; R o o t E n t r y F N C o m p O b j b W o r d D o c u m e n t E O b j e c t P o o l N N 4 @ % & ' ( ) * + , - . / F Microsoft Word 6.0 Document MSWordDoc Word.Document.6 ; v v ^ && _ u u f M ^ & W & G V F ^ & GXP v v '5 F ~ t j ^ & w,& w* S o5 F ~ t v v ^ && _8 F f M f M EU VW ^ & W & G V F ^ & W & G ^ & O & _ ; u ; t O1 u ^ & w & w O6 ^ & O & O u 9526047 Twiss This is a collaborative project to continue investigation of the application of micropolar continuum theory to the analysis of brittle deformation. This research consists of theoretical and applied elements, both of which have significant implications for the study of active tectonics. Seismic events and slickenlines on fault surfaces are manifestations of slip on shear planes that occurs in the brittle part of the Earth s crust. The slip accommodates a specific geometry of deformation of defined by the orientation of the fault and the direction of slip. The set of all such shearing events in a given volume accommodates the brittle deformation of that volume. If we assume that this brittle deformation is an accurate reflection of the tectonic deformation imposed, that we can invert the seismic focal mechanism data or the shear plane/slickenline data to determine the geometry of the tectonic deformation. The inversion of such data requires a deformation model that one fits to the observations. The micropolar model of deformation is a continuum model that includes the effects o f the rotation of rigid fault blocks on the slip directions in any given shear plane, which other deformation models do not include. Thus, using this model permits the extraction of more kinematic detail from the data than other inversion techniques provide. ; Oh +' 0 $ H l D h R:WWUSERTEMPLATENORMAL.DOT S u m m a r y I n f o r m a t i o n ( $ 9526105 Felicia Smith Felicia Smith @ M?L @ @ M?L @ Microsoft Word 6.0 2 ; e = e a E a j j j j j j j 1 " " " A m T 5 j j j j j ~ j j j j x 9526047 Twiss This is a collaborative project to continue investigation of the application of micropolar continuum theory to the analysis of brittle deformation. This research consists of theoretical and applied elements, both of which have significant implications for the study of active tectonics. Seismic events and slickenlines on fault surfaces are manifestations of slip on shear planes that occurs in the brittle part of the Earth s crust. The slip accommodates a specific geometry of deformation of defined by the orientation of the fault and the direction of slip. The set of all such shearing events in a given volume accommodates the brittle deformation of that volume. If we assume that this brittle deformation is an accurate reflection of the tectonic deformation imposed, that we can invert the seismic focal mechanism data or the shear plane/slickenline data to determine the geometry of the tectonic deformation. The inversion of such data requires a deformation model that one fits to the observations. The micropolar model of deformation is a continuum model that includes the effects of the rotation of rigid fault blocks on the slip directions in any given shear plane, which other deformation models do not include. Thus, using this model permits the extraction of more kinematic detail from the data than other inversion techniques provide.
