03933205 is referenced by 117 patents and cites 11 patents.

Well productivity is increased by multiple hydraulic fracturing cycles. A double cycle first creates a long primary fracture by fluid injection and forms spalls by subsequently allowing the pressure in the fracture to drop below the initial fracturing pressure by discontinuing injection and shutting the well in or allowing it to flow back, resuming injection to displace said spalls longitudinally in said fracture and again discontinuing injection, whereupon the fracture is propped open by the displaced spalls.

Multiple applications of this double cycle successively create transversely directed secondary long fractures. Fracture extension and fluid loss is controlled by the sandout of fine spalls at terminal ends of the fractures, supplemented when necessary by the injection of sand of selected size to filter pack the natural joint system and, in some instances, to filter pack the vertical downward extent of joints and fractures thus limiting further fractures to the upper portion of the producing formation where upward leakage is inhibited by the overburden.

Title
Hydraulic fracturing process using reverse flow
Application Number
404691
Publication Number
3933205
Application Date
January 27, 1975
Publication Date
January 20, 1976
Inventor
Othar Meade Kiel
C/O Intercomp Resource Development and Engineering, Inc., 2000 W. Loop S., Houston, 77027
TX, US
Agent
David Alan Rose
Ned L Conley
Murray Robinson
IPC
E21B 43/26
E21B 43/02
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