Physical Sciences and Mathematics Commons^™

Fan And Fracture Formation: Morphologic And Sedimentologic Characteristics Of Alluvial Fans On Earth And Mars, And Fracture Population Distributions On Europa, Claire A. Mondro

Doctoral Dissertations

Planetary science is inherently limited by the resolution and coverage of the currently available data. What can be observed in person, measured precisely in high-resolution data, or sampled for lab analysis in terrestrial investigations ca only be inferred, modeled, or hypothesized on other planetary bodies. The Earth remains our best tool for understanding the geologic systems of the rest of the Solar System. By applying what is known or can be measured about terrestrial systems, it is possible to determine how large-scale controls and observable features relate to geologic complexity that is beyond the resolution of planetary data. This dissertation …

Architectural-Element Analysis And Depositional Models For Pre-Vegetation Braidplain And Braid-Delta Environments, With Modern Analogues, Jason Gerhard Muhlbauer

Doctoral Dissertations

Pre-vegetation landscapes that blanketed the continents before the emergence vascular plants in the late-Silurian are proposed habitats for the earliest terrestrial biota and are analogous to martian setting thought to have potentially hosted life. Analysis of the middle member of the Wood Canyon Formation, a Cambrian age sandstone, reveal new details about terrestrial pre-vegetation environments. In fluvial middle-member stratigraphy, units are defined by stacking patterns of three facies associations (FA1-3). In FA1, stacked cosets, interpreted as braidplain barforms and channel fills, preserve vertical- and downstream-accretion elements under unimodal paleoflow. Floodplains, represented by FA2, include red-orange intervals of fine- to medium-grained …

Testing For The Effects Of Sediment Sorting On Detrital-Zircon Age Spectra By Sampling Multiple Bedforms In Single Fluvial Channels: Case Studies From The Wood Canyon Formation (Terreneuvian) And Stirling Quartzite (Ediacaran), Southeastern Ca, Jason Gerhard Muhlbauer

Masters Theses

Multiple bedforms were sampled from single fluvial channels in the Neoproterozoic (Ediacaran) upper member of the Stirling Quartzite and the Cambrian (Terreneuvian) middle member of the Wood Canyon Formation, southeastern California. Sampling strategy was designed to determine if sorting of detrital zircon populations by their textural properties can affect detrital-zircon age spectra in fluvial sandstones. Four samples derive from the middle member Wood Canyon Formation and two samples come from the upper member Stirling Quartzite. Sandstone samples vary in textural characteristics: grain sizes sampled range from fine to coarse sand, sorting ranges from moderately well to poorly sorted, and sampled …

Late Pleistocene And Holocene Hydroclimate Change In The Southeastern United States: Sedimentary, Pedogenic, And Stable Carbon Isotope Evidence In Tennessee River Floodplain Paleosols, James Joseph Kocis

Masters Theses

In order to understand hydroclimate variability of future climate change, it is important to know the timing and range of natural climate change in the past. The Southeastern United States (SE) is situated along the poleward extent of projected subtropical drying, where the expression of past hydrological balances remains unclear. The lack of high-resolution paleohydroclimate records in the SE forces climate modelers to base interpretations on better-understood regions of North America. The SE likely experienced significant changes in precipitation regimes resulting from its position at the convergence of several oceanic and continental air masses. To reconstruct precipitation variability, this study …

Constraining Martian Sedimentation Via Analysis Of Stratal Packaging, Intracrater Layered Deposits, Arabia Terra, Mars, Sarah Beth Cadieux

Masters Theses

Craters within Arabia Terra, Mars, contain hundreds of meters of layered strata

showing systematic alternation between slope- and cliff-forming units, suggesting either

rhythmic deposition of distinct lithologies or lithologies that experienced differential

cementation. Hypothesized origins of these intercrater layered deposits include

lacustrine, aeolian, volcanic airfall, and impact surge deposition. On Earth, rhythmically

deposited strata can be examined in terms of stratal packaging, wherein the interplay of

tectonics, sediment deposition, and change in base level results in predictable patterns

with respect to changes in the amount of space available for sediment accumulation.

Fundamental differences between tectonic regimes of Earth and Mars …