The magnitude of global sediment flux from streams to the oceans over the last 5 Ma is poorly quantified, yet important for predicting future fluxes and deciphering the relative control of tectonic uplift, climate change, vegetation, and related feedback mechanisms on landscape evolution. Despite numerous proxy studies on global sediment delivery to the oceans, it remains uncertain whether bulk sedimentation increased, decreased, or remained approximately constant across one of the most significant global climate changes: the Plio-Pleistocene transition. New developments and strategies in the application of cosmic-ray-produced isotopes, in part developed by this thesis, provide records of pre-historic denudation of confined fluvial catchments in Texas and Yukon. Non-glaciated, tectonically passive regions were targeted in contrast to other studies on modern sedimentation rates in order to isolate the climate influence from glacial and tectonic controls. The results suggest that average catchment temperature, and surficial processes and other factors such as vegetation cover associated with temperature, are the primary controls on the variation in landscape denudation in regions lacking tectonics and direct glacial cover. Specifically, warmer temperatures yield higher denudation rates, both at the scale of glacial-interglacial climate change and over the Plio-Pleistocene transition. The implication is that stream sediment flux to the ocean from tropical and temperate regions was higher during the Pliocene than in the Quaternary. However, this may have been balanced by an increase in sediment flux from regions covered by warm-based glaciers during glacial periods, or by increased temporary continental storage during interglacial periods.

This study concerns Paleo-Indian behaviour and culture history in the central Great Lakes region. More than 15 sites and numerous loci associated with Late Pleistocene and Early Holocene societies in southwestern Ontario are reported. These are organized into archaeological complexes and their interpretation is synthesized into a broader understanding of early occupations in the Northeast. / Complexes are defined by projectile point typology and substantiated by other technological traits and patterns of lithic raw material utilization. Early (fluted point associated) Paleo-Indian complexes are, in suggested chronological order, Gainey, Parkhill, and Crowfield. Late Paleo-Indian complexes are Holcombe and Madina. All date between 11 000 and 10 000 B.P. according to geological considerations, pollen dating, and comparisons to dated materials elsewhere. / Seasonal rounds of resource exploitation within broad territorial ranges are suggested for Gainey and Parkhill populations. Commodity exchange involving particular implement categories provides evidence of band interaction. Mortuary practices and religious beliefs are suggested by possible cremation burials at the Crowfield site. Other significant behavioural patterns are revealed through inter- and intra-site analyses.

The study area is located within the Neogene-Quaternary sequences on top of the Mesozoic accreted mass at the northwest of Kazan (40 km NW of Ankara) between Karalar and Alibey villages. The research deals with the post-Miocene deformational history of an area situated at the southern edge of Galatian Volcanic Province. Two main Neogene rock sequences are cropped out / 1) Late Miocene Pazar Formation, 2) Plio-Quaternary Sinap Formation. The Pazar Formation has a succession composed mainly of clastics at the bottom and, cherts and limestones to the top of the sequence representing a fresh water lake environment. Sedimentation seems to be affected by the intense volcanism going on in the Galatian Volcanic Province. Location of a mammalian fossil found in the Pazar Formation yielded a possible time interval between MN-9 to MN-13 (Middle to Late Miocene). Sinap Formation overlies the Pazar Formation unconformably and it is dominantly represented by fluvial clastics. The post-Miocene deformational studies based on the analysis of the structural data collected from bedding planes and fault planes. Totally 213 dip-strike measurements from the Neogene units and 204 slip lineation data from the fault planes were taken. Fold analysis of dip and strike measurements taken from the Pazar Formation gave a common fold axis trending in N430E direction. Similarly fold analysis for the Sinap Formation resulted N400E striking trend for the fold axis. Stress analysis was performed by processing slip lineation data using Angelier direct inversion method. In the analysis, no reliable results for the post-Miocene compressional phase could be obtained. But the results of the post-Plio-Quaternary extensional regime are strongly reliable. It clearly gives an extension in NW-SE direction. Stress analysis together with the field observations show that the area has been structurally evolved in several phases of deformation. The NW-SE to N-S-directed post-Miocene compressional event is followed by a regional extension operating since Plio-Quaternary.

