海洋地质与第四纪地质

利用²¹⁰Pb同位素地质学技术测定了我国南海,南黄海和渤海26个岩心现代沉积速率和沉积通量。发现采样点岩心中²¹⁰Pb的放射性强度随深度衰减呈现出五种垂直分布模式,利用其分布模式,分析研究了采样点海区沉积作用强度、物质来源和沉积环境。²¹⁰Pb资料表明我国陆架浅海采样点、尤其象黄河三角洲高速沉积区近百年来的沉积速率和沉积格局有显著的差异和独特的沉积特征。

Based on 210Pb method, sedimentation rates and fluxes of 26 cores ,collected from the South China Sea, South Huanghai Sea and Bohai Sea have been determined. Profiles of 210Pb in the cores show that the distribution of 210Pb activity, decaying with depth, has five models. Most of the profiles of 210Pb in the South China Sea and in the South Huanghai Sea appear as a two-segment model, some of them appear as a three-segment model, only that in core Kc-10 appears as a one-segment model, but in the Bohai Sea the profiles of 210Pb show stage and invert models. 210Pb data indicated that they showed the sedimentary environment and "history event" record well. The apparent 210Pb sedimentation rates and fluxes are 0.19-0.47 cm/a and 0.26-0.51 g/cm2. a in the South China Sea, 0.094-0.69 cm/a and 0.067-0.78 g/cm2. a in the South Huanghai Sea, and 0.068-14.52 cm/a and 0.082-14.87 g/cm2. a in the Bohai Sea, respectively. In addition, using the model of 210Pb profiles, the sedimentation intensity, material sources and sedimentary environment in the coring area have been studied.