Forming perturbed in-line perforations

Abstract

A bottom hole assembly includes a downhole conveyance that is extendable from a terranean surface, through a wellbore, and to a subterranean formation; and a perforating tool configured to couple to the downhole conveyance and create a perforation cluster in the subterranean formation. The perforation cluster includes perforations arranged along a longitudinal direction of the wellbore. The perforations includes one or more first perforations extending along a first azimuthal direction, one or more second perforations extending along a second azimuthal direction at a first offset angle with respective to the first azimuthal direction, and one or more third perforations extending along a third azimuthal direction at a second offset angle with respective to the first azimuthal direction. The one or more second perforations and the one or more third perforations are alternative with each other along the longitudinal direction of the wellbore.

What is claimed is: 
     
         1 . A bottom hole assembly, comprising:
 a downhole conveyance that is extendable from a terranean surface, through a wellbore, and to a subterranean formation; and   a perforating tool configured to couple to the downhole conveyance and create a perforation cluster in the subterranean formation, the perforation cluster comprising perforations arranged along a longitudinal direction of the wellbore, the perforations comprising one or more first perforations extending along a first azimuthal direction, one or more second perforations extending along a second azimuthal direction at a first offset angle with respective to the first azimuthal direction, and one or more third perforations extending along a third azimuthal direction at a second offset angle with respective to the first azimuthal direction, the one or more second perforations and the one or more third perforations being alternative with each other along the longitudinal direction of the wellbore.   
     
     
         2 . The bottom hole assembly of  claim 1 , wherein the one or more second perforations are even-numbered perforations, and the one or more third perforations are odd-numbered perforations. 
     
     
         3 . The bottom hole assembly of  claim 1 , wherein the first offset angle and the second offset angle range between about 0 degree and about 25 degrees. 
     
     
         4 . The bottom hole assembly of  claim 1 , wherein at least one of the second azimuthal direction or the third azimuthal direction is different than the first azimuthal direction. 
     
     
         5 . The bottom hole assembly of  claim 1 , wherein the first offset angle is equal in magnitude and opposite in sign to the second offset angle. 
     
     
         6 . The bottom hole assembly of  claim 5 , wherein the first offset angle is about −10 degrees, and the second offset angle is about +10 degrees. 
     
     
         7 . The bottom hole assembly of  claim 1 , wherein the first offset angle is unequal in magnitude and opposite in sign to the second offset angle. 
     
     
         8 . The bottom hole assembly of  claim 7 , wherein the first offset angle is about −10 degrees, and the second offset angle is about +25 degrees. 
     
     
         9 . The bottom hole assembly of  claim 1 , wherein the perforating tool comprises shaped charges, detonating directions of the shaped charges being phased at azimuths smaller than about 60 degrees. 
     
     
         10 . The bottom hole assembly of  claim 1 , wherein the perforation cluster comprises 6 perforations within a foot. 
     
     
         11 . The bottom hole assembly of  claim 1 , wherein the perforating tool comprises a high-pressure coiled tubing jetting tool, a laser tool, or an abrasive jet perforating tool. 
     
     
         12 . A bottom hole assembly, comprising:
 a downhole conveyance that is extendable from a terranean surface, through a wellbore, and to a subterranean formation; and   a perforating tool configured to couple to the downhole conveyance and create a perforation cluster in the subterranean formation, the perforation cluster comprising perforations arranged along a longitudinal direction of the wellbore, the perforations comprising one or more first perforations extending along a first azimuthal direction, second perforations extending along second azimuthal directions at first offset angles with respective to the first azimuthal direction, and third perforations extending along third azimuthal directions at second offset angles with respective to the first azimuthal direction, the first offset angles being opposite to the second offset angles in sign, and at least two of the second azimuthal directions being different from each other.   
     
     
         13 . The bottom hole assembly of  claim 12 , wherein the second perforations and the third perforations are alternative with each other along the longitudinal direction of the wellbore. 
     
     
         14 . The bottom hole assembly of  claim 12 , wherein the first offset angles and the second offset angles are between about 0 degree and about 25 degrees. 
     
     
         15 . The bottom hole assembly of  claim 12 , wherein at least two of the third azimuthal directions are different from each other. 
     
     
         16 . The bottom hole assembly of  claim 12 , wherein each of the perforations extends along a unique direction. 
     
     
         17 . The bottom hole assembly of  claim 12 , wherein the perforating tool comprises high-pressure coiled tubing jetting tools, laser tools, or abrasive jet perforating tools. 
     
     
         18 . A method to form a perforation cluster, comprising:
 positioning a perforating tool adjacent a subterranean formation within a wellbore; and   operating the perforating tool to form a perforation cluster in the subterranean formation, the perforation cluster comprising perforations arranged along a longitudinal direction of the wellbore, the perforations comprising one or more first perforations extending along a first azimuthal direction, one or more second perforations extending along a second azimuthal direction at a first offset angle with respective to the first azimuthal direction, and one or more third perforations extending along a third azimuthal direction at a second offset angle with respective to the first azimuthal direction, the first offset angle opposite to the second offset angle in sign.   
     
     
         19 . The method of  claim 18 , wherein the first offset angle and the second offset angle are between about 0 degree and about 25 degrees. 
     
     
         20 . The method of  claim 18 , wherein the first offset angle is equal to the second offset angle in magnitude. 
     
     
         21 . The method of  claim 20 , wherein the first offset angle is about −10 degrees, and the second offset angle is about +10 degrees. 
     
     
         22 . The method of  claim 18 , wherein the perforation cluster comprises 6 perforations within a foot. 
     
     
         23 . The method of  claim 18 , wherein operating the perforating tool comprises operating a high-pressure coiled tubing jetting tool, a laser tool, or an abrasive jet perforating tool. 
     
     
         24 . The method of  claim 18 , wherein the perforations comprise:
 a first set of in-line perturbed perforations arranged along a first longitudinal direction of the wellbore, the first longitudinal direction being vertical at an azimuth of 0 degrees; and   a second set of in-line perturbed perforations arranged along a second longitudinal direction of the wellbore, the second longitudinal direction being horizontal at an azimuth of 90 degrees.   
     
     
         25 . The method of  claim 24 , wherein each of the first and second sets of in-line perturbed perforations comprises at least 6 perforations.