Tektonizma, Alterasyon ve Ultramafik Sistemlerin Rolü

Elazığ Alacakaya ilçesi ve civarında yer alan ultramafik kayaçlar içerisinde tektonik hatlar boyunca gelişmişolan lisfenit oluşumları tektonik ve jeokimyasal işlevlerin ürünüdür. Bu kayaçlar yaygın olarak serpantinleşmişultramafitler içinde yeralır. Serpantinleşmiş ultramafitler, serpantin mineralleri (lizardit, krizotil) ve buminerallere eşlik eden talk, diyopsit ve kromit minerallerinden ibarettir. Bu minerallerin varlığı, magmatikkökene, ortamdaki akışkan varlığına ve yüksek reaksiyon hızına işaret etmektedir. Lisfenitlerin XRD yöntemiylebelirlenen mineral parajenezlerinde başlıca kuvars+dolomit, dolomit+kalsit+kuvars, dolomit+kuvars+manyezitbelirlenmiştir. Kayaçlarda serpantin+manyezit, manyezit+talk ve son olarakta manyezit+kuvars oluşumusıcaklık koşullardaki değişimi (redüksiyon,permeabilite) ve tektonizmaya eşlik eden silis aktivitesini gösterir.Mineralojik incelemelerle belirlenen olivin ve lizardit/krizotil gibi mineralleri çevreleyen kalsit, klorit, hematitprogresif alterasyon koşullarını, Ca ve CO2'ca zengin akışkanların etkisiyle Mg-silikatlarda meydana gelendeğişimleri ve karbonat oluşumunu belirtir. Mikroskopik incelemeler, kimyasal ve izotop analiz verileri,ultramafitlerde gelişen lisfenitlerin oluşumunda;Tektonizma, orta veya düşük derece sıcaklık ve su-kayaçetkileşimi süreçleri, karbonat aktivitesi ve progresif alterasyonun ilerlemesine sebep olmuştur. Silisli lisfenitoluşumunda sıcaklığın kısmen yüksek olduğu mineraller arası reaksiyon, tektonizma kontrolünde silisleşmeye vekarbonatlaşmaya sebep olarak görülmektedir.

Tectonism, Alteration and Function of Ultramaphic Systems

Tectonic and geochemical functions resulted in listvenite formations thriving throughout tectonic lines inultramafic rocks in Alacakaya province of Elazig. These rocks are most commonly found in serpentinisedultramafites. Serpentine minerals thriving in talc, diopside and chromite accompanying these minerals indicate aperidotitic origin, the presence of fluid in the environment and a high reaction rate. In the mineral paragenesis oflistvenites and ophicalcites determined by XRD method, quartz+dolomite, dolomite+calcite+quartz,dolomite+quartz+magnesite are mainly determined. In the serpentinised ultramafic rocks, serpentine+magnesite,magnesite+talc and finally magnesite+quartz formations show the change in the thermodynamical conditions (reduction, permeability) and the activity of silica. Encircling such minerals as olivine and lizardite/chrysotiledetermined by mineralogical examinations, calcite, chlorite, iddingsite and hematite zones indicate progressingmetamorphism conditions, the changes occurring in Mg-silicates with the effect of fluids rich in Ca and CO2 andthe formation of carbonate. As a result of microscopic examinations, and chemical and isotopic analyses, it canbe seen that tectonism, carbonate activity thriving with the hydrothermal functions of medium or lowtemperature and the progressive metamorphism are effective in the formation of ophicalcites thriving in theultramafics; the alterations of silicification-carbonatisation type thriving with the alteration functions in whichthe temperature is relatively high are active in the formation of listvenite.

