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Indiana University-Purdue University Indianapolis (IUPUI) / The outwash deposits of the Eel River paleo meltwater channel in DeKalb and Allen Counties, Indiana predominantly originated from the Erie Lobe of the Laurentide Ice Sheet, but do contain some sediment from the Saginaw Lobe. This determination helps clarify the ice dynamics and Last Glacial Maximum sediment depostional history in northeastern Indiana, which is complicated because of the interactions between the Erie and Saginaw Lobes. Outwash deposits were analyzed from IGS core SC0802 in the Eel River paleo meltwater channel, which intersects the previously identified Huntertown Formation. The core includes 29.2 m of deposits underlain by the hard glacial till of the Trafalgar formation. Mean grain size, sediment skewness, lithology, magnetic susceptibility, and quantitative X-ray diffraction were used to evaluate the provenance of the outwash deposits. Representative samples of Erie Lobe and Saginaw Lobe deposits were analyzed to develop end member provenance signatures. A weight of evidence approach was developed and revealed that deposits from 8.0-13.8 m are of mixed origin from the Erie and Saginaw Lobes, whereas the 0-8.0 and 13.8-29.2 m deposits are Erie Lobe in origin. Cluster analysis and discriminant function analysis supported the findings of this approach. These findings suggests that the Eel River paleo meltwater channel was formed as an outwash channel, and that the adjacent Huntertown Formation does not appear to have been directly deposited by the Saginaw Lobe. The sediments of Saginaw origin from ~8-14 m in the Eel River paleo meltwater channel were likely transported from an upgradient source. The sediments from this zone have a larger mean grain size indicating deposition occurred during higher meltwater discharge, such as the release of meltwater from the drainage of proglacial or subglacial lake(s) associated with the disintegration of the Saginaw Lobe, thus resulting in the mixing of Saginaw Lobe deposits with Erie Lobe deposits. However, the majority of the sediment in the Eel River paleo channel near SC0802 is Erie Lobe in origin. Based on the provenance and depositional sequence at SC0802, the Saginaw Lobe disintegrated prior to the Erie Lobe retreat from the Wabash moraine around 16-17 cal ka.

Landslides display a wide variety of behaviors ranging from slow persistent motion to rapid acceleration and catastrophic failure. Given the variety of possible behaviors, improvements to our understanding of landslide mechanics are critical for accurate predictions of landslide dynamics. Recent advances in remote sensing techniques, like satellite radar interferometry (InSAR), now enable high-resolution spatial and temporal measurements that provide insight into the mechanisms that control landslide behavior. In this dissertation, I use InSAR and high-resolution topographic data to identify 50 slow-moving landslides in the Northern California Coast Ranges and monitor their kinematics over 4 years. These landslides have similar mechanical properties and are subject to the same external forcings, which allows me to explore geometrical controls on kinematics. Each landslide displays distinct kinematic zones with different mean velocities that remain spatially fixed. Because these deformation patterns are sensitive to subsurface geometry, I employ a mathematical model to infer landslide thickness and find that these landslides exhibit a highly variable thickness and an irregular basal sliding surface. Time series analysis reveals that each landslide displays well-defined seasonal velocity changes with a periodicity of ∼ 1 year. These velocity variations are driven by precipitation- induced changes in pore-water pressure that lag the onset of rainfall by up to 40 days. Despite significant variations in geometry, I find no systematic differences in seasonal landslide behavior. To further explore how stress perturbations control landslide motion, I develop a mechanical model that reproduces both the displacement patterns observed at slow-moving landslides and the acceleration towards failure exhibited by catastrophic events. I find that catastrophic failure can only occur when the slip surface is characterized by rate-weakening friction and its spatial dimensions exceed a critical nucleation length that is shorter for higher effective stresses. These model simulations support my conclusions from the remote sensing analysis but also provide insight into the long-term evolution of landslides. This dissertation includes both previously published and unpublished co- authored material.

An archaeological survey documenting sites along Upper Eel River within the Indiana counties of Allen, Whitley, Kosciusko and Wabash was conducted during 199192 to collect data which was analyzed to provide a clearer understanding of the region's cultural chronology and describe the area's cultural resources. A total of 765 previously unrecorded sites were documented, 493 of which were field-checked during field reconnaissance of 10% of the project universe, with 1010.82 acres surveyed. A research project completed entirely by volunteers succeeded in locating a number of potential archaeological sites from the Historic Period.Data from the present study securely defined the cultural chronology of the Upper Eel River Valley and yielded valuable information concerning settlement patterns, ecological exploitation, and avenues of migration. Cultural sequencing revealed the presence of Early Paleo-Indians along the river valley at approximately 12,000 B.P. and chronicled the continued expansion of prehistoric populations within the area into historic times. / Department of Anthropology