An Integrated Approach to Monitoring and Interpreting Ground Deformation at the Currently Active Hengill Volcanic System in Southwest Iceland, Using GIS to Analyze GPS, Seismic

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9901486CliftonThe goal of the research is to quantify the evolution of fracture systems in oblique rift zones using a combination of measurements from scaled clay analog models and field data to determine length-frequency distribution, spatial distribution, geometry, linkage and, connectivity of fractures. Numerous studies conducted during the past 10 years have led to a new and better understanding of how faults grow and how fault populations evolve in extensional tectonic settings. In rifts that are highly oblique to the spreading, whereas in rifts of less obliquity spreading perpendicular faults make a greater contribution to strain accommodation. Scaled physical models are ideal for time-series analysis that can reveal the temporal and spatial evolution of fault systems. Analog models have charted the evolution of rift sub-parallel and spreading perpendicular fractures. The field area selected for study of oblique rifting is the Reykjanes fissure swarm on the Reykjanes Peninsula in Iceland. This first on-shore segment of the Mid-Atlantic Ridge consists of four en echelon fissure swarms. The models represent distributed brittle deformation above a narrow discontinuity that deforms continuously, analogous to the deformation on the peninsula which comprises normal faults, opening mode fissures, and dike-induced grabens narrowly distributed over a volcanic system. Using a combination of field data and data obtained from air photos, the investigator will deduce a temporal evolution similar to what is seen in clay models by analyzing fractures in lava flows of different ages.