ABSTRACT
From the present 9-13 trillions of oil barrels that constitute the world oil reserves, 30% corresponds to conventional oil (greater than 22.3◦API), 15% to heavy oil (between 22.3 and 10◦ API) and 55% corresponds to extra-heavy oil, bituminous sands and bitumen (Alboudwarej et al. 2006). Many thermal processes have being developed to increase the recovery factor in the heavy and extra-heavy reservoirs around the world. Chalaturnyk and Li (2004) concluded that steam stimulation, one of the most successful thermal processes, can generate effects in the rock formations during the steam stimulation, reducing the effective stresses through varying the pore pressure, induce oil sands to shear, generate compaction or surface dilation, reducing the strength of the formations around the steam chamber and occasionally can lead the rocks to failure. In order to evaluate the impact of the geomecanics on SAGD (Steam Assisted Gravity Drainage) process in Faja del Orinoco, it is necessary understand the stress state in the studied area as well the formations rock properties and pore pressure behavior during the steam injection to predict wellbore instability, to design the casing shoes, locate the well pairs and to predict accurately the recovery factory as well as the volume of heavy oil that can be extracted in the studied field (Rabe et al. 2008). The purpose of this paper is to provide fundamental geomechanical data set of the area to support SAGD project
1.1 Orinoco Belt
The Orinoco Belt is one of most giant heavy oil reservoir in the world; it constitutes the southern border of Eastern Venezuelan basin. The subsurface rocks date from the Precambriam to the recent and were
affected by several tectonic periods, which gave rise to regional events, the combinations of which favored large stratigraphic accumulations of oil. Regionally, the most interesting intervals are those of the Tertiary. In some locations interest extends to the Cretaceous, important accumulations of heavy oil and bitumen. (Fiorillo, 1983).
