Abstract: System and method for estimating a spatial distribution of a characteristic associated with Earth resources. The method includes receiving at an interface palaeogeography data including (1) palaeotopography data, (2) palaeobathymetry data, (3) and a palaeo-earth systems model; calculating with a processor, a retrodictive model of the characteristic based on the (1) palaeotopography data, (2) the palaeobathymetry data, and (3) the palaeo-earth systems model; and imaging the spatial distribution of the characteristic over a part of the Earth.

Abstract: System and method for estimating a spatial distribution of a characteristic associated with Earth resources. The method includes receiving at an interface palaeogeography data including (1) palaeotopography data, (2) palaeobathymetry data, (3) and a palaeo-earth systems model; calculating with a processor, a retrodictive model of the characteristic based on the (1) palaeotopography data, (2) the palaeobathymetry data, and (3) the palaeo-earth systems model; and imaging the spatial distribution of the characteristic over a part of the Earth.

Abstract: A hydrometallurgical process for separating iron and nickel contained in iron and nickel-bearing sulphide materials, comprising selective leaching of iron with respect to nickel with hydrochloric or other mineral acid to provide a leach solution and leached solids. The nickel contained in the leach solution is separated from the dissolved iron as nickel sulphide by precipitation with hydrogen sulphide in the presence of an iron-bearing substance in which the iron is present in a form selected from the group comprising oxides, hydroxides and combinations thereof.

Abstract: An improved method for agglomerative fluid bed roasting of metal sulphide particles. The sulphide particles are fed as an aqueous slurry through the freeboard of the roaster onto the surface of a bed of roasted calcine agglomerate particles fluidized by a free oxygen-bearing gas. Slurry water is evaporated in the bed and the sulphides are roasted therein. The feed rates of sulphide, water and free oxygen-containing gas are controlled to ensure temperatures in the roaster such that fusion occurs during roasting and agglomerated calcine particles are formed with regular, rounded surfaces. Calcine particles small enough to become entrained in the roaster off-gases are readily disengaged therefrom in cyclones to provide substantially dust-free SO.sub.2 -bearing gas. A preferred practice of the method is feeding substantially the stoichiometric amount of free oxygen to convert the sulphide to SO.sub.