New, dated impacts discovered on Mars and the Moon provide direct observations of modern bombardment in the inner Solar System and the freshest available examples of recent craters. Their population, morphology, formation and modification processes relate to issues with secondaries and help calibrate cratering chronology models. I use a subset of the new impacts to measure the current production function at Mars. The resulting production function is a factor of approximately four lower than widely-used models, and the size frequency distribution has a shallower slope. This discrepancy between the measured current impact flux and model predictions could be due to many issues, so craters <~50m diameter should not be used for crater age dating unless the uncertainties are understood. I find that these new martian craters are only slightly deeper on average than the expected depth/diameter ratio (d/D) of ~0.2 for simple primaries; the majority would not be mistaken for secondaries based on d/D. A wide spread in d/D indicates that impact conditions or target properties might influence final crater morphologies at these sizes. Extended low-albedo features surround these new craters, presumed to have formed when the impact blast disturbed a surface coating of high-albedo dust, exposing a darker substrate. Some of these features changed drastically over a few Mars years, however, half of the sites show no changes at all. Estimated fading lifetimes cluster around ~7 Mars years. Controls on the amount and rates of fading have yet to be determined. These results show that the current impact production function is not under-sampling new impacts due to fading prior to detection. New craters have also been discovered on the Moon, using similar techniques. Five new impact craters were found that formed within the last ~40 years. Conclusions are unreliable with only these scant statistics, but preliminary comparisons indicate they follow the expected size frequency distribution predicted by the Neukum [1983; Neukum et al., 2001] production function and chronology. This also leads to a very preliminary measurement of the current Moon/Mars cratering ratio at a single diameter, which falls below models by only a factor of approximately six.

After studying modern architectural designs during my one-andone-half year residence in the United States, I have deepened my intellectual consciousness for Modern Chinese Architecture, a subject which I had previously researched through my studies in China. As a multi-national country, the United States has absorbed various foreign cultural systems, including the Chinese culture and its architecture. This has revealed itself in part through many unique "China-towns" such as those in New York, San Francisco, Chicago and other major metropolitan areas.Restricted by city planning and highway systems in the in the United States, the Chinese-like buildings in these American Chinatowns can not perfectly show the principles, philosophy and spirit of authentic Chinese architectural concepts. Rather, they are similar only on their facades by incorporating superficially reproduced symbols, responding to a pragmatic commercial need. This problem brings me to an unanswered question of how to present the Chinese concepts of space in modern architecture, and addresses the significant issues I have studied with my colleagues at the Beijing Institute of Architectural Design. After having worked both for S.O.M. in Chicago and at Ball State University I have made a new attempt to understand the philosophy and built forms of my homeland, based on this oneand-one-half year of study and new experience within western architectural design. Combining this older quest with my new experience became the focus of my thesis. / Department of Architecture

Thesis (M.F.A.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaf 24). / vi, 24 leaves, bound ill. (some col.), map 29 cm

Thesis (LL.M.). / Written for the Institute of Air and Space Law. Title from title page of PDF (viewed 2008/12/04). Includes bibliographical references.

Thesis (M.S.)--Missouri University of Science and Technology, 2009. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed May 13, 2009) Includes bibliographical references (p. 64-71).

Thesis (Ph.D.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 197-218.

