The Next-Generation Attenuation (NGA) projects provide uniformly-processed ground motion data from earthquakes recorded in different tectonic settings and regions around the world. Since 2008, three separate NGA projects have been developed: NGA-West and NGA-West2 for shallow crustal earthquakes in active tectonic regions like California; and NGA-East for stable continental regions like central and eastern North America. Currently, the NGA-Subduction project is under development, focusing on gathering data for regions affected by subduction-zone earthquakes like the Pacific Northwest (PNW) and Alaska regions of North America, Japan, Taiwan, Mexico, and South America, among other areas.

As part of the effort of assembling and characterizing the ground motion dataset for South America, this thesis describes the development of a Chilean ground motion database for the NGA-Subduction project. First, the tectonics and seismicity of South America are discussed to highlight the importance of these subduction-zone earthquakes, with a particular emphasis on Chilean events. Subsequently, an overview of the seismic data providers in Chile is presented, describing the evolution of the different institutions and seismic networks that have recorded ground motions in the country. In addition, prior works on ground motion datasets and ground motion modeling for South America and Chile are introduced and briefly described. The importance of regional considerations in the development of global models, particularly with respect to path terms, is emphasized by comparing attenuation features observed in past work on the 2010 M 8.8 Maule Chile and M 9.0 Tohoku Japan events.

A significant effort was made to collect and characterize required metadata to accompany the ground motion database, including source, path, and site information. This thesis is primarily focused on presenting the development of parameters describing seismic sources. To date, the NGA-Subduction event catalog for the South American region consists of 826 earthquakes that extend from 1985 to 2016, 689 of which have been recorded in Chilean territory. The moment magnitude ranges from M 2.5 to M 8.8. In terms of number of recordings, the data obtained in Chile (4,213 time histories) represents approximately 68% of the total dataset in South America. The event database is controlled by interface and instraslab earthquakes, having 404 and 223 events respectively, with considerably fewer shallow crustal and outer-rise events. When possible, seismic sources are defined using suitable finite fault models (FFM) from the literature. Processes are introduced here to interpret published FFMs in a way that the most salient portion of the fault plane is used for site-to-source distance calculations. These processes improve upon those that had been used previously and have been adopted elsewhere in the NGA-Subduction project (e.g., Japan). In the case of the events without available FFMs, source characterization is similar to that used previously in NGA-projects.

Path and site parameters are currently being characterized and preliminary results are briefly explained in the final chapter. The results presented in this thesis regarding source information, along with the results from path and site characterization, will be part of a data PEER report describing the Chilean dataset.

For engineering design and seismic risk assessments, earthquake ground motions are characterized using intensity measures such as peak acceleration or spectral accelerations. Ground motion models (GMMs) estimate statistical distribution of intensity measures given information about the source, source-site path (distance), and site condition. This research pertains to data resources used to develop GMMs for subduction zone regions and adapts a global GMMs to a target region. My initial research developed portions of the NGA-Subduction (NGA-Sub) project database. I worked with other experts to characterize seismic sources and source-to-site paths. The database contains data from 1,880 earthquakes in Alaska, Cascadia, Central America and Mexico, Japan, New Zealand, South America, and Taiwan. Source parameters are related to the earthquake focus and finite fault representations. An important issue was the assignment of event types (intraslab and interface). I developed event type classification procedures that consider hypocenter locations relative to the interface, focal mechanisms, and other factors. The second phase of research involved collaborating with researchers in Mexico to enhance data resources for that region (relative to NGA-Sub) and to use the information to develop a regionally customized GMM. I selected Mexico because it has high seismic hazard, its available GMMs have deficiencies, and it has substantial data from recent events that were not considered in NGA-Sub. The database for Mexico is extended by considering small magnitude (M < 6) events and three large events (M 7.2-8.3) in 2017 and 2018. The latter are particularly important, because they are well recorded over a broad distance range and apply for hazard-critical conditions. These changes increase the size of the database from 593 recordings from 66 events (NGA-Sub) to 1882 recordings from 121 events. These data are examined relative to a global NGA-Sub model, which reveals a number of interesting features including faster anelastic attenuation in backarc than forearc regions and generally similar levels of site response as in the global GMM. A novel model for site response in Mexico City is proposed that is properly centered with respect to GMMs and that accounts for the unique Lake Texcoco geology.

A bioinformatic characterization of the KX Blood- Group Antigen (KXA) Family has been conducted. This family includes the XK-related protein 8 which has recently been shown to function as a phospholipid flippase (Suzuki et al, 2013). This however, may not be its primary function. Multiple alignments, phylogenetic trees, and sequence analyses allowed me to characterize the KXA Family, revealing 17 primary clusters. Also, using average hydropathy, amphipathicity, and similarity plots, I was able to show that the members of this family possess on average 9 transmembrane helices (TMSs). Although, previous work has mostly been done with animal proteins, I demonstrate that homologs can be found in plants and ciliates. Furthermore, I show that the KXA family is a member of an established superfamily (TOG) of proteins having transport, light reception, electron flow, and G-protein receptor functions.