000			02724nab a2200277 4500
005			20260520000318.0
008			260224s2014 xxu ing
041			_aInglés
245	0	0	_aControl of mechanical stratigraphy on bed-restricted jointing and normal faulting _bEagle Ford Formation, south-central Texas
260			_a _b _cnov. 2014
270			_a18/12/2014 ; 18/12/2014
300			_a29 p. ; 2477-2506
520			_aTranscripción del resumen del autor: Outcrops of the middle Eagle Ford Formation in south-central Texas reveal well-developed joint networks in subhorizontal competent carbonate (chalk) beds and less well developed networks in interlayered incompetent calcareous mudrock beds. Northeast-striking bed-perpendicular joints in competent beds have the longest trace lengths and are abutted by northwest-striking joints. All observed joints terminate vertically in incompetent beds. Normal faults are common but less abundant than joints; dominantly dip north, northwest, or southeast; and are abutted by the joint sets and, thus, predated jointing. The faults cut multiple competent and incompetent beds, providing vertical connectivity across mechanical layering. Products of hybrid and shear failure, the dip of these faults is steep through competent beds and moderate through incompetent beds, resulting in refracted fault profiles with dilation and calcite precipitation along steep segments. Fluid inclusions in fault zone calcite commonly contain liquid hydrocarbons. Rare two-phase fluid inclusions homogenized between about (1) 40 and 58°C, and (2) 90 and 100°C, suggesting trapping of aqueous fluids at elevated temperatures and depths on the order of 2 km (6562 ft). Fluid inclusion and stable isotope geochemistry analyses suggest that faults transmitted externally derived fluids. These faults likely formed at depths equivalent to portions of the present-day oil and gas production from the Eagle Ford play in south Texas. Faults connect across layering and provide pathways for vertical fluid movement within the Eagle Ford Formation, in contrast to vertically restricted joints that produce bed-parallel fracture permeability. These observations elucidate natural fractures and induced hydraulic fracturing within the Eagle Ford Formation.
581			_a11
773	0		_tAAPG Bulletin _g98
942			_cARTICULO
100	1		_aFerrill, David A. _913597
100	1		_aMcGinnis, Ronald N. _942961
100	1		_aMorris, Alan P. _913598
100	1		_aSmart, Kevin J. _942960
100	1		_aSickmann, Zachary T. _954320
100	1		_aBentz, Michael _954321
100	1		_aLehrmann, Daniel _954322
100	1		_aEvans, Mark A. _954296
999			_c188714 _d188714