To ensure the safety of the nation’s bridges, the National Bridge Inspection Standards (NBIS) require all bridges to undergo routine load rating analyses to assess their structural capacity. Accurate geometric information for each structure is necessary for load rating analyses. This information is typically ascertained from as-built plans. Still, when...
Large silicic magmatic systems are responsible for producing the largest explosive volcanic eruptions on earth. These phenomena, although infrequent (i.e., 1 per 100,000 years), impact the global climate, deposit ash over continent sized regions, and significantly alter landscapes. Silicic magmatism also plays important roles in the formation and ongoing evolution...
Successive sampling population size estimation (SS-PSE) is a method used by government agencies and aid organizations around the world to estimate the size of hidden populations using data from respondent-driven sampling (RDS) surveys. SS-PSE ad-dresses a specific need in estimation and helps us evaluate the vulnerability of areas to HIV...
Silicic caldera-forming eruptions are some of the largest and most destructive volcanic eruptions known, and present significant local and global hazards. The underlying processes within crustal magma plumbing systems that lead to the accumulation and eruption of large volumes of evolved magma remain enigmatic, yet there is broad consensus that...
Wood plays a key role in modern electrical infrastructure; crossarms and power poles utilize the high strength to weight ratio, availability and low cost of wood to facilitate the access of power to millions of Americans. However, wood presents a variety of challenges as a material. In structural applications, one...
Western Saudi Arabia hosts a number of young volcanic fields, known as “Harrats”. Harrats cover a significant proportion of western Saudi Arabia and are associated with significant volcanic hazards. However, the ultimate cause of volcanic activity remains unclear. Younger volcanism (<12 Ma) is clearly represented by the north-south-trending region known...
Cinder cones are useful geomorphic features for geological analysis because they generally have known initial states and follow a similar pattern of degradation as they are exposed to erosive processes. This is largely because cinder cones are produced by monogenetic eruptions. Characterizing large cinder cone fields in terms of age...
Natural durability remains one of the most attractive characteristics of wood, and helps wood obtain a premium price. A worldwide shift towards the use of younger trees from intensively managed forests has created greater concerns about wood quality, especially the wood’s resistance to fungi and insects. Wood durability is assessed...
The eruptive history of the Quaternary Cascades arc has been relatively well characterized. However, much less is known about the frequency and sizes of explosive eruptions produced by earlier stages of the arc. The Late Neogene Deschutes Formation of Central Oregon preserves a remarkable record of heightened pyroclastic activity during...
In volcanic systems, magma is generally stored in the shallow crust prior to eruption. The conditions of this storage directly impact whether the magma eventually erupts, or crystallizes within the crust to form a pluton. In this dissertation I present four studies that investigate the storage conditions of a number...