Apparatus and methods for forming formation-to-formation seals in a wellbore

A system for sealing a wellbore extending through a rock formation, wherein the system comprises:

• a delivery apparatus configured to be conveyed within the wellbore, wherein the delivery apparatus comprises a chamber and a separator movably disposed within the chamber;
• a gas producing material disposed within the chamber on a first side of the separator, wherein the gas producing material is configured to undergo an exothermic reaction when ignited, and wherein the exothermic reaction produces a gas;
• and
• a sealing material disposed within the chamber on a second side of the separator, wherein the gas produced by the exothermic reaction is operable to increase pressure within the chamber to force the separator against the sealing material to thereby force the sealing material out of the chamber and into the wellbore such that the sealing material contacts the rock formation, and wherein the sealing material bonds with the rock formation when the sealing material solidifies thereby sealing the wellbore.