131
sedimentary and magmatic rocks in late Archean and early Proterozoic (Figure
2) (Crustal..,1974). The process of enrichment potassium in Earth's crust was
universal, suddenly and global as a geochemical phenomenon. It has received in
the geological literature the name " of potassium explosion ". The petrological
consequence “of potassium explosion” was an extremely wide development of
granites and formation a granite layer in the Earth's crust. The cause of this
appearance it is necessary to search in evolution of composition of the mantle.
The potassium is the strongest chemical base and carreing out of it is)
connected with the change of an acid-basic mode of interaction in the bowels of
the Earth. About it testifies the change of composition of fluids in the
geological time. The granulite metamorphism of early Archean proceeded
under influence of a waterless, sharply restored fluid, in which composition Н
2
and СН
4
prevailed.
For late Archean and Proterozoic formations more
typically was metamorphism of amphibolite facies, which mineral balance
demand high pressures of Н
2
О and СО
2
, otherwise completely oxidized fluid.
Thus, the occurrence of water in structure of a deep fluid and potassium
explosion are synchronous and, probably, are mutually caused. That was the
cause of wide display of acid granites and genetically connected to them
deposits of gold, uranium and others lithophile elements. The most ancient
granites have age near 3,7-3,5 Gа, however, it were mainly sodium granites –
enderbites, whose volume was rather small. Deposits of gold in connection with
enderbites are not fixed, that it is possible to explain by domination of waterless
granulite at that time.
Reprinted with permission from Publishing House Nedra.
Addition a resources of gold is made by M.A. Krutoyarskiy ( 2004 )
132
Table 3. Auriferous formations and their resources of gold on the Earth
Geochronology
3,0-
2,8
Ga
2,7-
2,6
Ga
2,5-
2,4
Ga
2,3-
1,7
Ga
1,6-
1,0
Ga
1,0-
0,54
Ga
540-
360
Ma
360-
250
Ma
250-
70
Ma
070-
20
Ma
020-
001
Ma
Type auriferous deposit:
I group. Pre-orogenic
volcano-sedimentary
ore formations:
37,000 t / 41.6 %
1. Аu-Fe-S volcano-
sulphide ore deposits:
5,000 t / 5.6 %
1,000
1,400
1,100
900
600
2. Аu-Fe-S carbonic-
sedimentary ore deposits:
17,000 t / 19.1 %
1,200
900
1,300
3,400
2,000
2,700
4,600
900
3. Аu-Fe-S volcano-
sedimentary ore deposits:
15,000 t / 16.9 %
2,000
8,500
900
2,200
1,000
400
II group. Post-orogenic
plutono-volcano
ore formations:
52.000 t / 58,4 %
4. Au – Cu porphyry ore
deposits
5,000 t / 22.5 %
2,000
2,800
5,000
5,000
5,200
5. Аu-Qu replacement
carbonate ore deposits:
5,000 t / 5.6 %
2,530
2,470
6. Аu-S polymetallic vein
in granite ntrusions:
14,000 t / 15.7 %
400
3,600
5,000
4,500
500
7.
Аu-Ag epithermal-
hydrothermal deposits:
9,000 t / 10.1 %
900
1,500
2,900
1,800
1,900
8. Аu-Sb-Hg epithermal-
hydrothermal
deposits:
2,000 t / 2.3 %
250
750
500
350
250
9. Аu-Cu-U deposits
Olympic Dam type:
2,000 t / 2.3%
2,000
10. Old metamorphic Au
placers:
80,900 t / 41.5 %
80,00
0
900
11. Mesozoic-Cenozoic
detrital Au placers:
23,000 t / 11.8 %
2,000
4,000
7,000
10,000
12. Entombment Au-U
weathering crust discordant
type : 2,000 t / 1.0 %
2,000
Total Au: 195,000 t
2,000
90,700
1,800
1,300
5,800
3,400
4,650
16,950 26,630 23,320 18,450
Total Au: 100.0 %
1.0 46.5
0.9
0.7
3.0
1.7
2.3
8.7 13.7 12.0 9.5
133
The change of geodynamic regime at development of the Earth in late
Archean was most likely caused by the beginning of its expansion. We explain
the process of oceanic formation by the general expansion of the Earth and,
consequently, on the area of the distribution oceanic crust. Relative distributions
of the areas of continental and oceanic crust show, that in order to account for
the oceanic formation it is possible to assume the increaseing of the Earth’s
surface approximately in 2.5 times (Larin, 1980). The geosynclinal structures
began to start on continents in Archean-Proterozoic time. The volcano-
sediment formations were deposited on the oceanic type crust in the troughs, as
the result of this process the green-stone belts were formed.
