Meeting of Young Geoscientists Remnants of past percolation flow events entrapped in lateral secretion quartz lenses of the Ófalu Complex Tóth Ferenc Earth Science MSc II. SZTE, Department of Mineralogy, Geochemistry and Petrology Meeting of Young Geoscientists Tatabánya, 2012

The aim of the study ? ? Mórágy Complex paleohydrology research Advective fluid flow Diffusional fluid flow Vein-filling minerals - calcite and quartz Fluid Inclusion Plane (FIP) rock-bearing quartz ? Fluids from Ófalu Complex primary, vein-filling calcite fluid inclusions ? FIPs from Ófalu Complex, rock-bearing lateral secretion quartz (diffusive fluid flow events)

Geological overview of Mecsekalja-shear zone

Data comparison with Mórágy Complex fluids Applied methods 1. Texture Enclosing mineral Intracrystalline deformation Degree of recrystallization Data comparison with Mórágy Complex fluids Inclusion petrography 2. Cathodoluminescence microscope (CL) Intersection of recrystallized bands and FIPs 3. Microthermometry Fluid composition, formation conditions

Results I. Texture and deformation characteristics Intracrystalline alteration Defromation lamellae Low-degree recrystallization Moderate-degree recrystallization CL images

Results II. Fluid inclusion microthermometry Th: 134-270 °C Tm(Ice): -4,4- -7,9 °C Salinity: 7,21-11,73% wNaCl equiv. n= 49 Th: 75-123 °C Tm(Ice): -18,2- -24,6 °C Salinity: 20,05-25,83 wNaCl equiv. % n= 35 Th: 25,6-30,4 °C Tm(Ice): -56,2- -57,2°C

Deformation lamellaes Results explanation Quartz recrystallization conditions (based on texture) Progressive process! BLG II./SGR 360-410 °C BLG I. 300-350 °C Deformation lamellaes < 300 °C

Relative age of fluid inclusions Results explanation Relative age of fluid inclusions CL images Inclusion petrography I. group NaCl-H2O Wide interval of Th ″relict″ and ″neonate″ inclusions Entrapment: before recrystallization II. group NaCl-CaCl2-H2O Irregular shape ″diffusive″ spread in recrystallized zone Entrapment: after recrystallization III. group CO2-H2O Decarbonization Entrapment: before recrystallization

Results explanation Data comparison with previous fluids from the Mórágy Complex Poros et al. (2009) Ófalu Complex (FIPs) Mórágy Complex (FIPs) On the basis of Dabi et al. (2009, 2011) study Salinity is less or not sensitive compared toTh (Th is also sensitive to changes in fluid pressure) Not detected in vein-filling minerals in rocks of the Ófalu Complex

Results explanation Datas comperament with previous fluids from Mórágy Complex Szabó et al. (2003) Ófalu Complex (FIPs) Mórágy Complex (Vein) FIP from rock-bearing quartz of Mórágy Complex Secondary fluid inclusions from Mórágy Complex Conspicuous analogy with primary origin fluids in vein-bearing calcite and dolomite of the Mórágy Complex Final phase, high salinity fluids of hydrotermal activity (Szabó et al. 2003) Diffusive vs. Fracture channelized flow

Results explanation Possible scenarios FIPs from Ófalu Complex and primary fluid inclusions from Mórágy Complex (Szabó et al. 2003) FIPs from Ófalu Complex FIPs from Mórágy Complex (Poros et al. 2009) Secondary fluid inclusions from Mórágy Complex Poros et al. (2009)

Discussion Lateral secretion quartz formation Progressive metamorphic phase I. FIP group entrapment Irregular inclusions shape Wide Th inerval Local fluid movement III. (FIP) group entrapment Metamorphic process (decarbonization of carbonate rocks) CO2 increasing because of the ductile deformation Local fluid movement Ductile deformation 320-270 million years, 350-450 °C (Lelekes-Felvári et al., 2000; Shatagin et al., 2004; M. Tóth et al., 2005) Related defromation marks in the quartz texture Irregular inclusions shape II. FIP group entrapment Direction of spread in the quartz was affected by the subgrain boundaries Regional fluid movement

Discussion Ófalu Complex Baksa Complex (Fintor et al., 2009) Deep basin or sedimental infiltration origin Diffusional flow Advective flow Primary entrapment FIP Mórágy Complex Téseny Sandstone Formation (Fintor et al., 2009) Deep basin or sedimental infiltration origin Geothermal heating Diffusional flow Advective flow Secondary entrapment Primary entrapment FIP Deep basin origin Advective flow Hidrothermal heating Primary entrapment

Thank you for your attention! I would like to express my thanks to my consultant, Dabi Gergely that he has called my attention to ″everything″ and was always ready to help me. Thank you for your attention!