A method for isolating subterranean formations or zones intersected by a single wellbore is provided. The method comprises perforating a zone intersected by the wellbore and pumping a sealing means into the wellbore to seal against the side of the casing above and below the perforations to prevent communication from the zone into the wellbore after the casing has been perforated. The method further comprises fracturing the zone through the perforations prior to sealing and thus isolating the zone. Other zones thereabove are likewise perforated, fractured, sealed and thus isolated by pumping sealing means into the wellbore to seal the casing adjacent the perforations to prevent communication from the affected zones into the wellbore.

A system and method for perforating and gravel packing a wellbore casing in a single trip into the wellbore comprising a gravel packer assembly having a production screen and at least one packer. A perforating apparatus connected to the gravel packer assembly, wherein the perforating apparatus is detachable from the gravel packer assembly after the system is placed in the wellbore and before a detonation of the perforating apparatus. A tool having at least one casing engaging slip segment, wherein the tool is matable with the perforating apparatus and is settable in the wellbore casing.

A gravel packing method combining fracturing is described. A gun having an exterior auger is used to perforate. With the gun in place, the gravel is positioned around it and the formation is fractured, pushing the gravel into the fractures. The gun is rotated out of the gravel using the auger. A screen with an external auger is run in and rotated into the packed gravel in the wellbore while being vibrated at the same time. After the screen is advanced into position the vibrator is removed and a flapper closes to minimize fluid loss into the formation. A production string and packer are tagged into the screen and production begins.

A method for assembling a stackable perforating gun system inside a well bore is provided that includes attaching a first gun section of the stackable perforating gun system to a tracking assembly, and transporting the first gun section within the well bore using the tracking assembly. The method also includes disengaging the first gun section from the tracking assembly; retrieving the tracking assembly to the surface; attaching a second gun section of the stackable perforating gun system to the tracking assembly; transporting the second gun section within the well bore using the tracking assembly; and coupling the second gun section with the first gun section using the tracking assembly.

A method of perforating and gravel packing a wellbore casing, having the following steps: (1) making-up to a pipe string: a packer, a screen, and a perforating apparatus; (2) running-in the pipe string until the perforating apparatus is at a depth of intended perforations; (3) setting the perforating apparatus in the wellbore casing at a depth of intended perforations; and (4) disconnecting the screen and perforating apparatus from the pipe string. A system for perforating and gravel packing a wellbore casing, having: a packer which is mechanically communicable with a service string: a screen in mechanical communication with the packer; a perforating apparatus in mechanical communication with the screen, wherein the screen and perforating apparatus are detachable from the packer; and a tool having at least one casing engaging slip segment, wherein the tool is matable with the perforating apparatus, and wherein the tool is settable in the wellbore casing.