The exposed cross-section within this gulley shows the complex emplacement and erosional history associated with the Keanakako'i Formation. The green unit highlighted to the right consists primarily of the lower vitric unit. The red unit is primarily the upper, lithic unit, which was emplaced in a 1790 eruption. Note how the unit mapped as red drapes over the green unit and fills in the floor of a pre-existing gulley. Subsequent erosion, marked in blue, has reactivated this gulley and eroded through the red unit, resulting in a standing terrace against the far wall as well as several islands within the channel.
Image Number: WEB12887-2013
Credit: National Air and Space Museum, Smithsonian Institution
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