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目前世界上最富的一些砂金矿床,尽管其形成时的气候条件各异,但许多都产于寒冷地区.由此看来,在风化过程中冰冻气候与金的区域化学性质之间很可能存在着某种重要的联系.这一设想以及北极砂砾层及土壤砂金中金以自然金形式产出这一有争议的问题,促使我重新考虑金在低温下的地球化学现象.可能影响天然含金岩石风化的几个因素,金的化学络合作用及其后来的运移和沉积作用都与冰冻作用密切相关.在岩石和土壤的冻结过程中,残留在颗粒表面的未冻结的薄层吸附水膜,由于冰体析出的溶解物、气体及微粒,加剧了对岩石和土壤矿物成分的溶蚀.阳离子(优于阴离子)从不断生长的冰晶体中优先折出,在冻结土壤中引起正负电荷分离,以及在水-冰界面上出现可测出的电流流动.这种现象致使埋在土壤中的管道发生棘手的季节性电解溶蚀现象;在地质时期这一现象亦可导致象金这样常态下难溶金属发生溶蚀.在矿物表面的粘土、有机酸、细菌及其它有机物等冰成堆积亦可在附近提供为阳离子键位交换的空穴,从而加速化学反应,使游离阳离子迅速从溶液中运移出来.这种机理可能控制金的溶解和再沉淀.这些物理、化学及电学因素都有益于岩石的溶解(除霜冻破碎之外),有助于金及其它贵金属的溶解、运移以及再沉淀,因而在很大程度上势必影响金在低温条件下的特性.大量砂金矿床之所以出现在加拿大北部、阿拉斯加和西伯利亚地区,一定程度上归咎于这些地区的低温环境.
At present, some of the richest deposits in the world are likely to occur in cold regions despite the different climatic conditions at the time of their formation, and thus it is likely that there will be a possibility of regional chemistry between the frozen climate and gold during the weathering process An important link between this assumption and the controversial issue of gold being produced as natural gold in gravel and soil gold in the Arctic prompted me to reconsider the geochemistry of gold at low temperatures that could affect natural gold Several factors of rock weathering, chemical complexation of gold and its subsequent migration and sedimentation are closely related to the effect of freezing. During the freezing of rock and soil, the un-frozen thin layer of adsorbed water remaining on the surface of the particles Membranes, which dissolve rocks and soil mineral components due to dissolution of dissolved matter, gases and particulates from ice bodies, give priority to the growing ice crystals, giving rise to positive and negative charges in the frozen soil Separation, and measurable current flow at the water-ice interface, a phenomenon that causes tricky seasonal electrolytic corrosion of the pipe buried in the soil. During the geological period Like the gold can also lead to the dissolution of insoluble metals in the normal state.On the mineral surface of the clay, organic acids, bacteria and other organic matter ice accumulation can also be provided in the vicinity of the cation-exchange holes, thus accelerating the chemical reaction , Allowing free cations to quickly migrate out of solution, a mechanism that may control the dissolution and reprecipitation of gold.These physical, chemical, and electrical factors all contribute to the dissolution of rocks (except frost crushing), contribute to gold and The dissolution, migration and reprecipitation of other precious metals, to a large extent therefore, are bound to affect the properties of gold at low temperatures.A large amount of placer gold deposits are found in northern Canada, Alaska and Siberia, due to some extent to these regions Low temperature environment.