09. Vrstevní tlaky a přetlaky fluid ve vztahu k hydrostatickému a geostatickému tlaku: srovnání jihokaspické, východoslovenské a vídeňské pánve J. Francu1, I. Guliev2, A. Feyzullayev2, & M. Abrams1 1 Energy & Geoscience Institute, University of Utah, Salt Lake City, UT 84108, USA 2 Institute of Geology, AAS, H. Javid pr., 29A, 370143 Baku, Azerbaijan Acknowledgements Energy & Geoscience Institute, University of Utah, Salt Lake City, UT 84108, USA Institute of Geology, AAS, Baku, Azerbaijan Czech Geological Survey, Brno, Czech Republic for support during the collaborative research OBJECTIVES 1. Examine the effect of - Burial / sedimentation rate - Temperature - Organic Maturation & HC Generation on overpressure build-up and preservation 2. Compare case histories in selected basins with specific pT conditions GIA Mechanisms of Overpressure Build-up during burial Fluid Pressure Generation 1. Effective Stress => Compaction Disequilibrium 2. Fluid Volume Expansion - Heating - Diagenesis (Clay Dehydration) - Hydrocarbon Geneartion & Cracking to Gas 3. Fluid Migration - Hydraulic Head / Osmosis / Buoyancy Load Overpressure Preservation 1. Permeability Barrier - Hydraulically Sealed West Carpathians and Pannonian Basins Vienna Basin East Slovak Basin Str-21 Kút-26 Teplota s hloubkou 0 40 80 120 160 200 Temperature (°C) 6000 4000 2000 0 Depth(m) East Slovak Basin Vienna BasinSouth Caspian Basin Compaction Model - East Slovak Basin Transcarpathian Basin (East Slovakia) Rock-Eval Data with Depth 0 0.2 0.4 0.6 0.8 S1 (mg/g) 4000 3000 2000 1000 0 Depth(m) 0 0.5 1 1.5 S2 (mg/g) 0 200 400 600 HI (mg/g TOC) 400 420 440 460 480 500 Tmax ( C) Neogene Paleogene Paleozoic Vrstevní tlaky fluid ve východoslovenské neogenní pánvi Fluid pressure in East Slovak Basin 4000 3000 2000 1000 0 SP R STR-21 65% EXP in I/S 5% EXP in I/S Hydro-statický tlak Litostatický tlak Vrstevní tlak fluid Zóny tvorby ropy a plynu - Vrstevní tlaky GIA Seal = Shale 80% Anhydrite 15% Halite 5 % Zóna tvorby plynu Zóna tvorby ropy Hydro- statický tlak Lito- statický tlak Vrstevní tlak fluid West Carpathians and Pannonian Basins Vienna Basin East Slovak Basin Str-21 Kút-26 Vienna Basin Neogene & Quaternary < 5.5 km Heat Flow 45 - 63 mW/m2 Kuty Depression Porosity Reduction with Time & Depth Highly overpressured Vienna Basin Northern Vienna Basin Rock-Eval Data with Depth 0 0.5 1 1.5 2 2.5 S1 (mg/g) 6000 5000 4000 3000 2000 1000 0 Depth(m) 0 2 4 6 S2 (mg/g) 0 100 200 300 HI (mg/g TOC) 400 420 440 460 480 Tmax ( C) IMMATURE EARLY MATURE OIL WINDOW Neogene Cretaceous Triassic Thermal Maturity Hydrogen Index Residual Source Potential Free HC Fluid pressure in Vienna Basin SP R Kuty-8 4000 3000 2000 1000 0 Pressure (MPa) South Caspian Basin Oil & Gas Fields 100000 300000 500000 4300000 4500000 0 50,000 100,000 m Khamamdag-deniz - Aran-deniz Anticline Burial & Compaction History South Caspian Basin GIA Temperature with Depth in the South Caspian Basin Aran-deniz Khamamdag-deniz Garasu Sangi-Mugan 100-110 °C at 6 km GIA Maturation with Depth & Oil and Gas Generation Zones 0 Depth(m) Vitrinite Reflectance Ro (%) South Caspian Basin GIA 0.6 Fluid pressure in South Caspian Basin Lithology - Stratigraphy GIA Khamamdag-deniz Aran-deniz Anticline Sandstones Shales South Caspian Basin Thermal Maturity - HC Generation - Overpressure CONCLUSIONS Effect of Temperature and Sedimentation Rate on Overpressure 1. Overpressure occurs at variable level or organic maturation - Hot Basin - within the oil and mainly gas gener. w. - Cold Basins - fairly above oil window 2. Hydraulical Seal is a prerequisit for overpressure preservation - simplified modeling with barrier lithology Shale (80-85 %) Anhdrite (15-10%) Salt (5%) 3. Sedimentation/Burial rate is the principal variable in the applied modeling