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Aşıköy.Toykondu masif sülfid yatakları Küreofiyolit birliğinin üst birimini oluşturan bazaltik sen içerisinde yer alır.Altta masif, üste doğru yastık lavları ve hiyaloklastitler şeklinde gözlenen buserinin jeokimyasal yönden okyanus sırtı bazaltları karakterinde olduğubilinmektedir. Bazaltlar, altta şeyl seviyelerinin hâkim olduğu, yukarıya doğruşeyl kumtaşı ardalanmaları 9995 gösteren kırıntılı sedimanter bir seritarafından örtülür. Cevher genellikle bazaltik serinin üst seviyelerinde, bazaltlarile şeyl ırasında belirli bir geometrik şekle sahip olmayan devamsız kütlelerhalinde gözlenir. lavantası konumunda olan şeylin hemen •altında yüksek tenörlüve masif yapıda olan cevher, alt seviyelere doğru kısmen ağsı, sonra saçınımlıyapıdaki cevhere geçiş gösterir. Yapısal yönden Aşıköy yatağıkuzeybatı-güneydoğu doğrultulu, güneydoğu dalımlı bir sırt görünümünde olup.genellikle eksone paralel faylarla dilimlenmiş durumdadır. Aşıköy ve Toykonduyatakları görünür kategorisinde % 1. 99 Cu ve % 35.13 S tenörlü toplam 10.4milyon ton cevher içerirler. Esas cevher mineralleri pirit ve kalkopirittir.Ekonomik açıdan önemli kobalt minerallerinden linneit, bravoit ile nabit altınarastlanmaktadır. Diğer sülfürlü ve oksitli birincil mineraller ile ikincilmineraller ekonomik yönden önemli görülmemektedir. Cevherleşmenin esas olarakLiyasdaki denizaltı volkanizması ve onu takibeden hidrotermal süreçler sonucu,dar ve kısa ömürlü, muhtemelen yay ardı kenar bir havzanın yayılma eksenicivarında oluştuğu, Doggeroeki plütonik sokulumlara bağlı olarakremobilizasyona uğradığı düşünülmektedir., Massive sulfide deposits of Küre occur in a basaltic sequence, the uppermost unit of the Kure ophiolite. This unit is massive at the bottom and passes into the pillow lavas and hyaloclastites towards the top. Geochemical analyses indicate an origin of oceanic ridge basalt. The basalts are overlain by a detritic sedimentary sequence represented essentially by shales at the base and shale-sandstone alternations at the upper levels Beneath the shale, the ore is generally massive and has a high grade, and towards the tower levels of the basalts it becomes stockworked and disseminated Structurally, the Aşıköy ore deposit has a form of ridge with a general direction of N45 W The average grade of the ore is 1 96 % Cu and 35 % S. Main ore minerals are chalcopyrite and pyrite. Cobalt minerals like linneite, bravoite and native gold minerals are also present. Ore mineralization is mainly thought to be the result of submarine volcanism and hydrothermal processes occurred during the Lias It probably developed near a spreading axis of a narrow and short-lived back-arc marginal basin and remobilized later due to granitic intrusions of Dogger age.

In this study, the geology of diabase dikes which cut peridotites of Yüksekova Complex (Özalp, Van, Turkey) and the effects of Ca metasomatism that caused the metamorphism of these peridotites were investigated. Within the light of mineralogical and petrographical studies and geochemical data; it was determined that diabase dykes that cut peridotites in Yüksekova Complex had shown rodingitization in various degrees due to Ca metasomatism. Depending on this metasomatism, Ca-Al-Mg rich silicates were formed. The mineralogy of rodingitized dikes with ophitic texture is composed of diopside, plagioclase, hydrogrossularite, chlorite, epidote and in minor amounts phlogopite, prehnite, apatite, calcite, opaque minerals. Metasomatism caused enrichment of Ca and depletion of SiO2in whole rock major oxides of dikes in tholeiitic character. So, dikes were divided into three different subgroups. The first group is formed from high grade rodingitized diabase dikes (~38.0–42.0 wt.% in SiO2; 19.0–26.0 wt. % in CaO). The grade of rodingitization in diabase dikes forming the second group is relatively low (~42.5–43.0 wt. % in SiO; 14.5–15.0 wt. % in CaO). However, the effect of rodingitization has not been encountered due to results of both petrographical and geochemical analyses in diabase dikes which form the third group (~47.0–50.0 wt. % in SiO; 10.0–12.0 wt. % in CaO). It is considered that in rodingitized dykes of which are enriched by trace and REE (Rare Earth Element) contents, the fluids affecting the metasomatic source have developed as a result of interactions with other rocks which were enriched more in these elements. It is also contemplated that the local geology, tectonical structure of the environment and the heat, oxygen fugacity and chemical composition in fluids which would develop due to those factors are significant in this interaction

The Eldivan Ophiolite is located at the central part of the İzmir-Ankara-Erzincan Ophiolitic Belt which is between Şabanözü, Eldivan and Korgun towns. From bottom to top, units forming the ophiolite consist of volcano sedimentary and metamorphic series, tectonites, cumulates and sheeted dikes. Tectonites, which are the main subject of the study, are generally represented by harzburgites and occasionally consist of dunite, pyroxenolite and chromitite levels. In harzburgites which have traces of plastic deformation (foliation, lineation and folding), the minerals display a distinct orientation as a result of intra crystallographic dislocation and grinding mechanism. The degree of deformation decreases upwards. Less amount of clinopyroxene is encountered at lower levels of harzburgites which are composed of olivine (60-90%) and orthopyroxene (10-35%). There is also observed a decrease in the amount of orthopyroxene and an increase in chromite ratio towards upper levels. The composition of olivines is usually forsteritic and orthopyroxene is enstatitic and displays a slight impoverishment in Mg content towards upper levels. However, there is observed a decrease in the amount of chrome but an increase in aluminium amount in the upward direction. This situation can be explained as a result of the primary composite of upper mantle and partial melting processes.