Volume 25, 3, 2006
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Volume 25, 3, 2006 |
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L.A.
Baskakova. The events and stages of
geologic development of the continental part of eastern Russia in the Cenozoic
3
G.A.
Fandyushkin. Metamorphism of coals in
Northeastern Russia
19
P.S. Minyuk. The
Matuyama-Brunhes chrone boundary, and its biostratigraphic characteristics in
the Pleistocene deposits in the north of the Russian Far East
29
N.A. Goryachev, N.V. Berdnikov.
Types of ore-bearing granites of the south-eastern part of Mesozoides of
northeastern Russia, and their fluid specialization
40
V.G. Khomich, N.G. Boriskina.
The geological position of precious-metal
deposits of intrusive-volcanogenic framing of the Precambrian Gonzhinsky
protrusion (Upper Priamurye)
53
V.S. Rimkevich, Yu.N. Malovitskiy, L.P. Dem’janova, Yu.A.
Vorob’jev, R.V. Belov.
Experimental studies of processes of complex reworking of non-bauxite-ores of
the Far Eastern region of Russia
66
Yu.A. Shabanova, B.L. Zalishchak, M.A. Ushkova, N.S
Karmanov.
Smoky quartz in pegmatites of the
Verkhneshibanovsky tin-tungsten deposit (Primorye)
75
V.V. Ivin, A.N. Rodionov, V.G. Khomich, L.F. Simanenko,
N.G. Boriskina. Geological structure and
endogenous mineralization types of the Nizhne-Taezhny ore cluster (Primorye)
81
G.A. Chelnokov, N.A. Chepkaya, A.A. Karabtsov, V.I.
Kiselev, N.A. Zykin, V.A. Goryachev.
Geochemistry of carbon mineral waters and
water-enclosing rocks of the Lastochka deposit
88
Reviews
G.L. Kirillova.
Evolution of clastic sedimentology
98
Obituary
Valery I. Sinyukov (1949–2006)
105
L.A. Baskakova
The events and stages of geologic development of the
continental part of eastern Russia in the Cenozoic
Based on bio-climatic, tectono-magmatic, and morphostructural properties, the
Cenozoic is divided into three stages: Early Paleogene (Danian-Early Eocene),
Paleogene-Neogene (Middle Eocene-Miocene), and Late Neogene-Quaternary. Each of
the stages is divided into two substages; the first two have distinct features
inherited from the preceding stage. The inheritance is most vivid in flora
composition.
The first stage is generally characterized by inheritance in many parameters
from the Late Cretaceous manifested in the areal constraints imposed on
sedimentation, wide distribution of weathering crusts, and significant
involvement of Late Cretaceous elements in flora composition. The boundary
between the first and the second stage is marked by tectono-magmatic activation
and a transregional hiatus in sedimentation.
The second stage is distinguished by 1) wide manifestation of intra- and
marginal-continental rifting with a complex phasic character and asynchronous
foundation and formation of such large structures as the West Sikhote-Alin and
Moma rift systems; 2) multistep expansion of accumulative areas of different
morphostructural belonging; 3) intensification of the regional specific
character (structural-tectonic, litho-facial, and magmatic); 4) intense basal
volcanism, and commercial coal formation in the Far East region.
The first substage of the second stage (Middle-Late Eocene) is noted for
climatic optimum and rich subtropical vegetation with Early Paleogene relics.
The second substage (Oligocene-Miocene) is distinguished by the directional
oscillatory character of climatic variations, a warm-moderate coniferous –
broad-leaved type of flora, and wide development of lacustrine facies in the
Oligocene, particularly in the south of the Far East.
The third stage. Its lower boundary is asynchronous in the Far East (Miocene-Pliocene)
and northeastern (Middle-Late Miocene) regions. From the beginning of the third
stage a “glacial” type of climatic variations with frequent alternation of cold
and relatively warm phases sets in. The destruction of Turgaiskaya flora occurs,
and the present-day landscape-biotic aspect of the region is formed. Rapid
evolution of small and large mammals is noted (north-eastern part). An extensive
sedimentary cover is formed in the Arctic margin of the continent. In the middle
of the Neopleistocene rifting extinguishes, and the processes of lithospheric
compression intensify. At the boundary of the Pleistocene and Holocene mammoth
extinction is noted.
G.A.
