Aperture-size scaling variations in a low-strain opening-mode fracture set, Cozzette Sandstone, Colorado

Fracture abundance and patterns in the Subandean fold and thrust belt, Devonian Huamampampa Formation petroleum reservoirs and outcrops, Argentina and Bolivia

“…For bed-normal, opening-mode fractures in flat-lying or gently dipping beds, fracture spacing of tens of centimeters to many meters has been documented in bed-parallel (horizontal) cores (Gale, 2002;Hooker et al, 2009). It is therefore unsurprising that approximately 20-cm-diameter vertical well bores or 10-cm-diameter cores fail to provide consistent fracture abundance data that can be used to test models that predict subsurface fracture occurrence to the detriment of efficient petroleum development in deep, fractured rocks.…”

“…In sandstones microfractures typically have lengths of millimeters and opening displacements (kinematic apertures) of 0.001 or less to 0.1 mm. Microfractures are useful because in many sandstones they are more abundant than associated macrofractures (Laubach, 1989;Hooker et al, 2009). Because they may also be sealed with cement even where larger fractures are open (Laubach, 2003), these structures may be inconspicuous unless sought using sensitive imaging methods such as cathodoluminescence (CL).…”

Sub-seismic scale fracture pattern and in situ permeability data in the chalk atop of the Krempe salt ridge at Lägerdorf, NW Germany: Inferences on synfolding stress field evolution and its impact on fracture connectivity

“…This is favoured by the evidence that well developed joint patterns can be generated by very small extensional strains (e.g. Hooker et al, 2009;Olson et al, 2009). It is quite common that salt diapirs control the deformation pattern and geometry of hydrocarbon traps in the overlying chalk, which is typically affected by intense extensional fracturing producing tectonic thinning in the diapir overburden (e.g.…”

Characterization of Bedding-Parallel Fractures in Shale - Morphology, Size Distribution and Spatial Organization

“…However, such an approach has shortcomings in terms of only considering present day observed fracture stratigraphy, which can be constantly changing through the history of basin evaluation, sedimentation and deformation (Laubach, 2009).…”