Physical Sciences and Mathematics Commons^™

Natural, Experimental, And Educational Explorations Of The Interiors Of Terrestrial Planetary Bodies, Nadine L. Grambling

Doctoral Dissertations

Planetary interiors are enigmatic, inaccessible, and vital to the processes that have formed the rocks we see on the surface of bodies in the inner Solar System today. Based on geophysical explorations of the Moon and Earth, along with information gleaned from rocks at the surface today, there is understanding of the basic structure and processes at depth. Using a combination of natural samples and experimental studies, we attempt to learn more about the physical conditions beneath the surface, and their effect on material properties and tectonics processes in the mantle.

On Earth, mid-ocean ridge processes have long been debated, …

Comparative Geochemical Analysis Of Recent Volcanic Flows On Barva Volcano, Costa Rica, Julie Coulombe

Masters Theses

ABSTRACT

Barva Volcano is a dormant stratovolcano in the Cordillera Central region of Costa Rica, rising above the capital city of San Jose with a population of 347,000. Barva’s recent inactivity and extensive forestation have resulted in fewer investigations of its composition, petrogenesis, and eruptive history. The objective of this research is to analyze the geochemical data from several of the most recent lava flows, evaluate variability between eruptive units, and ascertain physical conditions within the Barva magma storage region. The data collected in this study helps constrain the geochemistry of units seen in the quarry and provides information regarding …

Texture And Composition Of An Arid-Climate Weathering Profile And The Link Between Bedrock And Derived Sediment Composition, Kristan Leigh Watkins

Masters Theses

Multiple compositional aspects of Holocene, terrigenous-clastic sediment differ from its source, the underlying Cretaceous Stepladder granodiorite (Mojave Desert, California). Different processes can cause sediments to change in composition from source, including chemical weathering, hydrodynamic sorting during transport, and diagenesis. Sorting and physical processes have previously suggested. To assess the relative contributions of these processes to understand provenance reconstruction, the textures and compositions of an exposed Holocene saprolite weathering profile, grus, and granodiorite bedrock were studied. Fracture density in the weathering profile decreased from ~10% at the top to ~2% at the bottom of the profile in contact with the bedrock. …