Fandyushkin
Metamorphism of coals in Northeastern Russia
Coals in Northeastern Russia were formed during five age intervals in the Late
Jurassic, second halves of the Early and Late Cretaceous, and in the Eocene and
Miocene. The coals in the region are represented by all of their kinds – brown,
black, and anthracitic. It is established that black coals are found in all coal
age intervals; brown coals are characteristic of only Cenozoic units; and
anthracites are present solely in Lower Cretaceous deposits. Two principal types
of metamorphism are recognized: regional (geothermal) and thermal (magmathermal).
The main kind of coal metamorphism in Northeastern Russia is regional
metamorphism. A major factor of an increase in the degree of coal metamorphism
is believed to be temperature; an important condition is also geologic time. The
main regional pattern is recognized: the older the coals, the higher the degree
of their metamorphism. The average regional degree of coal metamorphism in
Northeastern Russia changes gradually from rank G in Upper Jurassic coals to
groups 1B-2B in Miocene coals. Some regional principles have been established:
the metamorphic degree of coals of all stratigraphic levels of coal formation
increases gradually from north-west to south-east, and it also depends on the
restriction of coals to certain geostructures. It is also ascertained that
regional metamorphism of coals is manifested in three directions: in an increase
in the stratigraphic depth of coal seams occurrence, in the degree of an
increase in the thickness of coal-bearing units, and in the coal seams dip
attended by the growing depth of their present-day occurrence.
P.S. Minyuk
The Matuyama–Brunhes chrone boundary, and its biostratigraphic characteristics
in the Pleistocene deposits in the north of the Russian Far East
The results of paleomagnetic study of Eo-Pleistocene-Pleistocene deposits in the
north of the Far East are summarized. The analysis of the Matuyama and Brunhes
chrone boundary in numerous sections of the Pleistocene in Yakutia, Chukotka,
Kamchatka, and central parts of the Magadan region is given. In Central Yakutia
the Matuyama–Brunhes chrone boundary lies in the layer of ferruginous pebble;
and in Eastern Yakutia, in the Olerskaya suite and its age analogs. It is fixed
in the marine Enmakayskaya and continental Elkhkakvunskaya suites in Chukotka,
and in volcanogenic strata in Kamchatka. This boundary is established in the
sediments of the Belichanskiy horizon of the Lower Pleistocene in the upper
reaches of the Kolyma River. During the reversal in the north of the Far East
distinct phytogeographic zoning already existed.
N.A. Goryachev, N.V. Berdnikov
Types of ore-bearing granites of the south-eastern part of Mesozoides of
northeastern Russia, and their fluid specialization
Throughout northeastern Asia, granitoid rocks formed in collision-related active,
and transform continental margin environments are known [19, 26, 29]. In terms
of their mineralogical and geochemical characteristics, they are of S- and
I-type / ilmenite (collisional) and I-type / magnetite (subductional and of
transform margins) granitoids. Mineral deposits and occurrences of gold, tin,
tungsten, bismuth, niobium, zirconium, and yttrium are related to these
granitoids. Using cryometric and thermometric techniques, we examined the
individual melt and fluid inclusions in quartz of granite rocks which are
related to gold and tin deposits. Homogenization temperature (Th) values for
crystallized melt inclusions in quartz range from 805 to 780°C, and those for
high-concentration solid phase-fluid inclusions are 600°C and higher. Th for
primary fluid inclusions ranges from 530 to 225°C, and for secondary ones ranges
from 370 to 155°C.
Irrespective of granite nature, fluid inclusions in quartz of granites contain
potassium and sodium chlorides. Fluid inclusions in quartz of S-granites are
filled predominantly with sodium chlorides; and those of I-granites, with
potassium chlorides. Carbon dioxide with an admixture of water, nitrogen and
methane is typical only of S- and I-type / ilmenite series granites, whereas
potassium, magnesium and lithium chlorites are typical of subduction-related
I-type / magnetite series granites. Ilmenite granites of S- and I-types contain
a compositionally similar fluid phase in inclusions, although a nitrogen-methane
mixture in I-granites displays a tendency to a more reduced character of their
fluid. This testifies to a genetic connection of these granite types, which
formed at different depths of a collision-related plutono-metamorphic system.
Fluid inclusions in gold-bearing granites have carbon dioxide with water and
sodium chloride composition with CH4 and N2 admixtures.
The total salinity of secondary inclusions reaches 8 % of NaCl eq..
