Method of treating a subterranean formation with a mortar slurry designed to form a permearle mortar

Patent metadata

Field	Value
Publication number	US-10316636-B2
Application number	US-201313923238-A
Country	US
Kind code	B2
Filing date	Jun 20, 2013
Priority date	Jun 21, 2012
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

A method of treating a subterranean formation may include preparing a mortar slurry, injecting the mortar slurry into the subterranean formation at a pressure sufficient to create a fracture in the subterranean formation, and allowing the mortar slurry to set, forming a mortar in the fracture. The mortar slurry may be designed to form a pervious mortar, to crack under fracture closure pressure, or both.

First claim

That which is claimed is:

1. A method of treating a subterranean formation, comprising:
designing a mortar slurry to set to form a mortar with a compressive strength between 12 MPa and 84 MPa and that is also below a fracture closure pressure of the subterranean formation and above an effective confinement stress, the mortar slurry comprising a cementitious material, water, and sand, wherein the ratio between the sand and the cementitious material in the mortar slurry is from 0.5 to 2.0 parts sand per part of cementitious material by weight;
preparing the mortar slurry;
injecting the mortar slurry into the subterranean formation at a pressure sufficient to create a fracture in the subterranean formation;
while maintaining a pressure higher than the fracture closure pressure, allowing the mortar slurry to set, forming the mortar in the fracture;
reducing the pressure below the fracture closure pressure; and
allowing the mortar in the fracture to crack due to fracture closure pressure, forming a cracked mortar, wherein, prior to allowing the mortar in the fracture to crack, the mortar comprises a pervious mortar having a first conductivity, and wherein the cracked mortar has a second conductivity at least 25 mD-ft greater than the first conductivity.

2. The method of claim 1 , wherein the mortar slurry is further designed to have a viscosity of less than 5,000 cP.

3. The method of claim 1 , wherein the mortar slurry is further designed to set to form the mortar with a setting time in excess of 60 minutes after pump shut in, and wherein allowing the mortar slurry to set comprises waiting at least 60 minutes after injecting stops.

4. The method of claim 1 , wherein the mortar slurry is further designed to set to form a pervious mortar with a conductivity from 25 mD-ft to 2200 mD-ft.

5. The method of claim 1 , wherein the mortar slurry is further designed to set and form the mortar with a salinity tolerance above 1% brine.

6. The method of claim 1 , wherein a design ratio between the water and the cementitious material is between 0.2 and 0.8.

7. A method of treating a subterranean formation, comprising:
designing a mortar slurry to set to form a pervious mortar with conductivity between 25 mD-ft and 2200 mD-ft, with a compressive strength between 12 MPa and 84 MPa and that is also below a fracture closure pressure of the subterranean formation and above an effective confinement stress, the mortar slurry comprising a cementitious material, water, and aggregate, wherein the aggregate comprises sand and the ratio between the sand and the cementitious material in the mortar slurry is from 0.5 to 2.0 parts sand per part cementitious material by weight;
preparing the mortar slurry;
injecting the mortar slurry into the subterranean formation at a pressure sufficient to create a fracture in the subterranean formation and maintaining a pressure on the mortar slurry high enough to prevent fracture closure long enough for the mortar slurry to set;
allowing the mortar slurry to set, forming the pervious mortar in the fracture; and
allowing the mortar in the fracture to crack due to fracture closure pressure.

8. The method of claim 7 , wherein the mortar slurry is further designed to have a viscosity of less than 5,000 cP.

9. The method of claim 7 , wherein the mortar slurry is further designed to set to form the pervious mortar with a setting time in excess of 60 minutes after pump shut in, and wherein allowing the mortar slurry to set comprises waiting at least 60 minutes after injecting stops.

10. The method of claim 7 , wherein the mortar slurry is designed to set to form the pervious mortar with a compressive strength above 20 MPa.

11. The method of claim 7 , wherein the mortar slurry is further designed to set and form the pervious mortar with a salinity tolerance above 1% brine.

12. The method of claim 7 , wherein a design ratio between the water and the cementitious material is between 0.2 and 0.8.

13. The method of claim 7 , wherein the mortar slurry design further comprises retarder.

Assignees

• Shell Oil Co

Inventors

• Fonseca Ernesto Rafael
• Hale Arthur Herman
• Farinas Moya Mauricio Jose
• Verbist Guy Lode Magda Maria
• Van Der Wegen Gerardus Johannes Leonardus
• Van Selst Henricus

Classifications

• E21B43/261 Primary

  Separate steps of (1) cementing, plugging or consolidating and (2) fracturing or attacking the formation · CPC title

• E21B43/267

  reinforcing fractures by propping · CPC title

• C09K8/84

  Compositions based on water or polar solvents (C09K8/66, C09K8/82 take precedence) · CPC title

• C09K8/80 Primary

  Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open · CPC title