Perforating gun assembly and method for enhancing perforation depth

A perforating gun assembly comprising:

• a housing;
• at least one detonator positioned within the housing;
• at least one detonating cord operably associated with the at least one detonator;
• and
• a plurality of shaped charges forming a collection, the shaped charges operably associated with the at least one detonating cord, the collection including two outer shaped charges that converge toward a center shaped charge, wherein the two outer shaped charges are detonated prior to detonating the center shaped charge such that the jets from the two outer shaped charges interact to create a weakened region in the formation and such that the jet from the center shaped charge penetrates through the weakened region, thereby creating a perforation in the formation.

A perforating gun assembly comprising:

• a housing;
• at least one detonator positioned within the housing;
• at least one detonating cord operably associated with the at least one detonator;
• and
• a plurality of collections of substantially axially oriented shaped charges that are operably associated with the at least one detonating cord, each collection of shaped charges in the plurality of collections of shaped charges being circumferentially phased relative to adjacent collections of shaped charges, wherein a first portion of the shaped charges in each collection is detonated forming at least two jets that interact to create a weakened region in the formation and wherein a second portion of the shaped charges in each collection is detonated forming at least one jet that penetrates through the weakened region, thereby creating perforations in the formation.

A method for creating a perforation in a formation behind a wellbore casing, the method comprising the steps of:

• positioning a perforating gun assembly within the wellbore casing, the perforating gun assembly including a plurality of shaped charges that form a collection;
• detonating a first portion of the shaped charges in the collection to form jets that interact with one another to creating a weakened region in the formation;
• and
• detonating a second portion of the shaped charges in the collection to form at least one jet that penetrates through the weakened region, thereby creating the perforation in the formation.

A completion comprising:

• a subterranean formation;
• a wellbore that traverses the formation;
• and
• a casing disposed within the wellbore, wherein the formation has a perforation formed therein as a result of an interaction of jets formed upon the detonation of at least two shaped charges that create a weakened region in the formation followed by the detonation of at least one shaped charge forming a jet that penetrated through the weakened region.