About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

AAPG Bulletin


A Method to Detect Natural Fracture Strike in Sandstones1

Stephen E. Laubach2


In siliciclastic hydrocarbon reservoir rocks, economic gas and oil production may depend on the attributes of natural fractures, and, with the advent of horizontal drilling, fractures are increasingly exploration and development targets; yet reliable information on such key fracture attributes as orientation (strike) is sparse because few fractures intersect vertical well bores. This paper describes how fracture strike can be documented on a bed-by-bed basis even in well bores where few or no visible fractures are directly sampled. Quartz-lined opening-mode microfractures (lengths of microns to millimeters) in quartz-cemented sandstones commonly are not visible using standard petrographic methods, but systematic mapping of these microfractures is possible using photomultiplier-based electron beam-induced luminescence (scanned cathodoluminescence) imaging. As shown by observations, primarily from three natural gas plays and one oil play in the United States, microfracture strike is a good guide to the strike of large fractures (macrofractures) that formed concurrently. Because microfractures are widespread and small specimens can be used to get accurate fracture-strike data, this approach can be applied to samples obtained from wireline-conveyed rotary (drilled) sidewall coring devices, as well as to samples from full-diameter core.

Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Protected Document: $10
Internal PDF Document: $14
Open PDF Document: $24

AAPG Member?

Please login with your Member username and password.

Members of AAPG receive access to the full AAPG Bulletin Archives as part of their membership. For more information, contact the AAPG Membership Department at [email protected].