The formation of the ocean is a relatively young phenomenon. It is reliably
dated to start in the late Paleozoic and continued with maximal activity in Mesozoic
and Cenozoic aras. Most probably, the Pacific ocean is an exception, because its
peripheral structural features do not preclude initial growth in early Precambrian time
(Khain, 1971; Pushcharovsky,1972). The Earth’s expansion, as estimated by the
rate of the growth of the oceans, evidently, accelerated in current of time. The total
area of the “young” oceans ( the Atlantic, Indian, and Arctic), approximately equals
to the “old” Pacific ocean. The area of the bottom of all oceans has particularly
increased sharply at Mesozoic – Cenozoic eras, that is complied with the increasing
volume of water in oceans and indirectly with formation of a rich deposits of gold,
uranium and rare lithophile metals in the geosynclines and areas of tectono-
magmatic activization.
The lamination of external geosphere of the Earth on the crust, pirolite and
gipolite with rather contrast distribution of potassium, rubidium and,
accordingly, radiogenic strontium postulated in the past time the contrast
between the geochemical character of allocation of these elements in the zone
of sedimentation, depending on the process of the ocean formation, which
subsequently resulted in disclosure of more and more deeper horizons of the
planet. The carbonates of calcium fix the isotope composition of strontium in the
water, from which they fall out, that allows to consider the evolution of the ratio
87
Sr /
86
Sr in the ocean’s water of the Earth. The curve, describing the evolution
of isotope composition of strontium in the oceans at that time appeared rather
peculiar (Figyre 3),(Faure and Powell, 1972). Three cardinal perturbations are
clearly prominent on it, which, obviously, reflects essential changes of the image
of the Earth. The data show exponential increase of the relation
87
Sr/
86
Sr in
waters, circumfluent of the planet during the period from 3,0 up to 1,1 Ga. The
extrapolation of this curve until now has resulted to the modern value of the
isotopic relation of strontium in the continental crust. However, in late
Precambrian, approximately on the boundary of middle and upper Riphean, this
relation sharply deviates from the exponential dependence (perturbation А) that
testifies to the appearance of a source with the low isotope attitude of strontium
exposed on the extensive territory. According to V.N.Larin (1980), it is, most
probably, connected with the beginning of active the ocean formation, during
which low potassium emanated the tholeiite basalts in huge amounts, that
134
accompanied the formation of the oceanic depressions. It is possible to
Reprinted with permission from Publishing House Nedra.
Taken from Larin (1980). Modified by Krutoyarskiy ( 2004 ).
connect the sharp failure of the curve (perturbation В), coming on the end of
Paleozoic and beginning of Mesozoic, with the acceleration of the processes of ocean
formation in Mesozoic era, when there was disclosure the Atlantic and Indian young
oceanic depressions alongside with proceeding expansion of the existent Pacific
ocean.
The acceleration of the ocean formation, connected with the expansion of
the Earth, by all means should cause the strain, and at the end the break of the
mantle layer restite in the middle part of the ocean couch. It accompanied by the
rise and output on the surface the again formed silicate mattress of the layer B,
arising by the way of metasomatism of the intermetalic layer C of the upper
mantle. The content of Rb in intermetalic connections of the layer C should
indicate initial concentration of this element on the planet and, hence, should not
be less, than in gipolite. In this connection, the sharp increase of the relation
87
Sr /
86
Sr in oceanic carbonate sediments (perturbation С) is explained (Figure 3). At
the pressure of level 10 GPа and above, the formed silicate mattress should be
represented by spinel-garnet mineral association, whereas at reduction of pressure
will prevail ever more pyroxene-olivine paragenesis. As far as the isomorphic
capacity of lattices olivine and pyroxene is much lower, than at garnet and spinel
(in the attitude of potassium, uranium and others lithophile elements), the
change of mineral paragenesis, formed by metasomatic way in the bowels of
middle oceanic ridges, (necessarily) should necessarily be accompanied by an
increasing the gab of these elements. Exactly here it possible that a huge source
which was caused by late Jurassic the perturbation C in geochemistry of
135
potassium and strontium in the zone of sedimentation at the bottom of oceans of
the Earth (Larin, 1980).
