浦东新区“硬土层”的沉积物特征和成因

在浦东新区高层建筑主要桩基持力层之一的暗绿色和褐黄色硬土层系统勘察的基础上,运用沉积学的研究方法和地层对比研究,对硬土层的沉积特征作一剖析。认为该硬土层为末次冰期干冷气候条件下风成黄土沉积物经过次生变化作用演变而成。

The Sedimentary Features and Origin of the Stiff clayin Pudong new area, Shanghai

The top strata of the late Pleistocene series in Puclong, Shanghai generally consist of dark -green or buownish -yellow stigb clay with a thickness of up to 2 - 10 meters, which is covered by Holocene transgression sediments with the thickness about from 20 to 30 meters. Based on the analysis of core-drill samples from Pudong, Shanghai on grain size, heavy minerals, clay minerals, microfauna, pollen and spores, geochemical analyses, SEMs, and C dates, the stigb clay corresponds with.the Xiashu loess on the hilly areas of the westeun Yangtze River Delta, the sedimentary features and origin of the stigb clay is discussed in this paper. It is suggested that the stigb clay is aeolian loess in origin, deposited under dry-cold climatic conditions during thd last glacial period.