___

  • 1. Abbas, L. N., (2001). Phase equilibria in the ultramafites zone, j ournal of geology, 24, 387- 411. 2. Akbulut, M., Pişkin, Ö. Karayiğit, A. İ., (2006). The genesis of the carbonatised and silicified ultramafics known as listvenites: a case study from the Mihalıççık region (Eskişehir), NW Turkey.Geol. J.geology, 41, 557-580. 3. Allen, D. E., Seyfried, D. E., (2004). Serpentinisation and heat generation: Constraints from Lost City and Rainbow hydrothermal systems, Geochim. Cosmochim. Acta, 6, 1347- 134. 4. Andreani, M., Luquot, L., Gouze, P., Godard, M., Hoise, E., Gibert, B., (2009). Experimental study of carbon sequestration reactions controlled by the percolation of CO2-rich brine through peridotites, Environmental Science &Technology, 43, 1226- 1231. 5. Arif, M., Moon, C. J., (2003). Geochemistry of serpentinised peridotites from the Indus suture ophiolite in Swat, NW Pakistan, Geol. Bull. Univ. Peshawar, 36, 1-10. 6. Ash, C. H. and Arksey, R. L,. (1990). The listwanite-lode gold association in British Columbia. Geological Fieldwork 1989, B.C. Department of Energy and Mines, 1990-1,365- 364. 7. Bach, W., Garrıdo, C. J., Paulick, H., Harvey J, and Rosner M., (2004). Seawater-peridotite interactions: First insights from ODP Leg 209, MAR 15 N, Geochem. Geophys. Geosyst., 5, 9-26. 8. Baronnet, A., Boudier, F., (2001). Microstructural and microchemical aspects of serpentinisation. XI Annual V. M. Goldschmidt Conf erence, Art., p.3382. 9. Bashir, E., Naseem, S., Akhtar, T., Shireen, K., (2009). Characteristics of ultramafic rocks and associated magnesite deposits, Nal Area, Baluchistan, Pakistan. Journal of Geology and Mining Research, 1(2), 34-41. 10. Barret, D.C. and MacLean, F., (1994). Structural and calorimeter karbonatisation, Zeitschrif t f ür cristallography, 152, 211-233. 11. Beard, J. S., Hopkinson, L., (2000). .A fossil serpentinisation-related hydrothermal vent, Ocean Drilling Program Leg 173, Site 1068 (Iberia Abyssal Plain): some aspects of mineral and fluid chemistry. Journal of Geophysical Research, 105, 16527-16539. 12. Beinlich, A., Austrheim, H., Glodny, J., Erambert, M., Andersen, T. B., (2010). CO2 sequestration and extreme Mg depletion in serpentinised peridotite clasts from the Devonian Solund basin, SW-Norway, Geochimica et cosmochimica Acta, 74, 6935-6964. 13. Böhlke, J., K., (1989). Comparison of metasomatic reactions between a common CO2- rich vein fluid and diverse wall rocks; intensive variables mass transfers, and Au mineralisation at Alleghany, California, Economic Geology 84, 291-327. 14. Buisson, G., Leblanc, M., (1985). Gold-Bearing Listwaenites (Carbonatized Ultramafic Rocks) from ophiolite complexes; Centre Geologique et geophysique, universite des sciences et tecniques du languedoc, Montpellier, France. 15. Charlou, J. L., Donval, J. P., Fouque, Y., Jean- Baptiste, P., Holm N., (2002). Geochemistry of high H2 and CH4 vent fluids issuing from ultramafic rocks at the Rainbow hydrothermal field, Chem. Geol., 191, 345-359. 16. Cortesogno, l., Galbıati B, Principi G., (2001). Preorogenic metamorphic and tectonic evolution of the ophiolite mafic rocks (northern Apennine and Tuscany). Boll.Soc. Geol. Lt. 94, 291-327. 17. Dabitzias, S. G., (1981). Petrology and genesis of the Vavdos cryptocrystalline magnesite deposits, Chalkidiki Peninsula, northern Greece, Economic Geology, 75, 1138-1151. 18. Dick, H. J. B., Bullen, T., (1984). Chromian spinel as a petrogenetic indicator in abyssal and alpine-type peridotites and spatially associated lavas. Contrib. Mineral. Petrol., 86, 54-76. 19. Escayola, M. P., Proenza, J. A., Van Staal, C., Rogers, N., Skulski, T., (2009). The point Rosse listvenites, Baie Vert, Newfoundland: altered ultramafic rocks with potential for gold mineralisation?Newfoundland and Labrador Department of Natural Resources Geological Survey Report 09-1, 1-12. 20. Evans, B. W., (1977). Metamorphism of Alpine peridotite and serpentinite. Ann. Rev. Earth Planet Sci. 5, 397-447. 21. Faure, G., (1986). Principles of isotope geology. Wiley, Newyork 589pp. 22. Fruh-Green, G., Kelly, D. S., Bernasconı, S. M., Karson, J. A., Ludwıg, K. A., Butterfıeld, D. A.,Boschı, C., Proskurowskı, G., (2004). 30000 years of hydrothermal activity at the Lost City vent field. Science, 301, 495-498. 23. Frost, B. R. (1985). On the stability of sulphides, oxides and native metals in serpentinite, Journal of petrology, 26, 31-63. 