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Gusev A.I.

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The appinites are characterized of high concentrations of magnesium, strontium, barium, light REE, that its show mantle nature (Fowler, Henney et al., 2001). They has low contents of niobium, tantalium. The ratio of Sr/Nd of isotope data are showed its generation from mantle of EM source (Fowler, Henney, 1996; Muir et al., 1997).

The appinites founded on Altai-Sajan region South Siberia in much sites: Aiskiy, Terandjikskiy, Tarchatinskiy areals (Gornyi Altai), Zhernovskoi, Gornovskoy, Borsukskiy (Salair), Telbesskiy (Gornaj Shoriaj), Saksyrskiy, Hemchikskiy (Sajan), Askizskiy (Batenevskiy krjadg), Beloiussko-Tuimskiy (Kuzneckiy Alatau), Borok-Bibeevskiy (Tom-Kolyvanskaja zone). The appinites of its areals occurred in the edges of stocks (2 - 96 km²) that has composite composition from monzogabbro to leicogranites.

The appinites in Gornyi Altai founded at edges of massifes of Aiskiy, Terandjikskiy, Tarchatinskiy complexes, that its time of moulding are in lower of Trias. This is time of generation different types of magmas and ores, connected with post collision setting, initiating by function with Siberian superplum. The stable paragenesis of dikes different composition from dolerites to granites with lamprophyres and massifs with appinites are watched in all areals. The lamprophyres are varies on different types of rocks (spessartites, vogesites, minetts, kersantites), but minetts occur in all areals from mafic to felsic types, that its relate to alkaline-basaltic of mantle magmas.

The appinites of Gornyi Altai are characterized by ours in detail (Gusev, Gusev, Tabakaeva, 2008). The intrusive massifs of Belokurikhinskiy complex (P₂-T₁) common occurrence in limits of Anuisko-Chuiskaja, Talitskaja, Biisko-Katunskaja, Balkhaschsko-Sadrinskaja, Teletsko-Chulischmanskaja, Holzuno-Chuiskaja structural-formation zones of Mountains Altai. The 5 phases derive in composite of complex in homodromic sequence: gabbro, diorites, syenites, grano-syenites, grano-diorites, granites, leico-granites, leico-granites with fluorite. The granitoids of Belokurihinskii complex carry for the first time to schoschonite type granite (SH). The petrologic peculiarities forming of intrusive massifs of complex discern and its fluid regime and role of fluid regime in generating of different types ore deposits.

The monzogabbro, monzodiorites, sienites are classified by appinites in different areals of Gornyi Altai, that has hybrid genesis and characterize high contents of MgO, Ni, Cr, Sr, Ba, light REE, and low concentrations of Nb, Ta (table 1).

The major and minor element variations are displayed in a series of rocks of Harker diagrams (Fig. 1). There are two main groups of elements. The first group incorporate elements which decrease steadly with increasing SiO₂, including TiO₂, Fe₂O₃, MnO, MgO, CaO. The second group incorporate elements that are concave downwards such as Al₂O₃ and Na₂O (Fig. 1).

The nomenclature of appinites are moderate alkaline, using plutonic TAS diagram of Middlemoust from monzogabbro to monzodiorite and monzonite. Some rocks fall within in fields of foid monzodiorite and foid monzosyenite (Fig. 2).

The compositions of appinites on diagram of Borodin´s (Ac -A0) are forming trend in field of moderete alkaline series (Fig. 3).

The ratio of (La/Yb)N decrease from monzogabbro (10,7) to melanosyenite (2,9), that it show on poorly fractionated rare earth patterns. Positive anomalous of Eu detects in all rocks. The magnitude of Eu*N decrease from monzogabbro (32,1) to melanosyenite (24,7).

The low silica contents and high MgO, Cr, Ni associated with high transition metal abundences in the monzogabbro and monzodiorites are consistent miwth mantle derivation and high Cr/Ni suggests significant high-pressure fractionation involving olivine.

Two isotope systems were studied to provide further constraints on the extent of crustal interaction during magma evolution. The ratio ⁸⁷Sr/⁸⁶Sr varies from 0,7051 to 0,7076 and ¹⁴³Nd/¹⁴⁴Nd from 0,51186 to 0, 51202. The ratio εSr(t) - εNd(t) form line trend composites from monzogabbro to melanosyenites and are located near enriched mantle source type EM II (Fig. 4).

Table 1. Chemical analysis of appinites of Gornyi Altai

Notes: samples were analyzed: for main components - chemical methods in Laboratory of IGaG SB RАS (Novosibirsk), for elements - method ICP-MS in Laboratory of IMGRE (Мoscow). Aiskiy areal: 1-3 - monzogabbro, 4-5 - monzonites, 6- melanosyenite; Terandjikskiy areal: 7- monzogabbro, 8 - monzonite, 9- monzodiorite; dikes: 10 -shonkinite; Tarchatinskiy areal: 11- monzonite.

The different types deposits connected paragenetic and spatially with areal development appinites of South Siberia. SW-Mo skarns, W-Mo greisen and lode deposits, pegmatite beryllium, Ta-Nb, Li deposits, so lode gold-sulfide-quartz manifestations connect with intrusive massifs with appinites in Gornyi Altai. The intrusive massifs of complex occur so in Rudno-Altaiskaja structural-formation zone (Tigirekskii, Savvuschinskii) and in Salair (intrusives early extracting Zhernovskoi complex), where there are deposits rare-earth elements in pegmatites, lode manifestations and anomalies Sn, TR, Ta, Nb.

The large deposits of Fe- skarns, Cu-Mo- porphyries are link with intrusive of Telbesskiy complex in Gornaj Shoria.

References

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2. Fowler M.B., Henney P.J. Mixed Caledonian appinites magmas: implications for lamprophyre fractionation and high Ba-Sr rranite genesis // Contrib. Mineral Petrol, 1996. - Vol. 126, -P.199-215.

3. Fowler M.B., Henney P.J., Darbyshire D.P.F., Greenwood P.B. Petrogenesis of high Ba-Sr granites: the Rogart pluton, Sutherland // Journ. Geol. Society, London, 2001. - Vol. 158. - P. 521-534.

4. Gusev A.I. The geochemistry and petrology of appinites association rocks of Gornyi Altai // The problems of geochemistry endogen processes and environment. - Irkutsk, 2007. - P. 123-125.

5. Gusev A.I., Gusev N.I., Tabakaeva E.M. The petrology and ore mineralization of Belokurikhinsiy complex of Gornyi Altai. - Biisk, 2008. - 193 p.

6. Middlemoust E.A.K. Naming materials in the magma/igneous rock system // Earth-Sci. Rev., 1994. - Vol. 37. - P. 215-224.

7. Muir R.J., Ireland T.R., Bentley M.R., Fitches W.R., Maltman A.J. A Caledonian age for the Kirolan Bay appinite intrusion on Colonsay, Inner Hebrides // Scottish Journ. Geol., 1997. - Vol. 33. - P.75-83.

8. Zindler A., Hart S.R. Chemical geodinamics // Ann. Rev. Earth Planet. Sci. 1986. V.14. P.493-571.

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