TARO:Temporal Analysis and Region Origin

This study aims to determine the origin, the recurrence rate, and the magnitude of ash-producing explosive eruptions. We focus on ash deposits in Ka‘ū, from Volcano to Na‘ālehu, as these areas are extensively mapped (Trusdell and Lockwood, 2019). We estimate the relative age of the ash deposits by the geologic principle of superposition, where younger rocks are deposited on top of older rocks.

We constructed stratigraphic columns of outcrops with lava flows of known ages to bound the ages of interbedded ash deposits. To determine if there is any relation between different ash deposits from different locations, we take samples of in situ ash to identify any unique characteristics like different colors, grain-size, and mineralogy. From the relationship between ash deposits spread across an area and the thicknesses of these deposits, we estimate the three-dimensional shape of each ash unit.

From the 3D shape, we model the probable direction from which an ash unit originated. From the 3D volume, we estimate the minimum magnitude of the explosive eruption that produced the ash. By utilizing field relationships, the extent and thickness of identifiable ash deposits, and GIS modeling, we can determine how often explosive eruptions occur in Hawai‘i, and the magnitude of those explosive eruptions.

https://www.usgs.gov/news/volcano-watch-chemical-analyses-shed-light-possible-origins-island-ash-deposits

USGS link provided, for more additional information on the TARO project and how it affects Hawaii Today in the futre.