UC San Diego

This study utilizes the geomorphology of guyots in the Louisville Seamount Chain to gain insight into the magmatic, erosional, and plate tectonic processes that have dominated the region. By studying the features that result from these complex processes, it becomes possible to hypothesize about how such edifices developed through time. While the majority of guyot studies have focused on the depth and nature of the transition from guyot summit plains to the flank slopes, this research takes advantage of high-resolution marine geophysical data to analyze the much smaller-scale features (peaks) that interrupt the otherwise flat guyot summit plains. Multibeam bathymetry, multichannel seismic reflection profiles, 3.5 kHz profiles, and numerous dredge samples were collected during a 2006 site survey cruise to the Louisville Seamount Chain in the Southwest Pacific Ocean. All of these sources of geologic information were used in combination to make observations about the morphology and composition of the guyot summit plain peaks found in the chain. Then, by comparing these features with landforms already well-established in scientific literature, it becomes possible to postulate the specific origin of each individual peak. The four mechanisms of peak formation identified in this study are: constructional volcanic processes, erosional residuals, tectonic deformation, and biogenic carbonate-reef growth. The spatial and temporal relationships among these different origins of guyot summit plain peaks can then be evaluated in order to draw conclusions about the evolution of the seamount chain as a whole