Based on the theory of oil and gas accumulation

the heavy oil accumulation conditions and characteristics of the Orinoco heavy oil belt were analyzed

and the exploration direction was pointed out.The Orinoco heavy oil belt is situated in the foreland slope region of low relief.Tectonic activity is weak and several small normal faults are developed in this region.The Upper Cretaceous Guayuta Group neritic shale is the main source rock

which features in large thickness

high abundance of organic matter and large hydrocarbon generation potential.The main reservoirs are sandstones of delta facies in the Miocene Oficina Formation and Oligocene Merecure Formation.They are characterized by large sheet-like distribution

stable thickness in East-West direction but decreasing thickness southwards

shallow buried depth

low degree of cementation

high porosity and high permeability

thus their reservoir properties are supreme.There are multiple seals such as regional cap rocks and bitumen overlying the reservoir

mudstone layers between reservoirs

and the underlying pre-Cretaceous basement at the side of reservoirs.The main trap type is lithologic stratigraphic trap.Fault

unconformity and connected sandstones are the major hydrocarbon migration pathways.Oil became viscose due to biodegradation during the long distance migration in the late Miocene and large-scale accumulation in Pliocene-Pleistocene.The accumulation of heavy oil has the characteristics of excellent source-reservoir-seal combination

long migration distance and strong viscosifying action.The accumulation model of heavy oil is long distance migration and biodegradation

large scale centralized accumulation in shallow reservoirs.Resources potential is huge in the Orinoco heavy oil belt.The Oficina formation is the key exploration target.The western part of the Orinoco heavy oil belt is the major exploration domain.Stratigraphic traps are the key trap type.