000			02392nab a2200229 4500
005			20260520000319.0
008			260224s2015 xxu ing
041			_aInglés
245	0	0	_aStructural and chemical controls of deformation bands on fluid flow _bInterplay between cataclasis and diagenetic alteration
260			_a _b _cabr. 2015
270			_a18/06/2015 ; 18/06/2015
300			_a21 p. ; 689-710
520			_aTranscripción del resumen del autor: We examined cataclastic shear bands (CSB) with varying degrees of deformation and alteration that formed in uncemented, arkosic sediments under identical kinematic conditions. The investigated outcrop in eastern Austria exposes numerous closely spaced sets of CSB formed at low burial depth. The uncemented host sediment consists of detrital quartz, albite, micas, and metamorphic lithoclasts. We distinguished three types of CSB, which differ in macroscopic and microscopic properties as well as in influence on fluid flow (i.e., single bands, multistrand bands, and band clusters). All band types show preferred fracturing of sericited albite grains and decomposition of biotite through mechanical deformation and subsequent chemical alteration. These mechanisms reduce the mean grain size, increase the amount of phyllosilicates in the matrix, and facilitate later growth of authigenic clay minerals. The dominant deformation mechanisms and influence on fluid flow are controlled by the initial composition and intensity of diagenetic alteration. We identified different evolutionary stages from a high-porosity host rock (BLTN13162eq1) to a deformation band cluster (BLTN13162eq2) that acts as fluid baffle. The measured reduction in porosity of up to 29% is reflected by retention of fluids along band clusters, along multistrand bands, and between intersecting bands. The timing and direction of the specific fluid flows can be determined by the interaction with the deformation bands. These findings suggest that localized deformation and associated diagenetic alteration in feldspar-bearing sediments may promote reservoir compartmentalization.
581			_a4
773	0		_tAAPG Bulletin _g99
942			_cARTICULO
100	1		_aLommatzsch, Marco _954528
100	1		_aExner, Ulrike _951582
100	1		_aGier, Susanne _954529
100	1		_aGrasemann, Bernhard _950735
999			_c188936 _d188936