The deep-water red clays of pelagian parts of the oceans along with the high
contents of ore elements have a sharply increased concentration of potassium and
uranium. In the light of what has been stated above, it should be connected, as far
as the ore matter, to axial parts of oceans, with process of silication intermetalic
joints of the upper mantle. Admit the community of sources for these elements
and ore matter, and also the same cause of conditionality of characteristic
"failures" on the curve evolution of potassion and radiogenic strontium in
Mesozoic-Cenozoic, it is possible to involve the data of isotopic strontium for
defining the time of the beginning of entrance ore matter through the axial zone of
oceanic couch. According to the curve, reflecting variation of the relation
strontium at ocean’s carbonates during the Phanerozoic, the first portions of ore
matter could begin to enter from the end of late Jurassis time (150-140 Ma), but
from the beginning of Cenozoic the process of endure of ore matter has become
more intensive. At that same time on the continents and transitive zones to the
oceans took place the processes of tectono-magmatic activity which generated a
lot of gold deposits (Table 2, Figure 4).
The formation of large and superlarge deposits of gold with reserves more
than 500-1000 t is connected with the periods of tectono-magmatic activity, at the
processes of reuvination and secondary concentration of gold by fluid and
hydrothermal solutions, rising from more young intrusions of granites and other
magmatic masses, lieing on significant depths from 1-5 up to 10 km (Boyle,
1955; Bache, 1987; Rundquist, 1993; Konstantin et.al, 2000; Safonov, 2003;
Potters et al., 2004).
REFERENCES
Bache J.-J. (1987). - World gold deposits, a geological classification. -
Elsevier Science Publishing Co., NY, p. 178.
Boyle R.W. (1955). - The geochemistry and origin of the gold bearing
quartz veins and lenses of the Yellowknife Greenstone belt. - Econ. Geol., N
50, pp.51-66.
Betekhtin A.G. (1950). - Mineralogy. – State Publishing House, M., p.956.
Emmons W.H. (1937). - Gold Deposits of the World. - NY.
Engel A.E.J., Itson S.P. et. al. (1974). - Crustal evolution and global
tectonics: a petrogenic view. - Geol. Soc. of America Bull., v.85, N 6, pp. 843-
858.
136
Gold. (2000). - Mineral Summary. - NDMP, Brazil, v.20, p.54.
Gold. (2004) - Minerals Yearbook, Metals and Minerals. USGS.
Washington,.pp. 32.1-32.13.
Goldsmidt V.M. (1937). – Crystalochemistry. –Khimtheorizdat, M .
Goncharov V.I., Vashilov Yu.Ya., Sidorov A.A.,, Volkov A.V., Gorjachev
N.A. (2004) - The Deep structure of large precious metal deposits of northeast
Asia. - ИГЕМ the Russian Academy of Science, M., pp.69-94.
Hutchinson R.W. (1975). - Lode gold deposits; the case for volcanogenic
derivation. - Portland, Oregon, Dep. Geol. Miner. Ind. Bull., , pp.64-105.
Konstantinov M.M., Nekrasov E.M., Sidorov A.A. et.al. (200). The
auriferous giants deposits of Russia and World. - Scientific world. M, p. 270.
Krutoyarskiy M.A., Larin V.N.Larin, Magakian I.G., Smyslov A.A.
(2000) – The Brief Explanatory Note to “ Metallogenic Map of the Geodynamic
Systems of the Pulsatory – Expanding Earth,” scale 1:15,000,000. - IANSS, S-
Pt.,Chicago, p.76.
Larin V.V. (1980). – The hypothes of primary hydridic the Earth. –
Nedra, M., p.215.
Petrovskaya N.V. (1955). - . To the question on principles of mineralogical
classification of types initial auric ores. – Trudy NIGRI, gold, vyp..20.
Peterman Z.E., Hedge C.E., Tourtelot H.A. (1970). - Isotopic
Composition of strontium in sea water throughout Phanerozoic Age. -_Geochim.
et Cosmochim. Acta, v.34, pp.105-120.
