Physical Sciences and Mathematics Commons^™

Clay Mineral Characterization And Production In Impact Settings: A Case Study On The Chicxulub Impact Structure, Mexico, Sarah L. Simpson

Electronic Thesis and Dissertation Repository

Impact cratering is the most ubiquitous geologic process shaping the surface of solid bodies in our Solar System. Despite their deleterious effects, impacts have the potential to initiate transient hydrothermal systems, making them attractive targets in the search for water and extraterrestrial life. The relatively low temperature nature of these environments and poor preservation state of craters on Earth leads to difficulties in determining the provenance of many alteration phases, particularly clay minerals. This becomes especially problematic on other clay-rich planetary bodies (e.g., Mars) where limited geologic information can lead to ambiguous and/or inaccurate interpretations. This thesis presents a case …

Impact Cratering Processes On The Earth And Moon: Meteorites, Complex Craters, And The Origin Of The Moon, Patrick Hill

Electronic Thesis and Dissertation Repository

This thesis seeks to understand the mechanism of hypervelocity impacts, lunar origin and geology, and stable isotope techniques and its application to lunar material. Three lunar regolith breccias, Dhofar 1673, Dhofar 1983, and Dhofar 1984, were examined. The petrography, mineralogy, isotope chemistry, and bulk chemistry of these meteorites were quantified to investigate their origin. The chemistry of the impact melt rock and bulk chemical analysis suggests sourcing from either the Feldspathic or Outer Feldspathic Highland Terranes. Given the similarities in the meteorites, and the proximal location of each find (within 500 m), this thesis proposes strong evidence for their pairing. …

Morphologic Mapping Of Lunar Impact Basins, Zachary R. Morse

Electronic Thesis and Dissertation Repository

Modern high-resolution remote sensing datasets for the Moon provide a detailed view of the lunar surface and its features. This thesis uses visible, compositional, and topographic data to create the most detailed geomorphological maps to date of portions of three lunar impact structures: Orientale Basin, Tsiolkovsky Crater, and Schrödinger Basin, which are three of the best-preserved impact structures on the lunar farside.

This thesis discusses the mapping and analysis of seven distinct ejecta facies around Orientale, nine distinct facies in and around Tsiolkovsky, and twelve units of surface materials in the central Schrödinger Basin region. This analysis utilized 100 m/pixel …

Impact Craters On Titan: Finalizing Titan's Crater Population, Joshua E. Hedgepeth

Electronic Thesis and Dissertation Repository

Titan is one of the most dynamic moons in the solar system. It is smaller than Earth and much colder, yet Titan is eerily similar to Earth, with rivers, rain, and seas, as well as sand seas that wrap around the equator. However, the rivers are made of hydrocarbons rather than water and the sand made of organics rather rock. We can use Titan’s impact craters to study how these processes modify the surface by comparing the craters depths, diameters and rim heights of Titan’s craters with fresh craters. Therefore, we have used the complete data set from NASA’s Cassini …

Stable Cu, Fe, And Ni Isotopic Systematics Of The Sudbury Offset Dikes And Associated Rocks, Peter Christoffersen

Electronic Thesis and Dissertation Repository

The stable isotope ratio compositions of Fe, Ni, and Cu (δ⁵⁶Fe, δ⁶⁰Ni, and δ⁶⁵Cu) are reported for the first time in rocks from the Sudbury Igneous Complex (SIC). Massive sulfide ores, Quartz Diorite (QD), Inclusion bearing Quartz Diorite (IQD), and rocks from members of the Main Mass of the SIC were analyzed. The objective was to better understand the origin(s) and source(s) of the Offset Dikes and the associated sulfide mineralization. Based on stable isotope ratios and petrographic observations, two distinct types of sulfide mineralization hosted within the Offset Dikes are identified. Massive sulfide …

Geophysical Study Of Complex Meteorite Impact Structures, William Zylberman

Electronic Thesis and Dissertation Repository

Hypervelocity impact craters are the most abundant morphologic features on rocky planetary bodies of the Solar System, except on Earth where they have mostly been erased by plate tectonics, erosion, or are buried under sediments. The internal structure of complex impact craters can only be studied on Earth by using ground-truth geophysical and geological studies. Such approaches - combined with modeling - can reveal how impact cratering, target geological composition, erosion and other post-impact processes can lead to the observed geophysical anomalies, which could also be detected by remote geophysical data on other planetary surfaces. In this work, a multidisciplinary …

The Sudbury Impact Structure - New Insights Into The Origin And Emplacement Of The Basal Onaping Intrusion And The Parkin, Trill And Foy Offset Dykes Of The North Range, Denise Anders

Electronic Thesis and Dissertation Repository

The 1.85 Ga Sudbury impact structure is considered a remnant of a multi-ring basin with an estimated original diameter of 150-200 km. The so-called “Basal Onaping Intrusion” form discontinuous sheets between the Granophyre of the Sudbury Igneous Complex (SIC) and the Sandcherry Member of the Onaping Formation and had been considered part of the complex breccia series of the Onaping Formation. Based on the investigation of core and field samples from the North Range we conclude that the Basal Onaping Intrusion, in fact, are the roof rocks of the SIC and, thus, may represent the initial bulk composition of the …

A Multispectral Assessment Of Complex Impact Craters On The Lunar Farside, Bhairavi Shankar

Electronic Thesis and Dissertation Repository

Hypervelocity collisions of asteroids onto planetary bodies have catastrophic effects on the target rocks through the process of shock metamorphism. The resulting features, impact craters, are circular depressions with a sharp rim surrounded by an ejecta blanket of variably shocked rocks. With increasing impact energy, the inner crater cavity can preserve complex morphologies including terraced walls, central uplifts, and melted rocks. The lack of erosion due to the absence of water or an atmosphere makes the Moon the perfect target to study impact crater processes, in particular the distribution of highly shocked materials within impact craters of different sizes. …