24. Frost, B. R., Beard, J. S., (2007). On silica activity and serpentinisation, Journal of petrology, 48(7), 1351-1368. 25. Gerdemann, S. J., Dahlin, D. C., O’Connor, W. K., Penner, L. R., (2003). Carbon dioxide sequestration by aqueous mineral carbonation of magnesium silicate minerals. Second Annual Conference on Carbon Seqestration,Alexandria, VA, Mayy 5-8, 2003. Report No. DOE/ARC- 2003-018, OSTI ID: 898299(8). 26. Halls, C., Zhao, R., (1995). Listwanite and related rocks: perspectives on terminology and mineralogy with reference to an occurrence eat Creggan Baun, Co. Mayo, Republic of Ireland, Mineral. Deposita, 30, 303-313. 27. Hoefs, J., (1987). Stable ısotope geochemistry, third ed. Springer, Berlin, p. 241. 28. Jarosch, D., (1985). Bestatigung der Aplanaritat der Karbonatgruppe in AnkeritemitRöntgenVierkreisdiffraktometer- Daten. Anzeiger der osterreichischen akademie der wissenschaften, mathematisch- naturwissenschaf t e. Klase, 121, 61-62. 29. Kelley, D. S., Karson, J. A., Blackman, D. K., T. (2001). The AT-60 Shipboard party. An off-axis hydrothermal vent field near the Mid-Atlantic Ridge at 30N, Nature, 412,145-149. 30. Kelemen, P. B., Matter, J. M., (2008). In situ carbonation of peridotite for CO2 storage. PNAS 105, 17295-17300. 31. Kerridge, K. P., (1985). Crystal structures and cation sites of the rock-forming minerals, Acta Crstallographica, 26,923-946. 32. Maclean, F. S., (1990). High temperature crytal chemistry carbonate, American mineralogist, 63,71-111. 33. Mckelvy, M. J., Chizmeshya, AVG., Squires, K., Carpenter, R. W., Bearat, H., (2007). A Novel Approach to Mineral Carbonation: Enhancing Carbonation while Avoiding Mineral Pretreatment Process Cost: Tempe, Arizona State University, DOE Final Report 924162: AZ. 34. Milliken, K. L., and Morgan, J. K., (1996). Chemical evidence for near-seafloor precipitation of calcite in serpentinites (Site 897) and serpentinite breccias (Site 899), Iberia Abyssal Plain: in Whitmarsh, R.B., et al., Proceedings of the Ocean Drilling Program: Scientific Results, v.149, Ocean Drilling Program, College Station, Tex., p. 553-558. 35. Nasir, S., Al Sayigh, A. R., Al Harthy, A., (2007). Mineralogical and geochemical characterisation of listwanite from the Semail Ophiolite,Oman, Chemie der Erde-Geochemistry,67, 213-228. 36. Nixon, G. T., (1990). Geology and precious metal potential of mafic-ultramafic rocks in British Columbia: Current progress. Geological fieldwork 1989, paper 1990-1, a summary of field activities and current research, province of British Columbia, Mineral Resources Division Geology Survey Branch, 353-358. 37. Ohmoto, H. (1972). Systematics sülfür and carbon isotopes in hydrothermal ore deposits. Econ. Geo. 67, 551-578. 38. Reeder, R. J.. (1983). Crystal chemistry of the rhombohedral carbonates. Mineralogical Society of America Reviews in Mineralogy, 11, 1-47. 39. Robinson, P., Malpas, J., Zhou, M. F.. (2005). Geochemistry and origin of listwanites in the Sartohay and Luobusa Ophiolites, China, International Geology Review, 47, 177-202. 40. Rollinson, R.. (1993). Using Geochemical Data:Evaluation, Presentation, Interpretation, Longman Scientif ic&Technical: Essex. 41. Russell, M. J., and Hall, A. J., (1997). The emergence of life from iron monosulphide bubbles at a submarine hydrothermal redox and pH front. Journal of the Geological Society, London 154, 377-402. 42. Seravkin, I. B., (2007). The types of pyrite deposits in the South Urals and the sources of ore substance, in: Endogenic mineralisation in mobile belts, Proc. Intern. Sci. Conf . (in Russian). IGG UrO RAN, Yekaterinburg, 58-62. 43. Sleep, N. H., Meibom, A., Fridiksson, T., (2004). H2-rich fluids from serpentinisation: geochemical and biotic implications, Proceeding of the National Academy of Sciences, 104, 12818-12823. 44. Uçurum, A., (2000). Listwanites in Turkey: perspectives on formation and precious metal concentration with reference to occurrences in east-central Anatolia, Of ioliti, 25, 15-29. 45. Von Hanold, W., Weber, B., (1982). Schwarzer calcit von der Schwaebischen Alb, Auf schluss, 33, 45-48. 46. Xu, T. E. L., Sonnenthal, N., Spycher, N., Pruess, K., (2004). TOUGHREACT user guide: A simulation programme for non-isothermal multiphase reactive geochemical transport in variable saturated geological media. Lawrence Berkeley national laboratory report LBNL-55460, Berkeley, California, 192 pp.