KÜRE BÖLGESİNDE (KUZEY TÜRKİYE) BULUNAN CEVHER MİNERALLERİ VE KROM SPİNELLERİ ÜZERİNE BÎR NOT

Küre bölgesi, Pontidler'in batı kısmında Karadeniz kıyısından 20 km mesafede yer almaktadır. Jeolojisi, masif sülfit yatakları ve paleomanyetizması özel yayınlarda incelenmiştir (Güner, baskıda). Bu not, Küre kayaçlarından alınmış olan cevher mineralleri ve krom spinelleri üzerine yapılmış olan çalışmaları bildirmektedir. İçlerinde kromiyumun başlıca bir bileşen olarak yer aldığı spineller, peridotit, serpantinit ve metasomatitler de bulunmaktadırlar. Jeolojik bakımdan, Küre bazaltoidleri ve bunların alterasyon ürünleri arasındaki bağlayıcı unsur olarak önemlidirler (Güner, baskıda). İnceleme çalışmaları süresince, krom spinellerinin mikroprob analizleri, yansıma ölçümleri ve Vickers sertliklerinin tespiti yapılmıştır. Yansıyabilirlikler ve Vickers sertlikleri, masif cevherlerin çeşitli sülfit mineralleri, dissemine sülfit cevherleri ve bazaltoidlerin oksit fazları için de yapılmıştır.

A NOTE ON CHROME SPINELS AND ORE MINERALS FROM THE KÜRE AREA, NORTHERN TURKEY

The Küre area is situated 20 km from the Black Sea coast in the western part of the Pontides. Its geology, the massive sulfide deposits, and the paleomagnetism are treated in special publications (Güner, in press). The present paper reports work done on chrome spinels and ore minerals from the Küre rocks. Spinels, in which chromium is a major component, occur in peridotite, serpentinite, and metasomatites. Geologically, they play an important part as a connecting link between the Küre basaltoids and their alteration products (Güner, in press). In the course of study, microprobe analyses, reflectivity measurements, and determinations of the Vickers hardnesses of the chrome spinels were made. Reflectivities and Vickers hardnesses were also determined for the different sulfide minerals of the massive ores and the oxide phases of the disseminated ores and basaltoids. The microprobe chemical analyses of chrome spinels were made by a Cambridge Scientific Instruments «Geoscan Mk II». For the measurements of reflectivity, the writer used a Leitz Microscope Photometer MPW mounted on an Ortholux-Pol polarizing microscope connected to a light-measuring device (type BN 5002 T) with a high-stability current supply (type NSHM). A solid filter of 546 nanometres wavelength, was also employed. The reflectivity standard was a SiC (R=20 %) crystal,, polished and calibrated by Carl Zeiss Company. The Vickers microindentation hardness was determined using a Leitz DURIMET Small-Hardness Tester. Loads of 25, 50, 100, and 200 grams at indenting periods of 15 to 20 seconds were employed. 

___

  • Fregerslev, S. and Carstens, H., 1976, Chromian spinels in impact melt rocks of Lake Mien, Sweden: Geol. Foren. Forhandl., 98, Stockholm.
  • Güner, M., in press, Geology and massive sulfide ores of the Küre area, northern Turkey.
  • , in press, A paleomagnetic study of some basaltoids and ores from the Pontic Ranges, northern Turkey.
  • Ketin, 1., 1962, Explanatory Text of the Geological Map of Turkey (Sinop): M.T.A. Publ.
  • Odsner, O., 1961, Atlas der wichligsten Mineralparagenesen im mikroskopischen Bild. Bergakademie Freiberg.
  • Stanton, R.L., 1972, Ore petrology: McGraw-Hill, New York.
  • Uytenbogaardt, W. and Burke, E. A. J., 1973, Tables for microscopic identification of ore minerals :Elsevier, Amsterdam