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dykes River Area Huor-Uyallah
Dykes in Namakan River Area. The composition of
clinopyroxene rock dyke polygons Namakan and
Huor-Uyallah the diagram Hess and features of the
distribution of Ca-chermakitogo components in
them I - glassy rock dykes Namakana,
II - crystalline rock dykes Namakana,
III - dykes Huor-Uyallah
The Low Triassic dyke swarm belt is strengthening at about 500 km along the northern margin of Siberian platform D ike area spread is limited to the
north rift structure of the Yenisei-Khatanga trough, and from the south - Kystyktah-Ayan-Ambardah uprise.
From west to east dyke belt is routed through Norilsk, Kamensky and Maimecha-Kotuiskaya province. In this regard, the composition of dykes
varies from basic rocks through basic and alkaline-alkaline to alkaline-ultramafic. Power dykes varies from 0,5-10m up to 90 m, length - from 5-15 m
to 140 km. The orientation of the bulk of dykes coincides with the direction of the major structural and tectonic elements of the region. dykes are often
confined to the fault plane and along the strike of the dykes of different composition are replaced by dykes. Within dyke hundreds of small intrusions
in the basalts are unevenly distributed. They form a compact package and swarms of dykes, stocks and subplastovye veins. An example is a portion of
the package dykes p. Huor-Uyallah where at a distance of 2 km there are 20 subparallel dykes of different chemical composition. Power ranges from
1.5-2m dykes up to 15m, the distance between the dykes from 4-5 to 150 m. Lack of convincing some cases the intersection of dykes others on this
and other sites gives reason to assume the formation of the dykes within a tectonic and magmatic cycle. dykes cross cut the entire incision plateau
basalts volcanic strata. They are not for pokrovoobrazuyuschimi effusions and are at the final stage of the platform trap magmatism. Ar / Ar age of the
youngest dykes in the province Kamenska 238-247 million years old, the age of minette dyke (LAMPROITES) in the province of Norilsk 235 million
years.
dykes are presented dolerite trachydolerites, syenite, Minetti, bostonitami, different in composition lamprophyres (camptonite, spessartite, Vosges),
avgitite, melanephelinite, alnёite, limburgite alkaline picrites, meimechites. The content of major oxides in rocks of the dykes vary widely: SiO2 35,762,6 wt.%; TiO2 0,4-7,5 wt.%; Al2O3 4,4-17,5 wt.%; Fe2O3 4,6-20,6 wt.%; MnO 0,08-0,44 wt.%; MgO 0,8-31,5 wt.%; CaO 0,7-15,4 wt.%; Na2O
0,01-6,5 wt.%; K2O 0,8-5,3 wt.%; P2O5 0,1-1,2 wt.%. Most highly alkaline dykes of basic rocks Bolsheavamskaya volcanic basin, which is
dedicated to Kamenskaja province. Here, among the dykes stand undifferentiated and layered dykes, glassy and crystalline, single and multi-phase,
with symmetric and asymmetric internal structure, with family and / or contrasting composition of the rocks of the individual phases. Multiphase dykes
in the area of the river. Namakan have a structure "in the dyke dyke" and symmetrical internal structure. Vitreous dykes are usually composed of
olivine clinopyroxenites, sometimes they are in the center of picritic porphyry. The number of phases in the implementation of dykes reaches five.
Symmetric with respect to the axis of the body structure creates similar in structure and composition of the left and right semi- dyke. Each phase of the
implementation structure "in the dyke dyke" consists of the quench zone endocontact globules silicate glass and carbonate and the inner zone enriched
Ozell K-feldspar, potassium feldspar with Kaersutite and / or mica. In crystalline dykes The contact zones are composed variolitic clinopyroxenites,
central - Picritic porphyries. Clinopyroxene is present in the composition of various rocks. Endocontact zone composed of many dykes
clinopyroxenites that have arisen as a result of heteromorphic crystallization at a supercooled melt. A feature of the composition of clinopyroxene are
elevated content CaTi- and CaAl-tschermak components that support the alleged heteromorphic melt crystallization.
SiO2
1
2
3
4
5
6
7
8
9
10
Ar-Ar age spectra
86
Бостонит
0,715
240
1,7
38
1,3
36
0,9
34
Возраст, млн лет
80
Трахидолерит ЛП
0
20
40
60
80
37
Выделенный Ar, %
100
0,711
Вогезит
240
160
80
240
0
160
20
40
60
80
Выделенный 37Ar, %
0
20
40
60
37
Выделенный Ar, %
100
80
Трахидолерит ЛБ-1
160
0
20
40
60
Выделенный 37Ar, %
80
Возраст, млн лет
Монцонит 502
80
0,707
100
240
160
80
0
0,703
230
240 Возраст, млн лет
20
40
60
80
37
Выделенный Ar, %
65
3000
55
45
35
0,703
0,705
0,707
0,709
86
( Sr/ Sr)I
2000
1000
35
0,7011
45
55
65
45
55
65
87
3000
2000
1000
0,703
0,705
1,0
0,8
0,6
0,2
0,709 0,7011
( Sr/ Sr)I
0,707
87
35
86
Fig. 7. Photomicrographs of some types of dyke rocks.
Fig. 8. Diagram
(Na2O + K2O) SiO2 dykes north of
the Siberian
platform (uploaded
circles). Gray box the composition of
rocks layered
intrusion Dyumtali
in Taimyr.
K2O
1,9
4
1,5
3
1,1
2
Ar-Ar ages of the dykes
Sills and
Early
Dykes flows
sills
0,7
Al2O3
P2O5
8
0,6
6
0,4
25
0,2
4
Fe2O3
Ba
16
0,16
0,12
14
0,08
0,04
12
20
П.п.п.
