Opal contents at IODP U1417 (Gulf of Alaska) during Late Miocne to Early Pleistocene

International Ocean Discovery Program Site U1417 in the Surveyor (Gulf of Alaska) preserves the hemi-pelagic sediments influenced by the glacial and fluvi-al depositional from the Cordilleran Ice Sheet at the Chugach–St. Elias Mountains and Coast Ranges. A total of 441 samples covering the late Miocene to early Pleistocene were used to measure the biogenic opal content to trace the degree of diatom productivity in the surface water. In general, the biogenic opal content, fluctuating from less than 1% to a maximum of 48.6%, confirms the division of lithostratigraphic units and subunits: diatom-bearing clay-rich intervals vs clast-rich terrigenous intervals. The dataset presents Biogenic opal contents at U1417 from the Late Miocene to the Late Pleistocene, along with lithological units defined in the proceeding of IODP Expeition 341 (Jaeger et al., 2014). Biogenic opal contents at U1417 from the Late Miocene to the Late Pleistocene, along with lithological units defined in the proceeding of IODP Expeition 341 (Jaeger et al., 2014).

坐落于阿拉斯加湾勘测者海域的国际大洋发现计划（International Ocean Discovery Program，IODP）U1417站位，保存了受楚加奇-圣伊莱亚斯山脉及北美海岸山脉科迪勒拉冰盖的冰川与河流沉积作用影响的半远洋沉积物。本研究共获取覆盖晚中新世至早更新世的441件样品，通过测定其中的生物成因蛋白石（biogenic opal）含量，反演表层水体的硅藻生产力水平。总体而言，生物成因蛋白石含量介于不足1%至最高48.6%之间波动，该变化特征佐证了岩石地层单元及亚单元的划分：即含硅藻富黏土沉积段与富碎屑陆源沉积段。本数据集收录了U1417站位晚中新世至晚更新世的生物成因蛋白石含量数据，以及国际大洋发现计划341航次（IODP Expedition 341，Jaeger等，2014）报告中定义的岩石地层单元。