(Table 1) Sediment descriptions and age at DSDP Legs 5 and 63 Holes

Sediments from immediately above basalt basement and from between sections of basalt recovered from Deep Sea Drilling Project Legs 5 and 63 were analyzed by atomic absorption spectroscopy for Mg, Al, Si, Ca, Mn, Fe, Co, Ni, Cu, Zn, and Ba. All of these sediments showed enrichment in Fe and Mn over values typical of detritus supplied to the northeastern Pacific Ocean. X-ray diffractometry and differential chemical leaching indicate that up to 50% of the sediment, by weight, is in amorphous phases and that these phases are rich in Mn, Co, Cu, Ni, and Zn. Multivariate statistical analysis and normative partitioning of the chemical data indicate that much of the excess Fe and other transition elements in the sediment originate from hydrothermal sources.

对取自玄武岩基底正上方，以及深海钻探计划（Deep Sea Drilling Project）第5航次与第63航次所获玄武岩岩芯之间的沉积物样品，采用原子吸收光谱法（atomic absorption spectroscopy）对其中的镁（Mg）、铝（Al）、硅（Si）、钙（Ca）、锰（Mn）、铁（Fe）、钴（Co）、镍（Ni）、铜（Cu）、锌（Zn）及钡（Ba）进行了定量分析。所有受试沉积物的铁与锰含量，均高于输入至东北太平洋的典型陆源碎屑中的对应元素背景值。通过X射线衍射（X-ray diffractometry）与差示化学淋滤实验分析可知，该沉积物中按质量占比最高可达50%的组分为非晶质相，且此类非晶质相富含锰、钴、铜、镍与锌。对化学数据开展多元统计分析与规范分配计算后结果表明，沉积物中过剩的铁及其他过渡金属元素，大多来源于热液成因。