南极纳尔逊冰缘沉积物元素地球化学特征及其化学风化作用研究

本文对西南极地区纳尔逊冰盖边缘N1沉积序列化学元素组成特征和风化作用地球化学过程进行了研究。结果表明:N1沉积序列中元素的组成与该地区玄武质火山岩的化学组成具有密切的关系,该序列沉积物是自然环境下风化的产物,因此本文分析样品元素的平均含量可以作为该地区冰缘沉积物的背景值;冰缘沉积物所记录的源区化学风化作用强度显得非常微弱,处于脱Ca、Mg、Na早期风化阶段,碎屑矿物的风化过程多处在蒙脱石阶段;沉积序列中元素的活动强度及其比值变化,反映了局部的风化作用强度不同和气候环境的变化。上述研究结果有助于进一步研究南极冰缘环境的演变

GEOCHEMISTRY AND CHEMICAL WEATHERING OF NELSON PERIGLACIAL SEDIMENTS, ANTARCTICA

Geochemical characteristics and chemical weathering of periglacial sediments on the edge of Nelson Ice Cape, Antarctica were studied in a profile. The results show that the periglacial sediments have a close genetic relation to basalt volcanic rocks there. It can be deduced from the analyses of major elements of the periglacial sediments that their source rocks should be at a weak weathering stage, i.e ., the stage of de-Ca (decalcification), de-Mg and de-Na. The chemical weathering of detrital minerals is at the montmorillonite stage.