LLL gas stimulation program. Quarterly progress report, April--June 1978

Technical Report · Wed Jul 26 04:00:00 EDT 1978

OSTI ID:6886682

Hanson, M E; Anderson, G D; Shaffer, R J; Hearst, J R; Haimson, B; Cleary, M P

The research and accomplishments of the LLL Gas Stimulation program during the third quarter of Fiscal Year 1978 are summarized. We have used two-dimensional models to analyze the behavior of hydraulically pressurized fractures near well-bonded interfaces that are located between two materials with different mechanical moduli. The results of these calculations indicate that when a fracture in a lower modulus material approaches an interface of a higher modulus material, the Mode I stress-intensity factor at the tip decreases as the crack tip nears the interface. In addition, when the crack tip penetrates the interface, the Mode I stress-intensity factor at that tip is significantly increased. When a pressurized crack in a higher modulus material approaches an interface with a lower modulus material on the other side, just the reverse is true. This report also summarizes research on some of the basic concepts of fracturing including the fundamental problems of the hydraulic fracturing process and crack growth across unbonded interfaces under a normal load. These experiments indicate that different mechanisms may control propagation across sandstone-sandstone and limestone-limestone interfaces.

• Research Organization: California Univ., Livermore (USA). Lawrence Livermore Lab.
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6886682
• Report Number(s): UCRL-50036-78-2
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
030900* -- Natural Gas-- Artificial Stimulation
Plowshare-- (-1989)
COMMINUTION
FAILURES
FRACTURES
FRACTURING
HYDRAULIC FRACTURING
NATURAL GAS WELLS
ORIENTATION
RESEARCH PROGRAMS
ROCK MECHANICS
WELL STIMULATION
WELLS