The composition as well as shoreward zonation of facies suggests that the terrace represents an in situ fossil reef complex. Th U ages of in situ corals are all Pleistocene and suggest that the bulk of the feature formed during marine oxygen isotope stage 7. Deposition during these interglacial highstands has not previously been documented in the sea-level record on Oahu. Early shallow-marine diagenesis includes cementation by aragonite and Mg calcite in an active marine phreatic zone and predominantly micritization in a stagnant marine phreatic zone.
All limestones are now in an active marine phreatic zone.
The present seafloor is undergoing extensive biological and physical erosion. No Holocene limestones were recovered. Petrographic and geochemical signatures of subaerial exposure and meteoric diagenesis are recognized within the upper several centimeters of all cores. Thus, the present seafloor in the study area is a flooded Pleistocene subaerial exposure surface.