Effect of petrophysical and sedimentological properties on the heterogeneity of carbonate reservoirs : impact on production parameters

Abstract

The carbonated reservoirs, concentrated mainly in the Middle East, contain about 50% of the world’s hydrocarbon resources, where the considerable challenge they represent for the sustainable development of oil resources and the challenges posed by their production are commensurate with this potential. The characterization of these reservoirs through the control of their heterogeneities makes it possible to reduce the uncertainties on the quantification of their reserves inorder to improve their productivity as well as their recovery rate. The recovery rates obtained today on the main carbonated fields are mainly related to their sedimentary deposits and the very varied climatic conditions, resulting in a very heterogeneous geology and represent difficult challenges to overcome where the permeability is not the same, only condition for better production. This can vary from less than 10% to more than 40% on medium permeability deposits (10 to 100 md). To these parameters is added the diversity of recovery mechanisms and development patterns, on which the dynamic behavior of the deposit depends, which are far from being conditioned by the single permeability factor. Currently, in Algeria, the valorization of carbonated reservoirs, mainly located at the level of South Eastern Constantinois reservoirs where most of these reserves remain unexploited, are among the strategic and priority objectives, because of their complexity. Indeed, the study of stratigraphic heterogeneities, obtained from logging data and core studies, applied to South-Eastern Constantinois reservoirs (Algeria), shows that the results play an important role in the development of carbonate reservoirs production in this area