An integrated field , microstructure, fracture statistic , geochemistry , and laboratory permeability study of the East Fork and White Rock fault zones , of similar age and tectonic regime but different structural level and hydrogeologic history , provides detailed information about the internal deformation and fluid flow processes in fault zones . The primary conclusions of this research are: 1) Fault zones can be separated into subzones of protolith, damaged zone , and gouge /cataclasite , based on physical morphology and permeability structure . At deep structural levels, gouge/cataclasite zones are more evolved (thicker with increased grain size reduction) due to strain localization , higher pressure and temperature, and fluid/rock interaction ; 2) Deformation mechanisms evolved from primarily brittle fracturing and faulting in the damaged zone to extreme, fluid-enhanced chemical breakdown and cataclasis which localized strain in the fault core. Deformation in the deep-level-fault core may be a combination of frictional and quasiplastic mechanisms, and is largely controlled by extremely fine-grained clays, zeolites , and other phyllosilicates that may have acted as a thermally pressurized, fluid-saturated lubricant; 3) Permeability in fault zones was temporally heterogeneous and anisotropic (permeability of damaged zone>protolith>gouge /cataclasite, permeability along fault> permeability across fault); 4) Volume loss was concentrated in the fault cores and was negligible at intermediate structural levels and high at deep structural levels in the semi-brittle to brittle regime ; 5) Fluid flow and solute transport were concentrated upwards and subparallel to the fault in the damaged zone ; 6) Faults at both the local and regional scale acted as fluid flow conduit/barrier systems depending upon the evolutionary stage and interval in the seismic cycle ; 7) Fluid/rock volume ratios , fluid flux , and fluid/rock volume ratios over time ranged from ⋍ 103 to 104, 10-6 ms-1 to 10-9 ms-1, and 0.05 L/m3 rock•yr to 0.50 L/m3 rock•yr, respectively, suggesting that enormous quantities of fluids passed through the fault zones; 8) Box counting fractal analyses of fault zone fractures showed that fracture spatial and density distribution is scale-invariant at the separate scales of outcrop , hand-sample , and thin section, but self-affine from outcrop to thin-section scale; 9) Linear fractal analysis depicts clustering and density distribution as a function of orientation, and may be a quick, robust method of estimating two-dimensional fracture permeability; and 10) Fractal analysis of fractures is not a comprehensive statistical method, but can be used as another supplemental statistical parameter.

Flow-like mass movement is the most destructive landslide and causes loss of lives and substantial property damage throughout the world every year. This thesis focuses on the spatial and temporal changes of the mass movement in terms of velocity and displacement within the failure mass, and the spatial and temporal distribution of the three dimensional internal deformation of the granular slopes using discrete element method, physical experiments, and natural landslides. We have also studied the effect of weak horizons on the kinematics and internal deformation of granular slopes. Numerical model results show the following features related to a failure mass. The failure mass flows downwards in an undulating pattern with a distinctive velocity heterogeneity. Dilatation within the failure mass is strongly dependent on its mechanical properties. A larger mass moves downslope and the mass moves faster and further in the model with lower internal friction and cohesion. The presence of weak horizons within the granular slope strongly influences displacement, location of the failure surface, and the amount of the failure mass. In addition, results from analogue models and natural landslides are used to outline the mode of granular failure. The collapse of granular slopes results in different-generation extensional faults in the back of the slope, and contractional structures (overturned folds, sheath folds and thrusts) in the toe of the slope. The first-generation normal faults with a steep dip (about 60º) cut across the entire stratigraphy of the slope, whereas the later-generation normal faults with a gentle dip (about 40º) cut across the shallow units. The nature of the runout base has a significant influence on the runout distance, topography and internal deformation of a granular slope. Good agreements are found between models and nature for the collapse of granular slopes in terms of the similar structural distribution in the head and toe of the failure mass and different generations of failure surfaces. The presence of a weak horizon within the granular slope has a significant influence on the granular failure and three dimensional internal deformation of the failure mass.

The Nubia plate is normally considered to be a rigid plate and as such used in the realization of terrestrial reference frame. Gondwana breakup plate reconstruction, the Cameroon volcanic line, seismicity, and the morphology of the Okavango rift zone (ORZ) suggest the presence of internal deformation within the Nubia plate. To test this hypothesis, six different reference frames were developed from the velocity field of three individual regions (West, Central and South), and of different combinations of them (West+Central, South+Central, and Nubia as a whole). The residual velocities with respect to these references frame help us understand the presence of the relative motion between the different regions thus the stability of the plate. To realize the reference frames, all the publicly available global positioning system (GPS) data within the “stable” Nubia plate was processed. Given the small relative velocity, it is important to eliminate eventual biases in the analysis and to have good estimates of uncertainty of the observed velocities. For this reason, velocities were analyzed, and rate uncertainties computed using the Allan variance of rate (AVR) technique, accounting for colored noise. Although geological and geophysical studies indicate the possibility of internal deformation within Nubia, the results of this study shows that the current GPS network is not capable to identify intraplate deformation and within uncertainties Nubia is a single plate. As final note, both the color of the noise and the amplitude of the annual signal of each time series as function of latitude and climatic region were analyzed. The study shows that the noise is approximately flicker for all the good stations independently of the location. On the contrary, the amplitude of the annual signal is strongly dependent on the climate of the regions.