Fluid inclusions in tin-bearing granites have generally chloride (KCl higher
than NaCl) composition; lithium and magnesium chlorides are present. The
salinity of primary fluid inclusions is up to 8,5 % of NaCl eq., and
secondary fluid inclusions are more concentrated (up to 22 % NaCl eq.).
V.G. Khomich,
N.G. Boriskina
The geological position of precious-metal deposits of intrusive-volcanogenic
framing of the Precambrian Gonzhinsky protrusion (Upper Priamurye)
An analysis of data on the geology of precious-metal deposits in the
intrusive-volcanogenic framing of the Precambrian Gonzhinsky protrusion made it
possible to establish that the location of ore-bearing veined-metasomatic bodies
in each certain case depends on different combinations of structural,
lithological, and magmatic factors. At the same time, the positions of different
deposits exhibit clear evidence of their similarity: restriction to the marginal
parts of intrusive massifs on the conjugation of the latter with
volcano-tectonic depressions. The description of thr Borgulicanskoe, Pionerskoe,
Pokrovskoe and Burindinskoe deposits is given.
The trend of variability, evident in the composition of aureoles of rock
metasomatic alterations and mineral composition of ore-bearing zones (from the
Borgulikanskoe to the Burindinskoe deposit), is, probably, dictated by the depth
of the development of mineralization and the distance of its location from the
center of the regional ore-magmatic system.
V.S. Rimkevich, Yu.N. Malovitskiy, L.P.
Dem’janova, Yu.A. Vorob’jev, R.V. Belov
Experimental studies of processes of complex reworking of non-bauxite-ores of
the Far Eastern region of Russia
The geological structure, balance reserves and perspective resources of
non-bauxite ore deposits of the Far Eastern region of Russia are considered.
Geochemical conditions facilitating contrast distribution of aluminium, silicon,
and their compounds between the co-existing phases have been established as a
result of the study of processes of complex reworking of non-bauxite ores by
methods of fluoride metallurgy and electrolysis. The results helped develop the
process flowsheet of manufacturing alumina fit for aluminium electrolytic
reduction, and also complex reworking of non-bauxite ores with subsequent
production of amorphous silica, flint, and other useful components was performed.
The geochemical characteristics of fluoride extraction, liquation, and
electrolytic extraction of aluminium, silicon and their compounds make a
contribution in the solution of the problem of expansion of the raw material
base of alumina and aluminium industries of the Russian Federation.
Yu.A. Shabanova, B.L. Zalishchak,
M.A. Ushkova, N.S Karmanov
Smoky quartz in pegmatites of the Verkhne-Shibanovsky tin-tungsten deposit (Primorye)
The paper reviews problems of crystal-bearing pegmatite formation and its
present-day state. The geology of chamber pegmatite with morion and smoky quartz
is considered. The results of inclusion study for quartz crystals from the
Verkhne-Shibanovsky tin-tungsten deposit with the associated morion and smoky
quartz are cited. We have carried out a quartz crystallographic features study,
sorting of inclusions by type, determination of medium character and
physical-chemical parameters of quartz formation: a temperature range of
450–465°Ñ, pressure 355–360 bar, solution concentration 36.7 %. NaCl eq.
V.V. Ivin, A.N. Rodionov, V.G. Khomich, L.F. Simanenko, N.G.
Boriskina
Geological structure and endogenous mineralization types of the Nizhne-Taezhny
ore cluster (Primorye)
The Nizhne-Taezhny ore cluster of Northern Primorye is a complex object
containing tin-polymetal-silver, polymetal-silver, and silver mineralization
proper. Silver-porphyry mineralization is also possible to be found. The
features of zonal distribution of mineralization relative to intrusive massifs
have been recognized.
G.A. Chelnokov, N.A. Chepkaya, A.A. Karabtsov, V.I. Kiselev,
N.A. Zykin, V.A. Goryachev
Geochemistry of carbon mineral waters and water-enclosing rocks of the Lastochka
deposit
Original data are offered on the geochemistry of underground waters and
water-enclosing rocks of the Lastochka carbon mineral water deposit. These data
in conjunction with new isotope data (d18O,
d2H, d13Ñ(PDB)) made it possible to
solve the problem of the origin and evolution of underground waters and gasses
at the deposit. Fresh (mineralization 0.1-0.5g/l) and carbon mineral (mineralization
3.7-4.7 g/l) underground waters were studied at the deposit. For the first time
data were obtained (3H) allowing us to estimate the rate of water exchange in
the water-rock-gas system at this deposit.