Increasing permeability of subsurface formations

Claim 1

IN A METHOD FOR INCREASING THE PERMEABILITY TO FLUIDS OF A SUBSURFACE EARTH FORMATION HAVING AT LEAST ONE FRACTURE EXTENDING FROM THE WALL OF A WELL BORE RADIALLY INTO SAID FORMATION, THE IMPROVEMENT COMPRISING: FORMING A FIRST SUSPENSION OF A SOLID, PARTICLE-FORM MATERIAL AND A CARRIER FLUID, WHEREIN SAID SOLID PARTICLES WILL SETTLE THROUGH SAID CARRIER FLUID AT A RATE GREATER THAN 0.1 FOOT PER MINUTE; INJECTING SAID FIRST SUSPENSION UNDER PRESSURE INTO SAID FRACTURE, WHEREBY SAID SOLID PARTICLES SETTLE TO FORM A SOLID, MULTILAYER PACK IN THE BOTTOM OF SAID FRACTURE; FORMING A SECOND SUSPENSION OF A SOLID, PARTICLE-FORM MATERIAL AND A CARRIER FLUID, WHEREIN SAID SOLID PARTICLES SETTLE THROUGH SAID CARRIER FLUID AT A RATE LESS THAN 0.1 FOOT PER MINUTE; INJECTING SAID SECOND SUSPENSION UNDER PRESSURE INTO SAID FRACTURE, WHEREBY SAID SOLID PARTICLES ARE MAINTAINED IN SUSPENSION IN SAID CARRIER FLUID UNTIL SAID FRACTURE IS PERMITTED TO CLOSE AGAINST SAID SOLID PARTICLES; AND RELEASING THE PRESSURE ON SAID SECOND SUSPENSION TO PERMIT SAID FRACTURE TO CLOSE.