting a predetermined amount of a flushing agent having a gel breaker into the formation via the injection well that removes the selective gel coating from the face of the relatively low permeability zones thereby restoring permeability of the face of the relatively low permeability zones to fluids subsequently injected into the formation.

• Assignee: Mobil Oil Corp., New York, NY
• Patent Number(s): US 4809781
• OSTI ID: 6081694
• Resource Relation: Patent File Date: Filed date 21 Mar 1988
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
NATURAL GAS WELLS
PLUGGING
OIL WELLS
PLUGGING AGENTS
CHEMICAL COMPOSITION
FLUID INJECTION
GELS
PERMEABILITY
RESERVOIR ROCK
WELL COMPLETION
WELL STIMULATION
COLLOIDS
DISPERSIONS
STIMULATION
WELLS
020300* - Petroleum- Drilling & Production
030900 - Natural Gas- Artificial Stimulation
Plowshare- (-1989)