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Core logs, scans, photographs, grain size, and radiocarbon data from coastal wetlands on the Hawaiian islands of Kaua`i, O`ahu, and Hawai`i

March 26, 2019

Over the past 200 years of written records, the Hawaiian Islands have experienced tens of tsunamis generated by earthquakes in the subduction zones of the Pacific "Ring of Fire" (for example, Alaska-Aleutian, Kuril-Kamchatka, Chile, and Japan). Mapping and dating anomalous beds of sand and silt along the coasts of these subduction zones are critical for assessing the hazard from distant as well as local tsunamis. This data release supports a study that reports on efforts to estimate future tsunami inundation through stratigraphic analyses of potential tsunami deposits beneath present and former Hawaiian wetlands, coastal lagoons, and river floodplains. Coastal wetland sites on the islands of Hawai'i, Maui, O'ahu, and Kaua'i were selected based on historical tsunami runup, numerical inundation modeling, proximity to sandy source sediments, degree of wetland disturbance, and breadth of prior geologic and archaeologic investigations. Marine-sourced sand beds within peaty and/or muddy wetland deposits on the north and northeastern shores of Kaua'i, O'ahu, and the Island of Hawai'i are interpreted as tsunami deposits. Core logs, Computed Tomography (CT) scans, photographs, radiocarbon age data, and sand bed data are presented here from three sites in addition to grain size data from one site on Kaua'i.