Fracture initiation pressures in permeable poorly consolidated sands

Journal Article · Wed Dec 01 04:00:00 EST 1982 · Int. J. Rock Mech. Min. Sci. Geomech. Abstr.; (United States)

DOI:https://doi.org/10.1016/0148-9062(82)91362-6· OSTI ID:6032824

Horsrud, P; Bratli, R K; Risnes, R

This work studies the stress distribution around an injection well drilled through a layer of poorly consolidated sand. As a plastically strained zone may form around a hole drilled through this type of rock, both elastic and plastic theories must be applied. Solutions have been worked out in order to follow the development of stresses as the injection pressure increases from zero up to the point where a fracture is initiated. How these stresses develop is dependent on the rock and fluid properties, mainly Poisson's ratio and the ratio between the horizontal and vertical stress. Several different stress distributions appear as the injection pressure is increased. Each stress distribution is composed of one or more different stress solutions linked together. This is solved by numeric iteration. The injection pressure is increased until a fracture is induced. Fracture initiation pressures for several different parameter sets were examined. The results were compared with fracture initiation pressures calculated by classical elastic theory. This comparison shows that the fracture initiation pressures can be lower than results calculated by elastic theory. 11 references.

• OSTI ID: 6032824
• Journal Information: Int. J. Rock Mech. Min. Sci. Geomech. Abstr.; (United States), Journal Name: Int. J. Rock Mech. Min. Sci. Geomech. Abstr.; (United States) Vol. 19:6; ISSN IRMGB
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
58 GEOSCIENCES
580300 -- Mineralogy
Petrology
& Rock Mechanics-- (-1989)
COMPARATIVE EVALUATIONS
CRACK PROPAGATION
DRILLING
ELASTICITY
FRACTURE MECHANICS
INJECTION WELLS
MATHEMATICAL MODELS
MECHANICAL PROPERTIES
MECHANICS
OIL WELLS
PLASTICITY
POISSON RATIO
PRESSURE EFFECTS
PRESSURE GRADIENTS
RESERVOIR ROCK
ROCK MECHANICS
ROCKS
SAND
SANDSTONES
SEDIMENTARY ROCKS
STRAINS
STRESS ANALYSIS
STRESSES
TENSILE PROPERTIES
WELL DRILLING
WELLS