Computerized Forecast of Laterite-Bauxites of Plateau and Peneplain Type [antikvár]

1. AN OÜTLINE OF THE AGGREGATE BAUXITÉ RESOURCES OF THE WORLD In terms of the surveys and estimates prepared in the early 1980's the Earth's bauxité resources are estimated (V. G. HlLL-S. OSTOJlé, 1981) to amount to about 140 thousand millión MT, of which about 9 thousand millión MT are karstic bauxites. The commercial bauxité reserves in a more strict sense (bauxites suitable for industrial use) are much less than that figure. As estimated most recently by GY. BÁRDOSSY (1987), the Earth's bauxité reserves are about 54.0 thousand millión MT, of which 47.5 thousand millión MT are lateritic bauxites, 6,2 thousand millión MT karstic bauxites and 0.3 thousand millión MT bauxites of the so-called Tyhvin type. LOTZE's estimate (1978) in the same classification gives 32 thousand millión MT of lateritic bauxité and 6.7 thousand millión MT of karstic bauxité. According to the survey carried out by E. Szabó in 1987, the Earth's probable bauxité resources amount to 60.5 thousand millión MT, of which 54.1 thousand millión MT are lateritic bauxites, 6 thousand millión MT are karstic bauxites and 0.4 thousand millión MT are bauxites of Tyhvin type. As evident from the above list of estimates made with a time span of ten years, there is a rather wide scatter in the figures listed. In fact, there are estimates sűggesting even greater extreme values. So, for example, Tenyakov places at about 200 thousand millión MT the upper limit of the potential bauxité resources. For a comparison according to authors, the major individual reserve estimates are given in Fig. 1. The Earth's bauxité resources are dominated, undoubtedly by the lateritic bauxites with an estimated 25-186 thousand millión MT of resources, the lateritic versus karstic bauxites ratio varying between 5:1 and 16:1. The quantitative differences in the resource estimates are basically due to the very high degree of uncertainty primarily in the case of the lateritic bauxité resources, for these, though most of them occur scarcely buried, almost completely exposed on plateaus (about 80%), are, in somé allegedly prospective regions (mainly the intertropical areas of the developing countries) still fully unknown or, for that matter, merely surmised. On account of this, the conclusion may be drawn that the lateritic bauxites of the Earth and primarily the lateritic bauxites of plateau type are that which may turn out to have a surprise in store as far as the real assessment of the reserves is concerned. The standard deviation in this case may account for about 60-70% of the currently estimated maximum of the global bauxité resources. Not until the decades that followed the Second World War did a real upswing in the complex scientific research and mineral exploration aimed at eliminating the uncertainty