02643nab a2200241 4500 20260520000317.0 260224s2014 xxu ing Inglés Natural fractures in shale A review and new observations nov. 2014 09/12/2014 ; 09/12/2014 51 p. ; 2165-2216 Transcripción del resumen del autor: Natural fractures have long been suspected as a factor in production from shale reservoirs because gas and oil production commonly exceeds the rates expected from low-porosity and low-permeability shale host rock. Many shale outcrops, cores, and image logs contain fractures or fracture traces, and microseismic event patterns associated with hydraulic-fracture stimulation have been ascribed to natural fracture reactivation. Here we review previous work, and present new core and outcrop data from 18 shale plays that reveal common types of shale fractures and their mineralization, orientation, and size patterns. A wide range of shales have a common suite of types and configurations of fractures: those at high angle to bedding, faults, bed-parallel fractures, early compacted fractures, and fractures associated with concretions. These fractures differ markedly in their prevalence and arrangement within each shale play, however, constituting different fracture stratigraphies—differences that depend on interface and mechanical properties governed by depositional, diagenetic, and structural setting. Several mechanisms may act independently or in combination to cause fracture growth, including differential compaction, local and regional stress changes associated with tectonic events, strain accommodation around large structures, catagenesis, and uplift. Fracture systems in shales are heterogeneous; they can enhance or detract from producibility, augment or reduce rock strength and the propensity to interact with hydraulic-fracture stimulation. Burial history and fracture diagenesis influence fracture attributes and may provide more information for fracture prediction than is commonly appreciated. The role of microfractures in production from shale is currently poorly understood yet potentially critical; we identify a need for further work in this field and on the role of natural fractures generally. 11 AAPG Bulletin 98 ARTICULO Gale, Julia F.W. 38548 Laubach, Stephen E. 42957 Olson, Jon E. 12292 Eichhubl, Peter 19605 Fall, András 52917 188703 188703 0 0 0 0 256522 BAAB BAAB 2026-03-06 200060910 0 200060910 2026-03-06 00:18:46 2026-03-06 ARTICULO