A Multi?Hydrogeophysical Study of a Watershed at Kaiwi Coast (O?ahu, Hawai?i), using Seismic Ambient Noise Surface Wave Tomography and Self?Potential Data

We study a watershed containing an old stream valley at the Kaiwi Coast on O?ahu, Hawai?i. The site has undergone significant hydrogeological changes throughout its history, and present displays complex interactions of variety geological formations. highlight innovative efficient combination two hydrogeophysical methodologies for studying groundwater systems: ambient noise surface wave tomography (ANSWT), self-potential (SP) measurements. collected (1) 5 days continuous seismic data, using total 54 autonomous nodes, exploiting both ocean traffic sources (2) 386 SP measurements with average 20 m spacing, in same area. showcase how these data sets complement each other joint-interpretation framework. display distribution region, as well zones higher infiltration and/or flow rates. Using ANSWT, we identify structural contact between older Ko?olau basalt formation younger post-erosional Honolulu volcanics, sedimentary fill coastal deposits. joint interpretation clearly illustrates that occurs identified paleo-channels erosional basaltic bedrock. Furthermore, it highlights bedrock ridges likely forms important unit. Some may occur shallower material. Complementing enables us to place inferences, made from depth.