This dissertation investigates the role of thermomechanical processes in the production of regolith on airless body surfaces. Thermally induced breakdown may provide a significant contribution to their surface evolution, by breaking down rocks and degrading craters. In Chapter 1, we use the traditional terrestrial methodology of evaluating the efficacy of this process by modeling the rate of surface temperature change (dT/dt) on various airless surfaces, using a damage threshold of 2 K/min. We find that the magnitude of dT/dt values is primarily controlled by sunrise/set durations on quickly rotating bodies, such as Vesta, and by distance to the sun on slowly rotating bodies, such as Mercury. The strongest rates of temperature change occur on slopes normal to the sun when a sunrise or sunset occurs, either naturally or because of daytime shadowing. We find, however, that high dT/dt values are not always correlated with high temperature gradients within the surface. This adds to the ambiguity of the poorly understood damage threshold, emphasizes the need further research on this topic that goes beyond the simple 2 K/min criterion. We further investigate this shortcoming in the terrestrial literature in Chapter two by modeling stresses induced by diurnal temperature variations at the mineral grain scale on these bodies. We find that the resulting stresses are controlled by mismatches in material properties between adjacent mineral grains. Peak stresses (on the order of 100s of MPa) are controlled by the coefficient of thermal expansion and Young's modulus of the mineral constituents, and the average stress within the microstructure is determined by relative volume of each mineral. Amplification of stresses occurs at surface-parallel boundaries between adjacent mineral grains and at the tips of pore spaces. We also find that microscopic spatial and temporal surface temperature gradients do not correlate with high stresses, making them inappropriate proxies for investigating microcrack propagation. Although these results provide strong evidence for the significance of thermomechanical processes, more work is needed to quantify crack propagation and rock breakdown rates in order to understand their overall contribution to surface evolution on these bodies. In Chapter 4, we investigate macroscopic scale effects on thermally induced stress fields in boulders of varying sizes and find that macroscopic thermal gradients may play a role in crack propagation within boulder interiors.

abstract: On Mars, sedimentary deposits reveal a complex history of water- and wind-related geologic processes. Central mounds – kilometer-scale stacks of sediment located within craters – occur across Mars, but the specific processes responsible for mound formation and subsequent modification are still uncertain. A survey of central mounds within large craters was conducted. Mound locations, mound offsets within their host craters, and relative mound heights were used to address various mound formation hypotheses. The results suggest that mound sediments once filled their host craters and were later eroded into the features observed today. Mounds offsets from the center of their host crater imply that wind caused the erosion of central mounds. An in depth study of a single central mound (Mt. Sharp within Gale crater) was also conducted. Thermal Emission Imaging System Visible Imaging Subsystem (THEMIS-VIS) mosaics in grayscale and false color were used to characterize the morphology and color variations in and around Gale crater. One result of this study is that dunes within Gale crater vary in false color composites from blue to purple, and that these color differences may be due to changes in dust cover, grain size, and/or composition. To further investigate dune fields on Mars, albedo variations at eight dune fields were studied based on the hypothesis that a dune’s ripple migration rate is correlated to its albedo. This study concluded that a dune’s minimum albedo does not have a simple correlation with its ripple migration rate. Instead, dust devils remove dust on slow-moving and immobile dunes, whereas saltating sand caused by strong winds removes dust on faster-moving dunes. On the Moon, explosive volcanic deposits within Oppenheimer crater that were emplaced ballistically were investigated. Lunar Reconnaissance Orbiter (LRO) Diviner Radiometer mid-infrared data, LRO Camera images, and Chandrayaan-1 orbiter Moon Mineralogy Mapper near-infrared spectra were used to test the hypothesis that the pyroclastic deposits in Oppenheimer crater were emplaced via Vulcanian activity by constraining their composition and mineralogy. The mineralogy and iron-content of the pyroclastic deposits vary significantly (including examples of potentially very high iron compositions), which indicates variability in eruption style. These results suggest that localized lunar pyroclastic deposits may have a more complex origin and mode of emplacement than previously thought. / Dissertation/Thesis / Doctoral Dissertation Geological Sciences 2016

abstract: Impact cratering and volcanism are two fundamental processes that alter the surfaces of the terrestrial planets. Though well studied through laboratory experiments and terrestrial analogs, many questions remain regarding how these processes operate across the Solar System. Little is known about the formation of large impact basins (>300 km in diameter) and the degree to which they modify planetary surfaces. On the Moon, large impact basins dominate the terrain and are relatively well preserved. Because the lunar geologic timescale is largely derived from basin stratigraphic relations, it is crucial that we are able to identify and characterize materials emplaced as a result of the formation of the basins, such as light plains. Using high-resolution images under consistent illumination conditions and topography from the Lunar Reconnaissance Orbiter Camera (LROC), a new global map of light plains is presented at an unprecedented scale, revealing critical details of lunar stratigraphy and providing insight into the erosive power of large impacts. This work demonstrates that large basins significantly alter the lunar surface out to at least 4 radii from the rim, two times farther than previously thought. Further, the effect of pre-existing topography on the degradation of impact craters is unclear, despite their use in the age dating of surfaces. Crater measurements made over large regions of consistent coverage using LROC images and slopes derived from LROC topography show that pre-existing topography affects crater abundances and absolute model ages for craters up to at least 4 km in diameter. On Mars, small volcanic edifices can provide valuable insight into the evolution of the crust and interior, but a lack of superposed craters and heavy mantling by dust make them difficult to age date. On Earth, morphometry can be used to determine the ages of cinder cone volcanoes in the absence of dated samples. Comparisons of high-resolution topography from the Context Imager (CTX) and a two-dimensional nonlinear diffusion model show that the forms observed on Mars could have been created through Earth-like processes, and with future work, it may be possible to derive an age estimate for these features in the absence of superposed craters or samples. / Dissertation/Thesis / Doctoral Dissertation Geological Sciences 2018