The Chipola River Valley in northwest Florida is an area of extensive occupation by pre-contact peoples, dating as far back as the Paleo-Indian time period (approximately 11,000 BC). With such a rich archaeological history, it has enticed many local divers to explore river bottoms and collect artifacts. I worked with one local collector to study over 700 projectile points found in the Chipola River. The collector has taken great care to protect and preserve these points and, in many cases, documented the GPS coordinates from where they were collected. Using the GPS coordinates and ArcMap, I have been able to compare where these artifacts were collected to the locations of known archaeological sites which had been previously documented along the Chipola. With this new data set, I used landscape theory to compare prehistoric settlement patterns in the Southeast to the patterns derived from this collection. Overall, this project has documented 80 new sites within the region, filling in areas of the river which previously had no known prehistoric sites. The work also added information for 19 previously-known sites, extending the occupations of some to either later or earlier time periods. Finally, this work can be used to evaluate various models of the early human settlement in the region, specifically the Oasis Model. I hope the success of this project encourages other archaeologists to work with knowledgeable collectors and avocationals to learn more about the archaeological history of different regions.

The triumvirate of tectonics, lithology, and climate control landscape evolution. This study quantifies how lithologic variation and climate-mediated changes in ecosystems perturb steady state processes in the unglaciated, soil-mantled Oregon Coast Range (OCR). I first demonstrate that minor grain-scale differences in rock properties in a seemingly uniform sandstone control differences in rock strength, biotic bedrock-to-soil production efficacy, and erosion rates and influence relief at the watershed scale. I then build on sedimentology, paleoecology, and isotopic-derived paleoerosion data I collected from a new 50 ka sediment archive at Little Lake, OR to explore climate controls on soil production and erosion rates 21 ka across the OCR and spanning 50 ky within a single watershed. In Chapter III, I combine a mechanistic frost weathering model with a regional Last Glacial Maximum (LGM) climate reconstruction and paleovegetation data to demonstrate that accelerated frost-driven erosion was pervasive across the OCR during the LGM. My findings provide a new framework to quantify how the late Pleistocene affects modern erosion and soil formation rates in unglaciated environments and implies that most landscapes reside in a transient state. In Chapter IV, I document climate-mediated ecosystem influence on erosion rates over 3 climatic intervals. 10Be-derived erosion rates increase 3x (from 0.6 mm/yr to 0.21 mm/yr) as the OCR transitioned from the open forest-dominated marine isotope stage (MIS) climate interval (50-26 ka) into the periglacial subalpine MIS 2 glacial interval (26-13 ka). Measured erosion rates fell by more than half as the subalpine ecosystem gave way to the modern MIS 1 closed canopy Douglas-fir forest. Coupling paleovegetation-derived climate information with core observations I model frost weathering intensity from ~ 43 ka to 21 ka and establish a correspondence with increasing frost weathering intensity and increasing 10Be-derived erosion rates. Utilizing a transient mixing depth and erosion rate model, I am able to broadly replicate measured erosion rates at Little Lake through time. My findings contradict previous work that suggests climate has only weak control on erosion rates. This dissertation includes previously published and unpublished co-authored material.

The Manassas oil field was discovered in 1986 in Lincoln County, Colorado (Township 14S, Range 56W) by Petro Lewis Corporation and it completed production from the Pennsylvanian Atoka Sandstone within 24 years. It is located on the theoretical NW extension of the Haswell-Salt Lake Morrow sandstone producing trend and Morrow sandstones have found in some of the available wells in the area. The productive Morrow sandstones are fluvial channel deposits that are encased by marine shales. The distribution of the Morrow channel system is difficult to define from either data obtained from sparsely located wells alone, or directly from seismic data due to low acoustic contrast between fluvial sandstones and marine shale. Therefore, this study has used a correlation of well log data to understand regional stratigraphy of the selected study area and seismic attributes were used to develop a workflow to define the Morrow sandstone channel system in the Manassas prospect. Well logs from forty wells were used to define the early Pennsylvanian strata (Marmaton, Cherokee, upper and lower Atoka, upper and lower Morrow) and underlying Mississippian unit (St. Louis). The formation data were used to visualize the regional stratigraphy using isopach maps and stratigraphic cross sections. The acoustic and density logs from the Lockwood 27-22 well located in the Manassas field, were used to generate the synthetic seismogram for the purpose of seismic horizons interpretation. The upper Morrow isochron thick was defined using upper and lower Morrow time structure maps. The channel infill system was first detected using the Chaos attribute that identifies reflectors associated with channel infills that are normally chaotic signals with low consistency. The observation was confirmed using, Variance attribute that analyzes signal coherency, and estimates trace to trace variance. The amplitude attributes (RMS Amplitude – iterative attribute, and Envelope) highlight both channel infills and bright spots. The Genetic Inversion identifies relative variations of rock properties. The Generalized Spectral Decomposition attribute was used to visualize the detailed channel morphology through generating a RGB blending model as the final step. This study shows that the Morrow channel sandstones are present across the Manassas prospect and are interpreted as a composite meandered and anastomosed channel system. The observed high amplitude variations are interpreted as tuning effects of thin beds and relative lithological changes caused by variations of rock properties such as density and porosity.

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