Downhole Logs as Paleoclimate Tools: A Case Study from Ocean Drilling Project Leg 128, Sea of Japan

井下测井作为古气候工具：日本海海洋钻探项目 128 段的案例研究

• 批准号: 9205744
• 负责人: Roger Anderson
• 金额: $ 12.5万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-11-01 至 1995-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9205744&HistoricalAwards=false
• 关键词: Downhole; Logs; Paleoclimate; Tools; Case

The primary goal of this proposal is to reconstruct continuous, quantitative biogenic and terrigenous deposition records from downhole logs and core data at ODP Site 798 on the Oki Ridge, Sea of Japan. We employ an innovative and efficient research strategy whereby continuous, multivariable log data are calibrated using "ground-truth" sediment lithological information obtained from cores. Site 798 was the Leg 128 target for a complete late Neogene paleoceanographic "reference" section for this climatically-important region; however, sporatic core recovery precludes a solely core-based reconstruction of these records below ca. 1 Myr. We describe separate core-based and log-based lines of research whose products will be merged to reconstruct sediment component percentage and flux records for the last 3 Myr. Discrete core sections are analyzed for biogenic opal, carbonate, organic carbon, and terrigenous percent using contiguous 30-cm "channel" samples which mimic log resolution. Ash layers provide accurate core-log depth correlations, and oxygen isotopic data are used to define glacial-interglacial stratigraphy, sedimentation rates, and phasing relationships. New computational techniques developed by Schlumberger-Doll Research are used to enhance the log resolution and sensitivity. These and other statistical techniques are used to quantitatively relate specific electrical, chemical, and physical log responses to the measured core lithological variations. The continuous percentage and flux records developed from this research provide us with an unique opportunity to: 1) Evaluate the utility of downhole logging methods to paleoclimate research, and 2) Understand the Pliocene-Pleistocene evolution of Japan Sea paleoceanography and paleoclimate within the context of other global climate records.

这项提案的主要目标是重建 连续定量的生物和陆源沉积 ODP 798现场的井下测井记录和岩心数据 日本海冲岐岭。 我们采用创新和高效的 研究策略，连续的，多变量的日志数据， 使用“地面实况”沉积物岩性信息进行校准 从核心中获得。 站点798是128航段的目标， 完整的晚第三纪古海洋学“参考”部分， 这个气候重要的地区;然而， 恢复排除了这些完全基于核心的重建， 下面的记录。100万 我们描述了单独的基于核心和基于日志的行， 研究其产品将被合并以重建沉积物 过去300万年的组分百分比和通量记录。 对离散的岩心切片进行生物蛋白石、碳酸盐、 有机碳和陆源百分比，使用连续30厘米 模拟对数分辨率的“通道”样本。 火山灰层提供了 准确的岩心-测井深度相关性和氧同位素数据 被用来定义冰川-间冰期地层学， 沉积速率和相位关系。 新 由Schlumberger-Doll Research开发的计算技术 用于提高测井分辨率和灵敏度。 这些 和其他统计技术被用来定量地 关联特定的电、化学和物理测井响应 测量的岩心岩性变化。 连续 从这项研究中得出的百分比和通量记录提供了 我们有一个独特的机会：1）评估的效用 利用井下测井方法进行古气候研究; 了解日本海上新世-更新世的演变 古海洋学和古气候的背景下， 全球气候记录。