Submitted by Andre Amarante Luiz null (amarante@feg.unesp.br) on 2018-02-11T19:52:31Z No. of bitstreams: 1 A_Amarante__O_C_Winter__M_Tsuchida.pdf: 9049058 bytes, checksum: a87f695e2060e08b5657bf5c4106d282 (MD5) / Approved for entry into archive by Pamella Benevides Gonçalves null (pamella@feg.unesp.br) on 2018-02-14T10:49:37Z (GMT) No. of bitstreams: 1 amarante_a_dr_guara.pdf: 9049058 bytes, checksum: a87f695e2060e08b5657bf5c4106d282 (MD5) / Made available in DSpace on 2018-02-14T10:49:37Z (GMT). No. of bitstreams: 1 amarante_a_dr_guara.pdf: 9049058 bytes, checksum: a87f695e2060e08b5657bf5c4106d282 (MD5) Previous issue date: 2017-09-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A origem e estabilidade de satélites planetários estão, intimamente ligadas à origem do nosso Sistema Solar e à formação de planetas. Portanto, é apropriado estudar alguns casos peculiares para nossa compreensão atual sobre a formação do Sistema Solar e para entender a criação dos sistemas de satélites. Tendo isso em vista um estudo da estabilidade dos satélites internos de Urano é realizado procurando viabilizar um cenário estável para tal sistema. Nós encontramos um provável cenário que possa nos dar indícios de que o sistema de satélites internos de Urano possa ser estável. Outro cenário importante para compreender a formação de satélite é o estudo de nosso próprio satélite natural, a Lua. O estudo da origem a Lua é realizado através de uma rápida revisão bibliográfica das teorias de origem da Lua e com isso tentamos analisar qual seria o cenário mais provável de colisão dentro da teoria do Grande Impacto que favorece a formação do nosso satélite, levando em conta suas características físicas, químicas e petrológicas. O cenário mais provável foi aquele em que colisões com massas comparáveis são usadas para se originar a Lua. O estudo da estabilidade de coorbitais dos pequenos satélites do sistema binário Plutão-Caronte é importante visto que também é um caso de cenário de formação de satélites peculiares no Sistema Solar. O estudo dessa estabilidade nos levou a indícios de que o sistema não possui coorbitais à suas pequenas luas, fato comprovado até agora pela missão New Horizons. / The origin and stability of planetary satellites are closely linked to the origin of our Solar System and the formation of planets. Therefore, it is appropriate to study some peculiar cases to our current understanding of the formation of the Solar System and to understand the origin of satellite systems. In order to study the stability of the internal satellites of Uranus, in order to provide a stable scenario for such a system. We have found a probable scenario that allows the internal uranian system get stable. Another important scenario for the formation of satellites is the moon scenario. The study of the origin of the Moon is made through a revised bibliographical revision of the theories of origin of the Moon and with this we try to analyze which forming the most probable collision within the theory of Great Impact that favors a formation of our satellite, taking into account its physical, chemical and petrological characteristics. The most likely scenario was that collisions with comparable masses are used to originate the Moon. The study of coorbital stability of the small satellites of the Pluto-Charon binary system is important since it is also a case of a peculiar satellite formation scenario in Our Solar System. The study of stability has led us to evidence that the system is not coorbitary in its small moons, a fact proven so far by the New Horizons mission