P-T PODMÍNKY NÁSUNOVÉ DEFORMACE A CHARAKTER GENEROVANÝCH FLUID V HÁDSKO-ŘÍČSKÝCH VÁPENCÍCH NA HÁDECH U BRNA

Vol.11,(2004)

Abstract
Variscan hydrothermal calcite±quartz veins have been investigated by microthermometric and isotopic methods (O, C, Sr). Veins are located in the Hády-Říčka Limestones within a black coloured shear-thrust zone in the Růenin quarry at the Hády Hill. Organic matter in rocks has been transformed and aqueous and organic fluids have been derived by deformation processes and elevated temperature. The coexistence of CH4±CO2 and H2O-NaCl fluids trapped in fluid inclusions enabled to calculate P-T trapping conditions and formation of hydrothermal phases. Revealed pressure and temperature represent local conditions within shear zone, T = 130° - 250°C, P = 180-1200 bar. They exceeding regional parameters as a result of friction within rocks during a deformation event.

Keywords:
Moravian karst; Palaeozoic; quartz-calcite veins; P-T conditions; hydrocarbons
References

Abart, R. – Ramseyer, K. (2002): Deformation induced quartz-fluid oxygen isotope exchange during low-grade metamorphism: an example from the Glarus thrust, E Switzerland. – Schweiz. Mineral. Petrogr. Mitt., 82, 291–302.

Borisenko, A.S. (1977) Study of salt composition of fluid inclusions in minerals using cryometric technique. – Geol. Geofiz. 8, 16–27.

Davis, D.W. – Lowenstein, T.K. – Spencer, R.J. (1990) Melting behavior of fluid inclusions in laboratory-grow halite crystals in the system NaCl-H2O, NaCl-KCl-H2O, NaCl-MgCl2-H2O and NaCl-CaCl2-H2O. – Geochim. Cosmochim. Acta, 54, 591–601.

Dvořák, J. – Pták, J. (1963): Geologický vývoj a tektonika devonu a spodního karbonu Moravského krasu. – Sbor. geol. Věd, Geol., 3, 49–77. Praha.

Franců, E. – Franců, J. – Kalvoda, J. (1999): Illite crystalinity and vitrinite reflectance in Paleozoic siliciclastics in the SE Bohemian Massif as evidence of thermal history. – Geol. Carpath., 50, 5, 365–372. Bratislava.

Gray, D.R. – Gregory, R.T. – Durney, D.W. (1991): Rock-buffered fluid-rock interaction in deformed quartz-rich turbidite sequences, Eastern Australia. – J. Geophys. Research, 96, 19681–19704.

Gray, E.B. – Anastasio, D.J. – Holl, J.E. (2001): Synorogenic crustal fluid infiltration in the Idaho-Montana Thrust Belt. – Geoph. Res. Lett., 28, 22, 4295–4298.

Holloway, J.R. (1977): Fugacity and activity of molecular species in supercritical fluids. – In: Fraser, D.G. (ed.): Thermodynamics in Geology, 161–182.

Kettner, R. (1942): Nové pojetí tektonické stavby Moravského krasu. – Věda přírodní, 21, 2, 33–40. Praha.

Kirschner, D.L. – Kennedy, L.A. (2001): Limited syntectonic fluid flow in carbonate-hosted thrust faults of the Front Ranges, Canadian Rockies, inferred from stable isotope data and structures. – J. Geophys. Res., 106, B5, 8827–8840.

Krader, T. – Franck, E.U. (1987): The ternary systems H2O-CH4-NaCl and H2O-CH4-CaCl2 to 800 K and 250 MPa. – Ber. Bunsenges. Phys. Chem., 91, 627–634.

Kumpera, O. – Martinec, P. (1995): The development of the Carboniferous accretionary wedge in the Moravian-Silesian Paleozoic basin. – J. Czech Geol. Soc., 40, 1–2:47–64. Prague.

Rajlich, P. (1990): Strain and tectonic styles related to Variscan transpression and transtension in the Moravo-Silesian Culmian basin, Bohemian Massif, Czechoslovakia. – Tectonophysics, 174, 351–357.

Ramsay, J.G. (1980): The crack-seal mechanism of rock deformation. – Nature, 284, 135–139.

Richards, I.J. – Connely, J.B. – Gregory, R.T. – Gray, D.R. (2002): The importance of diffusion, advection and host-rock lithology on vein formation: a stable isotope study from the Paleozoic Ouachita orogenic belt, Arkansas and Oklahoma. – Geol. Soc. Amer. Bull., 114, 11, 1343–1355.

Slobodník, M. – Muchez, Ph. – Král, J. – Keppens, E. (submitted): Variscan veins in the Moravian karst (Czech Republic): record of fluid circulation and Late Variscan tectonothermal events. – Sediment. Geology.

Střelcová, E. – Franců, J. – Poelchau, H.S. (1997): Model tepelné historie paleozoika Konicka na základě odraznosti vitrinitu. – Geol. výzk. Mor. Slez. v r.1996, 4, 83–85. Brno.

Tissot, B.P. – Welte, D.H. (1984): Petroleum formation and occurrence. – Heidelberg, New York, Springer Verlag, 699 pp.

Zukalová, V. – Chlupáč I. (1982): Stratigrafická klasifikace nemetamorfovaného devonu moravskoslezské oblasti. – Čas. Mineral. Geol., 27, 3, 225-241. Praha.

Metrics

293

Views

152

PDF (Czech) views