MnO
0,5
11
9
0,3
7
15
5
3
0,1
Sобщ.
MgO
25
0,2
20
10
0,1
15
0,0
10
CaO
CO2
8
16
5
4
12
0
8
| I | II | III | IV | V | IV | III | II | I |
| I | II | III | IV | V | IV | III | II | I |
Рис.4. Вариационная диаграмма оксидов (содержание в мас.%) в породах по разрезу
дайки Н-27/34. Штрих-пунктиром показан второй вариант строения IV-V фаз
в другом сечении дайки. Цифрами обозначены фазы внедрения расплава.
Fig.13. Depending on the content of the chart some of the mineral-oxide (wt.%) In
clinopyroxene glassy (box I) and crystalline (field II) dykes landfill Namakan.
1-4 - center (1), the edge (2) phenocrysts, microlite (3), dendrite (4) of the dyke H-27/34;
5-7 –Center (5), the edge (6) phenocrysts, microlite (7) of the dyke N-125;
8-10 - center (8), the edge (9) phenocrysts, microlite (10)
from the dykes H-121, H-126, H-127, H-132, H-13.
Melts in equilibrium with the phenocxrysts
Of the dykes
Fig. 11. The chemical
composition of subparallel
dykes River Huor-Uyalllah.
Oxide content in wt.%.
Bathed in circles - the central
part of the dyke, unfilled edge parts of the same body.
Fig. 12. Variation diagram
oxides (content in wt.%) In the
context of the multiphase
dykes H-27/34. Broken lines
shows the composition of
rocks IV-V phase in the other
section of the dyke. Roman
numerals - the implementation
phase of the melt.
100
260
250
0,5
TiO2
100
80
240
Na2O
40
ИКК-63
Минетта ЗП
160
Sr, ppm
Fig. 4. Dyke alkali augite picritesN-27/34. Namakan River dyke
landfill
87
( Sr/ Sr)0
Возраст, млн лет
magnesium lavas at the Northwest of the Siberian
Platform (Ryabov VV, Shevko AYa, Gora MP. Trap
Magmatism and Ore Formations in the Siberian
Noril'sk Region / Modern Approaches in Solid Earth
Sciences 3. Vol.1. Trap Petrology. Springer. 2014. 390 Р. 1
– dykes of mafic (a) and alkali-mafic – ultramafic (b)
rocks; 2 - paleovolcanoes; 3 – areas of maximum density
of picritic basalts of the Gudchikhinsky Suite. Various
hatching shows distributive areas and ages of highmagnesium lavas. Inset: the main abyssal faults are
shown: 1 – Noril’sk-Kharaelakhsky; 2 - LetninskImangdinsky; 3 - Pyasinsky; 4 - Kystyktakhsky; 5 Changaginsky; 6 - Romanikhinsky; 7 - BajkalTaimyrsky; 8 - Enisej-Giulinsky; 9 - Rassokhinsky; 10 Boganidsky; 11 - Mikchandin-Boruryakhsky; 12 Kourejksky.
Fig. 6. Sketches of
the internal structure
of glassy and
crystalline
symmetrical dykes.
Variolitic structure,
porphyritic.
Phenocrysts: augite
(black plate and
branched dendrites),
plagioclase (unfilled
rectangles), olivine
(hexagons: black fresh crystals
unfilled - modified),
small circles - the
amygdala.
Возраст, млн лет
Fig. 2. Schematic map of distribution of high-
Fig. 10. Dykes alkaline core (red) and fundamental
Fig. 5. Dyke dolerite NU-9/11. Polygon river dyke Uohir.
(green) rocks in basalts Mokulaevskoy Formation
(purple box). Polygon river dyke Huor-Uyalllah. At a
distance of 2 km from the 21 dyke.
(FeO+Fe2O3)
(FeO+Fe2O3+MgO)
Fig.1B The location of the dyke zone A plot of the dyke zone north of the
Siberian platform in the Kamenskaya province. Bold lines- alkali-basic
and ultrabasic dykes, bold dashed-dotted line - foults, dot dash dotboundary of Siberian platform.
Institute of Geology and Mineralogy, SB RAS, Novosibirsk, Russian Federation
Fig. 3. Mica picrite Dyke N-59/72. Namakan River dyke landfill.
Возраст, млн лет
Kamenskaya province
alkali-basic rocks in the
Northwest of the Siberian
platform. Dotted line
border trap basalts fields of
the Siberian platform and
Taimyr orogen. Black
rectangle - Kamenskaya
alkali-basic province
Post Siberian P-T superplume dyke belt
in northern margin of Siberian platform
Victor Ryabov
Sr, ppm
Fig.1A. The location of the
dyke zone Kamenskaya
province alkali-basic rocks in
the Northwest of the Siberian
platform
0
230
240
250
260
Fig. 9. Composition diagrams (wt%) of high-magnesium magmatic rocks of the Northwest of the Siberian Platform (Ryabov
VV, Shevko A.Ya, Gora M.P. Trap Magmatism and Ore Formations in the Siberian Noril'sk Region / Modern Approaches in
Solid Earth Sciences 3. Vol.1. Trap Petrology. Springer. 2014. 390 R.
On the diagrams, the dots for compositions of small intrusions (K) of the Kamensky and Ust'-Delkansky Complexes units are
plotted. Suites: ar - Arydzhangsky; an - Ayansky; dl - Delkansky; gd - Gudchikhinsky; hn - Khonnamakitsky; mm Maimechinsky; mr - Morongovsky; tk - Tuklonsky.