(Table 1) Biogenic opal concentrations for a latitudinal transect of seven ODP Leg 167 sites along the California margin

Ocean Drilling Program Leg 167 drilled thirteen sites in a series of depth and latitudinal transects along the climatically sensitive California margin to reconstruct the Neogene history of deep-, intermediate-, and surface-ocean circulation changes (Lyle, Koizumi, Richter, et al., 1997, doi:10.2973/odp.proc.ir.167.1997). Significant variations occurred in sediment properties on all time scales as seen in the high-resolution nondestructive shipboard measurements (e.g., bulk density and color reflectance), high- to intermediate-resolution downhole log measurements (e.g., resistivity and magnetic susceptibility), and lower resolution discrete shipboard measurements (e.g., physical properties and carbon geochemistry). Thus, these Leg 167 sites provide an opportunity to address paleoceanographic questions about the evolution of the California Current and links between the equatorial Pacific and the high-latitude North Pacific from millennial and orbital to tectonic time scales. This data report presents the results of biogenic opal analyses from a latitudinal transect of seven sites along the California margin for the time interval from 8 Ma to the present. Site selection for opal analyses was based upon such parameters as opal content, stratigraphic continuity, and lack of coring disturbance.

大洋钻探计划（Ocean Drilling Program, ODP）第167航次（Leg 167）在气候敏感的加利福尼亚陆缘沿深度与纬度断面布设了13个钻探站位，旨在重建深海、中层及表层大洋环流变化的新近纪（Neogene）历史（Lyle、Koizumi、Richiter等，1997，doi:10.2973/odp.proc.ir.167.1997）。通过高分辨率无损船基测量（如体积密度、颜色反射率）、中高分辨率井下测井测量（如电阻率、磁化率）以及低分辨率离散船基测量（如物理属性与碳地球化学）均可观察到，沉积物属性在所有时间尺度上均存在显著变化。因此，该航次的这些站位为解答古海洋学（paleoceanography）相关问题提供了契机，包括加利福尼亚海流（California Current）的演化，以及赤道太平洋与北太平洋高纬度区域之间的联系，研究尺度覆盖千年尺度、轨道尺度至构造尺度。本数据报告呈现了沿加利福尼亚陆缘7个站位的纬度断面在8百万年至现代的时间区间内的生物成因蛋白石（biogenic opal）分析结果。蛋白石分析的站位选取基于蛋白石含量、地层连续性以及无取芯扰动等参数。