Hydrocarbon Migration Istvan Csato University of South Carolina Department of Geological Sciences Petroleum Geology Class 745 Spring 2002
Hydrostatic condition: Buoyancy
Capillary Pressure Capillary pressure Condition of migration
Migration Critical height of oil stringer:
Migration
Darcy’s law: specific discharge [m/s] permeability of the matrix [m 2 ] viscosity of oil [kg/m/s] mean radius of the rock pores [m] tortuosity porosity oil saturation Migration
Vertical flow: q o =11.3 cm/year Updip flow at 2 o slope: q o =0.4 cm/year
Hydrodynamic Conditions
Hydrodynamic Traps
Compaction
Overpressure
Origin of Fluid Flow 1. Restricted-compaction 2. Meteoric Water Recharge
Mass conservation equation: Fluid flow equation (Darcy’s Law): Fluid Flow Compaction Fluid Flow - Compaction
Effective Stress - Porosity
Hydraulic fracturing
Primary and Secondary Migration as a function of rock permeability Primary Migration Secondary Migration
Migration and Accumulation
Migration from Shale to Sandstone
Migration through Fractures
Example
Origin of Fluid Flow 1. Restricted-compaction 2. Meteoric Water Recharge
Hydrodynamic Traps
Tilt of Oil-Water Contact