Method of developing subsurface barriers

Abstract

A method and apparatus for construction of a subsurface barrier for the recovery of petroleum fluids from the subsurface by steam and/or solvent injection. Multiple propped vertical inclusions at various azimuths and depths are constructed from multiple wells so that the inclusions intersect and coalesce. The inclusions are made impermeable by a variety of means including the proppant swelling to fill the voids of the inclusions. The proppant includes ceramic beads coated with an electrically conductive and heat hardenable resin. The resin is electrically heated and flows to fill the voids in the inclusions as the resin hardens. The proppant includes sand or ceramic beads that are subject to cold saline water circulated between the wells to freeze the formation pore water. The proppant includes low viscosity grout that is injected with a time delay setting agent or electrically conductive grout that is heated and set by electric current passing through the grout.

1 . A method of constructing a barrier in a subterranean formation of unconsolidated, weakly cemented sediments, the method comprising the steps of:
 a) propagating a substantially vertical first inclusion into the formation in a first preferential direction from a substantially vertical central wellbore intersecting the formation;   b) when the viscosity of injected fluid in the first inclusion is not high, propagating a substantially vertical second inclusion from a neighboring well in a same but opposite preferential direction as the first inclusion, the second vertical inclusion to intersect and coalesce with the first vertical inclusion in the same formation.   
     
     
         2 . The method of  claim 1 , wherein the method further includes propagating a plurality of first and second inclusions at varying azimuths. 
     
     
         3 . The method of  claim 1 , wherein the method further includes propagating a plurality of inclusions propagated from the same wellbores at progressively shallower depths when the viscosity of the injected fluid in the immediate lower inclusion is not high, wherein the inclusions at shallower depths intersect and coalesce with the inclusions immediately beneath on their respective azimuths. 
     
     
         4 . The method of  claim 3 , wherein the method includes providing a plurality of injection wells and associated inclusions. 
     
     
         5 . The method of  claim 1 , wherein the inclusions are propagated with a time delay setting grout. 
     
     
         6 . The method of  claim 5 , wherein the grout is of the sodium silicate group. 
     
     
         7 . The method of  claim 5 , wherein the grout is a cement based grout. 
     
     
         8 . The method  claim 1 , wherein the inclusions are propagated with a grout that hardens at elevated temperatures. 
     
     
         9 . The method  claim 1 , wherein the inclusions are propagated with an electrically conductive grout that hardens at elevated temperatures. 
     
     
         10 . The method of  claim 9 , wherein an alternating electric current is passed between neighboring wells, and heats and sets the grout by electric resistive heating. 
     
     
         11 . The method of  claim 1 , wherein the inclusions are propagated with a fluid carrying a proppant. 
     
     
         12 . The method of  claim 11 , wherein the inclusions are propagated with a water based fluid. 
     
     
         13 . The method of  claim 12 , wherein the proppant includes water swellable rubber particles of a size ranging from #4 to #100 U.S. mesh. 
     
     
         14 . The method of  claim 11 , wherein the inclusions are propagated with a hydrocarbon based fluid. 
     
     
         15 . The method of  claim 14 , wherein the proppant includes hydrocarbon swellable rubber particles of a size ranging from #4 to #100 U.S. mesh. 
     
     
         16 . The method of  claim 11 , wherein the proppant particles are of a size ranging from #4 to #100 U.S. mesh are sand or ceramic beads substantially coated with an electrically conductive resin. 
     
     
         17 . The method of  claim 16 , wherein the resin is phenol formaldehyde containing fine graphite particles and is heat hardenable, with resin present in an amount sufficient to fill the voids in the inclusions. 
     
     
         18 . The method of  claim 17 , wherein an alternating electric current is passed between neighboring wells and heats the proppant by electric resistive heating. 
     
     
         19 . The method of  claim 11 , wherein the proppant is a sand or ceramic beads of a size ranging from #4 to #100 U.S. mesh. 
     
     
         20 . The method of  claim 19 , wherein cold high saline water is circulated through the inclusions to freeze formation pore water fluids. 
     
     
         21 . The method of  claim 19 , wherein low viscosity grout is injected into the inclusions with a time delay setting agent. 
     
     
         22 . The method of  claim 21 , wherein the grout is sodium silicate. 
     
     
         23 . The method of  claim 21 , wherein the grout is a cement based grout. 
     
     
         24 . The method  claim 19 , wherein an electrically conductive grout is injected into the inclusions and hardens at elevated temperatures. 
     
     
         25 . The method of  claim 21 , wherein an alternating electric current is passed between neighboring wells, and heats and sets the grout by electric resistive heating. 
     
     
         26 - 50 . (canceled) 
     
     
         51 . The method of  claim 1 , wherein the formation has a Skempton B parameter greater than 0.95 exp(−0.04 p′)+0.008 p′, where p′ is a mean effective stress in MPa at the depth of the first inclusion and the water saturation in the formation pores is greater or equal to 10%.