Türkiye Jeoloji Bülteni

Origin and Formation Processes of Iron, Copper-Molybdenum and Lead Mineralisations of Karacaali (Kırıkkale) Magmatic Complex

Abstract: Karacaali magmatic complex, located at 10 km northeast of Kırıkkale town center, within the Kırşehir İ31-altopographic quadrangle of Turkey of 1/25.000 scale, mainly contains iron, copper-molybdenum and lead mineralisations. Karacaali magmatic complex is mainly composed of granitoid, rhyolite/rhyodacite and basaltic rocks Iron mineralisation mainly related to basaltic rocks in Karacaali magmatic complex, copper-molybdenum and lead-zinc mineralisations in granitic rocks are developed related to vertical or nearly vertical quartz,carbonate and turmaline with quartz veins. The main ore minerals are magnetite, hematite, ilmenite, pyrite, chalcopyrite, molybdenite, galena and sphalerite. The iron grade is within the range of 15%-60% FeO and the copper, molybdenum, lead, zinc grades are < 1,4 %, < 0,4%, < 0,1% and < 0,2%.Alteration types related to mineralisation are; tourmalinization, actinolitization, epidotization, chloritization and K-feldspar alteration in granitic and basaltic rocks, and argillation, silicification, alunitization in rhyolite/rhyodacites.Depending on the contact relations together with the structural-textural characteristics and the wall rockalterations, it can be concluded that the iron, copper-molybdenum and lead-zinc enrichments observed inKaracaali magmatic complex are the products of a single magmatic process. It is suggested that these mineralisations are associated with the interaction, assortment, mixing and differentiation processes taking place betweena granitic magma and a basaltic magma.