TY - JOUR T1 - Age and origin of Late Quaternary eolianite, Kaiehu Point (Moomomi), Molokai, Hawaii JF - Journal of Coastal Research Y1 - 2005 A1 - Fletcher, C. H. A1 - Murray-Wallace, C. V. A1 - Glenn, C. R. A1 - Sherman, C. E. A1 - Popp, B. A1 - Hessler, A. KW - Amino acid racemization KW - aminostratigraphy KW - bermuda KW - carbonate lithofacies KW - cementation KW - cliche paleosols KW - eolianite KW - hawaii KW - island KW - Late Quaternary KW - limestone petrology KW - Marine KW - molokai KW - oahu KW - precipitation KW - sea level KW - sea-level KW - south-australia KW - Stable isotopes KW - stratigraphy AB - A well-preserved, vertically stacked succession of two genetically distinct eolianites and associated caliche paleosol units, capped by modern and Holocene coastal dunes, occurs at Kaiehu Point, west Molokai, Hawaii. The Pleistocene eolianite facies comprise well-cemented, medium grained skeletal carbonate sand and their morphostratigraphic context implies formation at times of lower than present sea level. Amino acid racernization (AAR) evidence suggests eolianite formation late in marine Oxygen Isotope Stage (OIS) 5, but lacks the precision to uniquely define in which isotopic substage the deposits formed. Coupled with the AAR results, the morphostratigraphic evidence, would suggest that the Lower Eolianite formed in OIS 5c and the Middle Eolianite during 5a with their superposed caliche paleosols having formed in subsequent stadial stages. The unconsolidated coastal sand dunes of Holocene age contain reworked Late Pleistocene skeletal carbonate sand based on AAR evidence. The most likely source of the reworked carbonate is from the erosion of the eolianites at Kaiehu Point. The Pleistocene eolianite-caliche paleosol sediments reveal variable Mg-content, stable isotope ratios and petrological characteristics consistent with changing degrees of weathering intensity and meteoric diagenesis. These changes are attributed to orographic effects resulting from relative sea-level changes. Accordingly, a two-phase model is favored for the formation of the eolianite-paleosol successions at Kaiehu Point, west Molokai. Eolianite sedimentation is initiated at times of marginally lower sea levels promoting the landward migration of bioclastic sand to form extensive eolian sandsheets. This is followed by a more pronounced phase of pedogenesis associated with a further fall in sea level and concomitant increased rainfall due to enhanced orographic effects. VL - SI SN - 0749-0208 IS - 42 N1 - Sp. Iss. 42947fu Times Cited:3 Cited References Count:50 JO - J Coastal Res ER -