Evolution of rocky coastlines is controlled by littoral, biological and fluvial processes. Resultant landforms are overprinted and/or new ones formed as a result of changes in sea level caused by glacioeustasy and/or local tectonics. On carbonate coasts, chemical erosion in the form of karstification takes on a dominant role. Type of karstification is an important factor in understanding carbonate coast evolution and landform development so it is critical to identify type of karstification. In this research, fractal indices were used to distinguish cave and thus karstification type. It was determined that fractal indices effectively differentiated cave types and the indices were used to distinguish cave types at study sites on Barbados, the ABC Islands (Aruba, Bonaire, Curaçao) and the Caribbean coast of the northeast Yucatan peninsula, Mexico. This research evaluated caves located in the phreatic, epiphreatic and vadose zones of the northeast coast of Quintana Roo, Mexico to determine the relationship between the caves and to coastal processes. Three distinct coastal landforms associated with caves on the study sites were evaluated to quantify and model the interplay of littoral, fluvial and karstic processes and cave and karst development. On Barbados, the combination of surface fluvial processes, and mixing-zone and fluvial-karstic dissolution, resulted in the formation of gullies. Some gullies contained caves in their bounding walls and/or served as points of recharge to fluvial caves. Bokas of the ABC islands are distinctive geomorphic structures that formed from the interplay of fluvial, littoral and mixing zone karstification. The morphology of the bokas was a function of dominant geomorphic process. The caletas of the Yucatan Caribbean were formed by karstification processes that also produced features with mixing-zone-like morphologies but with fluvio-karstic function. The results of this research expand the Carbonate Island Karst Model (CIKM), which explains eogenetic dissolutional processes and landforms on small carbonate islands, to one that includes carbonate islands of all sizes, and carbonate continental coasts.

Evolution geography takes a systems approach to the study of evolution. The interconnected systems include: the gravitational and thermodynamic solar system in which the Earth was formed and resides; the cosmic, solar, electrical, chemical, radioactive and thermal energy flows of Earth; the Earth’s ever-changing biogeochemistry; the dynamic geography of the Earth (deep space); the energy gradients of living matter, which have reciprocally shaped and been shaped by their physical environment for at least 3400 million years (“deep time”); and hominid cultures and civilizations and their ramifications for the Earth's surface over at least the last 60,000 years. We humans are largely unaware of our place or time of evolutionary appearance on Earth. We have had a growing impact on Earth over the last seven centuries. Our over-reliance on reductionism affects the search for knowledge, proliferates and distorts worldviews extrapolated from within narrow disciplines, stifles debate and suppresses novel hypotheses. Data must be mapped into history and context where it can be challenged by other fields, be seen in the context of the evolution of the dynamical Earth system (Gaia). Can humanity trust any worldview to be the basis of good judgment absent the context of Gaia? The evidence is obvious and overwhelming that the answer is “no”.

This thesis is devoted to the investigation of ion generation and fluxes from cathodic arc spots for a better understanding of energetic deposition of thin film. The ion generation is related to the arc spot properties, and ion fluxes influence the film deposition. Significantly, the cathodic arc has the explosion characteristic for the ignition process, which is the generation process of ions. Thus, it is not easy to observe the spot characteristics, and some fundamental questions related to cathodic arc spot motion are still open. The multiply charged ions produced from the arc spot ignition process have a higher ion potential energy than ions of other deposition techniques; therefore, consideration of the effect of ion potential energy on film growth is required for the cathodic arc technique. The first part of this thesis deals with fundamental arc spot characteristics, especially the trend of spot motion in a magnetically steered arc source placed in vacuum or in a reactive gas atmosphere. This is investigated with a streak camera having high spatial and temporal resolutions. To answer the fundamental question of whether the spots have characteristic times, such as a 'periodic spot lifetime' or a 'the periodic characteristic time between spot ignitions”, the streak images were analyzed by fast Fourier transformation (FFT). It was found that the power spectrum of the arc spot fluctuations does not show any specific frequencies, which means the arc spot ignition process can be described by a fractal model, and the spectral slope in the log-log power-frequency diagram has a tendency to be reduced in the presence of a compound (for example oxide or nitride) layer on the cathode surface. Through the fractal analysis and measurements of optical emission spectroscopy, the fundamental limitation of the temporal resolution for the optical emission method is determined and considered. The second part of this thesis considers cathodic arc’s application aspects: the energetic deposition of thin films and coatings. Most studies related to energetic deposition have previously investigated the effects of ion kinetic energy on film deposition; however, this thesis focuses on the effects of ion potential energy on film growth. To investigate the effect of ion potential energy on film growth, plasma diagnostic by energy-resolved mass spectrometry and deposited film characterization by XRD, XRR, AFM, profilometry and SEM were carried out. The ion potential energy influences the preferential direction of film growth or a polycrystalline growth in the case of aluminum deposition. This result could be a starting point for further research into the effect of ion potential energy on film deposition.

Previous experimental and numerical studies focused on incompressible flow interactions with multi-scale fractal structures targeting the generation of turbulence at multiple scales. Depending on various flow conditions, it was found that these fractal structures are able to enhance mixing and scalar transport, and in some cases reduce flow generated sound in certain frequency ranges. The interaction of compressible flows with multi-scale fractal structures, however, did not receive attention as the focus was entirely on the incompressible regime. The objective of this study is to conduct large eddy simulations (LES) of flow interactions with a class of fractal plates in the compressible regime, and to extract and analyze different flow statistics in an attempt to determine the effect of compressibility. Immersed boundary methods (IBM) will be employed to overcome the difficulty of modeling the fractal structures via a bodyitted mesh, with adequate mesh resolution around small features of the fractal shapes.

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