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元素富集剖面图只对四个前寒武纪古土壤(二个发育于玄武岩,二个发育于花岗闪长岩上)进行解释。所有四个古土壤似乎都是原始的厚层腐泥表土土壤侵蚀残余。花岗质的古土壤发育于南非,它们下伏为29—30亿年的蓬戈拉超群(Pongola)和28—29亿年多米尼矿层(Dominion Reef)砾岩。玄武岩的古土壤,其中之一也出现于南非,它覆于文泰尔斯多尔(Ventersdorp)玄武岩之上,下伏为23亿年黑矿层石英岩;另一个玄武岩古土壤下伏加拿大地盾阿比提比带蒂米斯卡明(Timiskaming)群的27亿年砂岩。所有四个古土壤显示出向上钠流失,但重碱元素铷和铯的流失不一致。铁在富铁玄武岩母岩,向上有所减少,但在贫铁花岗质母岩,向上铁流失不一致。稀土元素比强烈现代风化期间为少。铀部分是从钍中分离,可能是由于前寒武纪风化作用期间氧化溶解的结果。
Elemental enrichment profiles explain only four Precambrian paleosols (two on basalts and two on granodiorites). All four paleo-soils appear to be remnants of the original thick-seated topsoil soil erosion. The granitic, ancient soils, which develop in South Africa, underge two to three to three billion years of Pongola and 2.8 to 2.9 billion years of conglomerate dominance in the Dominion Reef. The ancient soils of basalts, one of which is also found in South Africa, overlie the basalt of Ventersdorp, underlying 2.3 billion years of black-ore quartzite; the other basalt, More than 2.7 billion years of sandstone from the Timiskaming group in Bimbi. All four paleo-soils showed up-Na loss, but inconsistent loss of heavy-alkali elements, rubidium and cesium. Iron in Fu iron basalt rock, up to reduce, but in poor iron granite parent rock, up iron loss inconsistent. Rare earth elements are less intense during modern weathering. Part of uranium is separated from thorium, probably due to the oxidation and dissolution during Precambrian weathering.