Weathering residuum

The very thick and electrically highly conductive weathering residuum in Australia limited the use of conventional geochemical techniques. Nevertheless, the Elura Zn-Pb-Ag massive sulfide body in New South Wales showed trace element, and conductance patterns in the A and B horizon soils over more than 100m of overburden similar to those found in Canada (Govett etal. 1984). 

Asphalt Manufacture Saleable asphalts are produced from the residua of selected crudes. The residuum itself may be sold as straight reduced cuts to make it easier to handle, producing the so called cut-back asphalts. Another variation is air blown or oxidized asphalts for improved tenacity, greater resistance to weathering, and decreased brittleness. Emulsified asphalts are made for application at relatively low temperatures. 

The final case of surficial ore genesis dealt with here involves the transport of physically disaggregated residuum from physically and chemically weathered materials by wind and water, resulting in placers, mineral deposits formed at the Earth s surface by mechanical... 

The combined influences of solubilization, evaporation, and oxidation are known as weathering. Weathering preferentially removes the lighter hydrocarbon fractions, leaving a residual material made up of relatively heavy hydrocarbons. Over the shorter term in aquatic environments, this residuum forms a stable water-in-oil emulsion known as mousse, which is the material that usually impacts shorelines after an offshore spill. The mousse combines with sediment particles on the shore to form sticky patties of oil and sand, which eventually form asphaltic lumps. 

At sea, weathering of the mousse eventually results in the formation of a dense, semi-solid, asphaltic residuum known as tar balls. In the vicinity of frequently traveled tanker routes worldwide, tar balls can be commonly found floating offshore and on beaches. Tar balls are especially common in places where the oceanic cir-... 

During igneous phosphate rock weathering, a wide variety of secondary phosphate minerals and clays may form. These phosphate minerals and clays indiide all the minerals previously mentioned in conjunction vwth sedimentary deposits. The residuum over such deposits is typically very rich in iron and contains significant proportions of hematite and goethite. 

Blends of residuum waxeSf uncombined fats, rosin oils, and pitches. This group is particularly suited to the lubrication of rock bits, steel cables, water pumps, dredges and chains, and gears operating under water or imder exposed weather conditions. 

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