Reservoir characterization and exploitation potential in Orinoco heavy oil belt in Venezuela

The Orinoco heavy oil belt is on the southern slope of the Eastern Venezuela Basin, with an area of 55 000 km². The heavy oil reservoirs were buried 350-1 200 m deep. The unconsolidated sandstones in Oligocene and Miocene worked as the main reservoirs, with the average porosity and permeability of 33.4% and 4 760×10^-3 μm², respectively. Reservoir temperature is 40-55 ℃. Reservoir pressure coefficient is about 1. Super heavy oil API is 7.5 °-9 °. Situ viscosity is 1 000- 6 000 cP. Reservoir effective thickness is 6-120 m. The original proven geologic reserve is 11 220×10⁸ bbl, and the recoverable reserve is 2 600×10⁸ bbl. There are five heavy oil developing blocks with daily oil production of about 72 ×10⁴ bbl. A set of economic and feasible developing technology series has been formed. The recoverable reserve of the developing blocks is about 3% of the total recoverable reserves of heavy oil belt, showing great exploration potentials.