Glacial chronology of Mauna Kea, Hawaii, as constrained by surface- exposure dating

Since S.C.Porter completed his study of the glaciation of Mauna Kea, Hawaii, new surface-exposure dating techniques have been developed to estimate ages of Quaternary glacial events. Our rock varnish, cosmogenic ³⁶Cl buildup, ¹⁴C dating of organics in silica skins, and in situ ¹⁴C results affirm Porter's glacial sequence. The Makanaka Glaciation lasted from ~40 ka to ~13 ka, but glacial retreat begun by ~18 ka was almost complete by ~15 ka. We place the Waihu Glaciation during the early Wisconsin (oxygen-isotope stage 4) based on exposure ages of ~60 to 70 ka, and the Pohakuloa Glaciation in oxygen-isotope stage 6 based on exposure ages of >132 to 163 ka. -from Authors