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Carbonatite and alkaline
magmatism in central-east of Anatolia (Malatya,
Turkey)
Ilbeyli N.*,
Ozgenc I.**
* Akdeniz University,
Faculty of Engineering, Department of Geological Sciences, 07058
Antalya, Turkey;** Dokuz Eylul University, Faculty of Engineering,
Department of Geological Sciences, 35160 Izmir, Turkey
ilbeyli@akdeniz.edu.tr
Turkey is located within the
Eastern Mediterranean part of the Alpine-Himalayan orogenic system. It
consists of a number of continental blocks disconnected by ophiolitic
suture zones. These sutures mainly
formed from northern and southern branches of the Neo-Tethyan
ocean during the Late
Cretaceous-Eocene (Sengör and Yilmaz, 1981).
The study area is located in
the eastern part of central Anatolia. Although the investigated area is
situated in the eastern Tauride platform, some authors (Boztug, 2000)
argued that they are located in the central Anatolian crystalline
complex (Göncüoglu et al., 1991; Boztug et al., 2007).
The collision-related Late
Cretaceous alkali magmatic rocks occur around the Hasancelebi and
Basören regions (Malatya) (Ozgenc and Ilbeyli, 2009). Carbonatitic rocks
found within the syenites around Basören area (Ozgenc and Ilbeyli,
2009). REE, Mo and Th mineralizations are quite common in these syenites
and are associated with skarn formations.
The alkaline rocks around
Hasancelebi occur as stocks. They are mainly syenite, quartz syenite
and, rarely, monzonite and quartz monzonite. They are cut by aplitic,
pegmatitic and mafic dykes and enclaves are common. The rocks are
pinkish, medium-grained to porphyritic (Ozgenc and Ilbeyli, 2009).
Those around Basören are also
found as stocks. They are feldspathoid (nepheline, ± sodalite) syenite.
They are pinkish to grey, medium-grained to porphyritic. They are cut by
grey, dark grey-colored feldspathoid-bearing and mafic dykes. The former
is fine-grained, locally porphyritic, with leucite and mainly phonolitic
in composition (Ozgenc and Ilbeyli, 2009). Carbonatitic rocks are found
as dykes within the syenites in Basören area, where carbonatite-hosted
fluorite deposits are also common (Ozgenc and Kibici, 1994; Ozgenc,
1999).
This calcium-carbonatite is
the last-stage of the intrusion resulting the fenitization of the
syenites (Ozgenc, 1999).
The
plutonic rocks show a range in SiO2 values from 54 to 72
wt.%; the least acidic ones belong to the Basören rocks. All intrusive
rocks are mainly peralkaline and alkaline-oversaturated. The Basören
rocks are more strongly alkaline and less silica-saturated compare to
the Hasancelebi rocks. The alkaline rocks around Hasancelebi display
field, petrographic and geochemical characteristics similar to A-type
rocks.
All
intrusive rocks show enrichment in LILE and LREE relative to HFSE. Trace
element versus trace element ratio diagrams display that all rocks
derived from an enriched mantle source region(s). Whereas the Basören
rocks carry more intraplate component than the Hasancelebi rocks. These
diagrams also indicate that Hasancelebi and Basören rocks may not be
formed from the same parental magma (Ozgenc and Ilbeyli, 2009). These
alkaline-peralkaline magma(s) associated with carbonatite-rich rocks
could be derived from metasomatized lithospheric mantle. Therefore,
these carbonatite-rich rocks may also be
carbothermal residua rather than carbonatite.
References:
Boztug, D. S-I-A- type
intrusive associations: geodynamic significance of synchronism between
metamorphism and magmatism in central Anatolia, Turkey. In: Bozkurt E,
Winchester JA, Piper JDA (eds) Tectonics and magmatism in Turkey and the
surrounding area. Geol Soc Spec Publ No:173. 2000. P.407-424.
Boztug, D., Harlavan, Y.,
Arehart, G.B., Satir, M., Avci, N. K-Ar age, whole-rock and isotope
geochemistry of A-type granitoids in the Divrigi-Sivas region,
eastern-central Anatolia, Turkey. Lithos. 2007. Vol.97. P.193-218.
Göncüoglu, M.C., Toprak, V., Kuscu, I., Erler, A., Olgun, E. Geology of
the western part of the Central Anatolian Massif. Part I: Southern
Section. Turkish Petroleum Corporation (TPAO) Report. 1991. Report
No.2909. (unpublished, in Turkish).
Ozgenc, I. Carbonatite-hosted
fluorite and britholite mineralization at Sofular area, Malatya, Turkey.
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Proceedings of the Fifth Biennial SGA Meeting and the Tenth Quadrennial
IAGOD Symposium. 1999. P.663-666.
Ozgenc,
I., Kibici, Y. The geology and chemical-mineralogical properties of
britholite veins of Basören village (Kuluncak, Malatya). Geol Bull Turk.
1994. Vol.37. P.77-85 (in Turkish with English abstract)
Ozgenc,
I., Ilbeyli, N. Geochemical constraints on petrogenesis of Late
Cretaceous alkaline magmatism in east-central Anatolia
(Hasancelebi-Basören, Malatya), Turkey. Mineralogy and Petrology. 2009.
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Sengör, A.M.C., Yilmaz, Y. Tethyan evolution of Turkey: a plate tectonic
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