Turkey is characterized by the Alpine geosyncline and the orogenic movements. Most of the main metallic ore deposits are closely connected with the initial magmatism and late acidic magmatism in the eugeosynclines of the middle to late Alpine phases. The granitoids are seen in the Hercynian and Alpine cycles, which are evidenced generally by their radiometric ages. The intense plutonism is related with the middle and young Alpine orogenic phases in the Pontids and Anatolids tectonic belts. Kaman and Istranca granitoids, intruded into comparatively thick and large micro-continents of the Tethyan Sea, are characterized by high alkali contents and some of them are high in Al₂O₃ and low in SiO₂. On the contrary, those from the Eastern and Western Pontids are generally low in alkali, especially low in K₂O.
In general, the granitoids of relatively high-K₂O contents have connection with lead, fluorite and tungsten mineralizations, and in some areas show anomalous indication of tin. Molybdenum mineralization is rather intense in the Eastern Pontids where alkali ratio of the granitoids is similar to that of island arc granitoids. Although the Eastern Pontids have been correlated with the porphyry copper belt of Srednogorie in Bulgaria and of Minor Caucasus in USSR, subdivision of the copper and molybdenum belt may be possible along the Eastern Anatolids and Sevan-Akera ophiolite zones, on the basis of metallogenic characters.

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Around 2, 000 samples were taken from 48 drill holes perforated near Fukazawa Kuroko deposits to determine the alteration minerals by X-ray diffractmeter. The zonal arrangement of the alteration minerals was clarified in both the hangingwall and the footwall. In both walls, the amount of montmorillonite was revealed to decrease and that of sericite to increase towards the ore deposits, and zeolitic minerals (such as mordenite and analcime) to occur only in the parts far away from the ore deposits.
In hangingwall, montmorillonite-lack zone was found just above the ore deposits like as a ring. Montmorillonite in the inner part of the ring shows low d₀₀₁ values that suggest high Na content. On the other hand, montmorillonite in the outer part of the ring shows rather high d₀₀₁ values that do not mean high Na content. DATE, et all (1979) showed the existence of the dacite very poor in Na₂O just below the ore deposits. It is likely that, some amounts of Na₂O that was leached from the dacite and its pyroclastic rocks below the ore deposits seem to be settled in Na-montmorillonite just above the ore deposits after the formation of the ore deposits.

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Vitrinite reflectivity and illite-montmorillonite mixed layer minerals from borehole samples in the west of Sannohe district were studied in order to obtain information on thermal histry of the Miocene sediments in the Green Tuff region, northeast Honshu, Japan. The isoreflectivity-line profiles show an increase in reflectivity toward the west. The reflectivity gradient ranges from 0.05 to 0.08%R/100 m in the boreholes of the eastern part, and 0.3 to 1.4%R/100m in the 52MAHD-4 borehole of the western part. The unusually high gradient of the 52MAHD-4 borehole suggests anomalously high heat flow in the Miocene.
Highly expandable illite-montmorillonite mixed layer minerals (more than 80% expandable layers) begin to decrease rapidly the proportion of expandable layers at a vitrinite reflectivity of 0.7%. Based on BOSTICK's vitrinite reflectivity-temperature-time diagram, from the measured reflectivity on the "short burial" line of the diagram, the past temperature at the beginning of the conversion is estimated to be 100°C.

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In Ezuri mine, Mn-minerals such as braunite, serandite, Mn-dioxide and Mn-carbonate were found abundantly at the hematite-quartz zone just on or the same horizon as that of Ezuri black ore deposits. The part containing braunite, serandite and others cuts sharply the part of colloidal Mn-dioxide. Therefore, it seems that some raise of temperature and pressure caused recrystallization of braunite, serandite and others from Mn-dioxide.
Stilbite also was found only in the cracks of porphyritic dacite (lava flow or shallow intrusion) that lies above the ore deposits.

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[in Japanese]

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