Post-Glacial Relative Sea-Level History of Oahua and Kauai

瓦华岛和考艾岛冰期后相对海平面历史

• 批准号: 9317328
• 负责人: Charles Fletcher
• 金额: $ 19.29万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-02-01 至 1998-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9317328&HistoricalAwards=false
• 关键词: Post; Glacial; Relative; Sea; Level

9317328 Fletcher An acceptable relative sea-level (RSL) history for the post- glacial period in Hawaii has not yet been proposed. Late Holocene RSL is characterized by gradually decreasing hydroisostatic uplift. New field evidence showing emergence documents the hydroisostatic deformation of Kauai, Oahu, Molokai, and probably Maui following the culmination of post-glacial RSL rise. The timing of initial emergence, its height, and it termination all appear to have an island-specific character reflecting the influence of island radius, distance from the volcanic center, and various site- specific factors. Research will focus on obtaining additional field data to constrain these variables and produce a model of hydroisostatic response along the Hawaii Ridge. Pleistocene and early Holocene RSL around Oahu and Kauai will be documented with cores from submerged shorelines. Wave-cut notches and drowned reef complexes indicate former sea-level positions at predictable depths encircling both islands. A small, hand-held pneumatic drill can sample early deposited carbonate dating former RSL. Petrographic and XRD analysis of samples will help define geologic history. Species-specific oxygen isotope contents will be determined from well preserved, dated coral samples. Variations in the oceanic oxygen isotope chemistry during the post-glacial transgression will be documented. The research will produce a detailed RSL history for Kauai and Oahu tied to changes in the stable isotope record of meltwater history.

9317328弗莱彻尚未提出夏威夷后冰川时期可接受的相对海平面历史。晚全新世RSL具有流体均衡抬升逐渐减弱的特征。新的现场证据表明，考艾岛、瓦胡岛、莫洛凯岛，可能还有毛伊岛在冰期后RSL上升达到顶峰后发生了水均衡变形。初始出现的时间、高度和终止似乎都具有岛屿特有的特征，反映了岛屿半径、离火山中心的距离和各种特定地点因素的影响。研究将集中于获得更多的现场数据，以约束这些变量，并产生沿夏威夷山脊的水均衡响应模型。瓦胡岛和考艾岛周围的更新世和全新世早期的RSL将被记录在水下海岸线的岩心中。波浪切割凹痕和淹没的礁石复合体表明，在两个岛屿周围可预测的深度，以前的海平面位置。一台小型的手持气动钻头可以对早期沉积的碳酸盐进行采样，确定前RSL的年代。样品的岩相学和X射线衍射分析将有助于确定地质历史。特定物种的氧同位素含量将从保存良好的年代确定的珊瑚样本中确定。冰川后海侵期间海洋氧同位素化学的变化将被记录下来。这项研究将产生考艾岛和瓦胡岛详细的RSL历史，与融水史的稳定同位素记录的变化有关。