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Reprinted with the permission of the Publishing House “Encyclopedia”.
including siderophile, chalcophile and lithophile elements (Figure 1). For this
purpose, we have attracted the data of distributions of the world resources of
mineral raw material during
the epochs of mineral formations (Bikhover, 1984);
rare and terrerare metals (Solodov, 1980); minerals resources of the World
Ocean (Аndreev et al., 1991) and also the newest data on the world reserves of
separate useful minerals, made by National department on mineral products of
the Ministry of ores and energy of Federal Republic of Brazil (Mineral
Summary, 2000) and Geological Services of USA (Minerals Yearbook, Metals
and Minerals, 2004). The data of the world reserves of separate useful minerals
given below is not quite authentic and correct, since it is summarized from some
separate publications. However, the comparison of reserves of some useful
minerals from various sources is showing that the sums of reserves is about of
the
same order, that testifies to sufficient objectivity of the data.
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In the tables and diagrams, presented below, the reserves of minerals are
given in weight quantities and relative percentages on the separate temporary
cycles and stages of geodynamic development of the Earth. In order to obtain
more objective picture of the distribution epochs of the maximal ore
generation of separate kinds of useful minerals, we have summarized the
quantity of extracted metals and stayed in bowels of the Earth the reserves
and resources of minerals on the time intervals
of formation ores deposits.
5. 1. S i d e r o p h i l e elements include iron, manganese, vanadium,
nickel, cobalt, chrome, platinum, diamonds, graphite and asbestos, the
reserves of which are represented on the Table 7 and Figure 3.
The analysis of data distribution reserves of iron testifies, that the most
favorable epoch of formation iron ores on the Earth was the permobile
geodynamic cycle in the interval 3,600-2,000 Ma, in which almost 85 %
reserves of iron and 93 % - of graphite are concentrated. The last data of
graphite evidences about the domination restorer
conditions on the surface
of our planet in that time. The reserves of manganese are distributed
diametrically to iron, in spite of geochemical affinity between them. The
reserves of manganese sharply prevail in newest continent-ocean cycle (200-
0 Ma), composing 84 %, whereas in permobile cycle its concentration was
about 16 %.
It is remarkable, that the distribution of reserves of nickel and cobalt
ores is similarly to manganese ores. So, the reserves of nickel and cobalt
ores in last cycle accordingly make 95% and 99% with account of huge
resources in iron -
manganese formations of oceans. On the continents
(without the amount of resources of these ores in oceans) the most
productive epochs to formation deposits of nickel and cobalt ores were,
accordingly, the permobile cycle in connection with greenstone belts (33 %
and 67 %) and last Mesozoic-Cenozoic cycle (67 % and 37 %). In all
probability, the favorable factors of accumulation of manganese, nickel and
cobalt in Mesozoic-Cenozoic epochs are the generation the oceans
connected to sharp expansion of the Earth, elevation of intermetalic mantle
and mafic magma to the surface, and also domination of oxygenous
conditions in the top geospheres of the planet.
The distribution of the reserves of chromic (86 %), platinum (74 %)
and vanadium (60 %) ores are genetically connected to the largest stratified
intrusions of ultrabasic and basic magmatites, that have well-defined early
Proterozoic maximum, dated to the early stage of protocontinental cycle.
The second less significant peak of reserves of chromic (10 %), platinum (7
%) and vanadium (18 %) ores is connected with late Caledonian stage of
geosynclinal cycle of the development.
The distribution of the revealed reserves of diamonds represents
practical and scientific interest, because it is genetically connected with
alkaline-ultrabasic
(kimberlite and lamproite) magmatites. The deposits of