Pushcharovskiy Yu.M. (1972). - Introduction at tectonic of the Pacific
segment of the Earth. - Nauka, М.,, p. 222.
Ridler R.H. (1976). - Relationship of mineralization to volcanic
stratigraphy in the Kirkland lake - Larder lake area, Ontario.-Geol. Assoc. Can.
Proc., N 21, pp.33-42.
Rudnik V.A., Sobotovich E.V. (1984). - The Early history of the Earth. -
М., Nedra, p.349.
Rundquist D.V. (1993). – The epochs of reuvenation Precambrian crust
and their metallogenic meaning. - Geology of ore deposits. N 6, pp. 467-480.
Safonov Yu.G. (2003). – The auriferous deposits of the World - genesis and
metallogenic potential. - Geology of ore deposits, т.45, N 4, pp. 305-320.
For G., Pauell J. (1974) - Isotopes of strontium in geology. – Izdan. Mir,
M. p.214. orks the forecast was confirmed and the last “Gold Klondike” of the
XX century in Arctic was detected.
In 1996 Krutoyarskiy has written the
Shumilin M.V. (1996) - Balance of world production and resources of
Uranium. – Rasvedka i okhrana nedra., N3, pp.10-11.
137
About the Editor and Author
Mikhail A. Krutoyarskiy graduated from the
Leningrad State
University (USSR)
in 1953
as an
exploration geologist. Since 1954 to 1971 his industrial
and scientific activity was connected with Leningrad
Scientific
Research
Institute
of
Arctic
geology.
Krutoyarskiy has worked in geological mapping and
searching of diamondiferous kimberlites and placers on
the Siberian Platform. In 1956 he participated on
discovery of a new Olenek region and exploration the first
in Russia diamondiferous kimberlite pipe “Leningrad”.
Between 1959 & 1968, he has worked as a research
geologist for exploration of the Yakut province, studying
kimberlite rocks; mineralogy and physical properties of
natural diamonds. In 1961 Krutoyarskiy has created the
“Forecast map of searching a new diamondiferous
deposits on the North Siberian platform” (scale 1:500,000). From 1969 to 1971 he
mapped an ancient complex of metamorphic terrain on Anabar shield. As a result of these
explorations he had written a lot of scientific reports, articles and two books. In 1968 he
successfully defended his Ph.D. thesis on the diamondiferous of the Western Yakut
kimberlite province.
Since 1972 until 1992 Krutoyarskiy worked for the Scientific Research Institute
Okeangeologia as a senior scientific geologist, where he has led a new scientific direction -
the estimation of prospects the Arctic shelf for the diamonds and gold placers. To resolve
this problem he had made in 1972 the “Forecast map of auriferous North-Taimyr province”
(scale 1:1,000,000), where he segregated 9 perspective areas for searching gold deposits and
placers. Among them has been Cheliuskin peninsula, on which the Polar expedition has
found two gold placers in 1981. As a result of these was doctoral thesis of the “Metallogeny
of Geodynamic Systems of the Pulsating-Expanding Earth”, to which he has compiled the
“Metallogenic Map of the Earth”. The doctoral thesis and the map have been completed
already after his emigration in USA at the end of 1996. Now he is working as a consultant
geologist in U.S. Geological Survey and at the International Academy of Natural and Social
Sciences. The vast scientific interests of Krutoyarskiy have found reflection in the numerous
published works, devoted to various questions of the geology, petrology and mineralogy of
kimberlites, diamonds and gold; to the forecast metallogenic diamondiferous and auriferous
maps. He has authored or coauthored of 5 books and more than 100 professional reports,
articles, geological and metallogical maps.
The completion of the collective work " Metallogenic Map of the Geodynamic Systems
of the Pulsating-Expanding Earth”(scale 1:15.000.000) and the “Explanatory Note” to it has
allowed M.Krutoyarskiy (as responsible editor) to take part in the International Geological
Congresses in Brazil (2000), Italy (2004) and Norway (2008). Presentation of this
Metallogenic map and Explanatory note has caused the great interest a geologists of the
world. The Russian Academician N.A.Shilo had written in his review, that this work “will
be splendour of modern geology” and allows on a scientific basis to discover the deposits of
useful minerals, where “Sezam opened the vaults to his treasures”.
138
(Click on the Map to open the full Map version)
(Click on the Map to open the full Map version)
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