SULFUR ISOTOPE STUDY OF KURŞUNLU (ORTAKENT-KOYULHİSAR-SİVAS) VEIN TYPE PB-ZN-CU DEPOSITS

Yıl 1990, Cilt: 111 Sayı: 111, 52 - 52, 01.04.1990

Ahmet Gökçe

Öz

- Kurşunlu Pb-Zn-Cu deposits are the typical examples of the vein type deposits which are widely seen all over the southern and
western parts of Eastern Black Sea region. They are deposited along the fault zone which cut the Upper Cretaceous, mostly andesitic, partly dacitic
volcanic and volcanosedimentary rocks. Galena, sphalerite, pyrite, chalcopyrite, calcocite and hematite are seen as ore minerals while quartz,
calcite and small amount of barite occur as gangue minerals. Isotopic composition (d3 4SCDT) of the galena, sphalerite, pyrite and chalcopyrite
mineral separates from these mineralizations, are as follows; -6.6 - -8.4
o/
oo
, -4.6 -- 7.6
o/
oo
, -4.3 - -6.0
o/
oo
and -3.7--6.3
o/
oo
. These
are the negative values range between -3.7 and -8.4
o/
oo
. A possible isotopic equilibrium seems to be developped between sphalerite and galena,
and it suggests an average formation temperature of 327°C according to the sulfur isotopes fractionation thermometer. According to these
isotopic composition; It is very difficult to identify the source of the sulfur in these ore veins as magmatic, marinal or biologic. But it may be
suggested that the sulfur in this composition have been produced as follows; A magmatic sulfur with an isotopic composition nearly zero
(d34S ) which dissolved from the surrounding volcanic and volcanosedimentary rocks by deep circulated suificial water was shared between
sulfates (which useheavier isotopes; such as barite) and sulfides (which use lighter isotopes) of the veins as parallel to the isotopic fractionation
trend.

Anahtar Kelimeler

-

Kaynakça

• Coleman, M.L., 1977, Sulphur İsotopes in petrology: Jl. Geol. Soc. Lond., 133, 593-608, Great Britain.
• Gökçe, A., 1989, Kurşunlu (Ortakent Koyulhisar-Sivas) Pb-Zn-Cu yataklarında sıvı kapanım ve jeotermometre incelemeleri: TJK Bült. (incelemede).
• — ve Özgüneylioğlu, A., 1988, Kurşunlu (Ortakent-Koyulhisar-Sivas) Pb-Zn-Cu yataklarının jeolojisi: CD Muh.Fak.Derg., Seri A- Yerbilimleri, 5/1, 23-36.
• Faure, G., 1986, Principles of isotope geology: John Wiley and Sons Inc., 589 p., Canada.
• Hoefs, J., 1987, Stable isotope geochemistry (Third Edit.): 241 p., New York, USA, Springer Verlag.
• Ohmoto, H., 1986, Stable isotope geochemistry of ore deposits: Valley et al., ed., Stable İsotopes in high temperature geological processes da-, 491-559, Mineralogical Society of America.
• — ve Rye, R.O., 1979, İsotopes of »sulpfur and carbon: Barnes, H.L. ed., Geochemistry of hydrothermal ore deposits da., 506-567, Wiley, 798, Nevv York.
• Özgüneylioğlu, A., 1988, Kurşunlu (Ortakkent-Koyulhisar-Sivas)Pb-Zn-Cu yataklarının jeolojisi: Cumhuriyet Univ. Fen BiL Enst., Yük.Lis. Tezi, 52, (yayımlanmamış).
• — ve Okabe, K., 1981, Sivas-Koyulhisar-Sisorta-Kurşunluköy ve civan Kurşun-Çinko-Bakır madeni ayrıntılı jeoloji ve sondaj çalışmaları raporu: MTA Rap., 3855 (yayımlanmamış).
• Rye, R.O. ve Ohmoto, H., 1974, Sulphur and carbon İsotopes and ore genesis: A revievv, Econ.Geol, 69, p. 826-842, Bull of the Economic Geologist, Lancaster, USA.
• Robinson, B.W. ve Kusakabe, M., 1965, Quantitative preperation of Sulphur dioxide for 34S / S32 analyses, from sulfides by combustion with cuprous oxide: Analytical Chemistry, 47, 1179-1181, Bull. of the American Chemical Soci. Nevv York, USA.
• Spiro, B.ve Puig, A., 1988, The source of Sulphur in polymetallic deposits in the Cretaceous magmatit are, Chilean Andes: Jour. of South American Earth Sciences, 1/3, 261-266, Great Britain.