Document Type : Review Paper


1 Department of Petroleum Engineering, College of Engineering, University of Baghdad

2 Department of Petroleum Engineering, College of Engineering, University of Baghdad.


Reservoir predictions. It generally encompasses all coring, logging, testing, and sampling procedures. Almost 50 years ago, the evaluation of subsurface formations related to drilling oil wells got involved. It involves all techniques for coring, logging, testing, and sampling in general. It focuses on the process of interpreting logs and how to conduct lab tests that are important for evaluating formations below the surface, including a look at the fluids they represent. The casing is occasionally set to analyze the formations with more accuracy; as a result, this process is also considered. The scientific field of petrophysics of reservoir rocks is interested in researching porous materials' physical and chemical characteristics and the elements of reservoir rocks connected to pore and fluid distribution. Much research on the characteristics of various rocks, including their porosity, permeability, capillary pressure, hydrocarbon saturation, fluid properties, electrical resistivity, self- or natural potential, and radioactivity, has been carried out in recent years. The existence or absence of economic quantities of hydrocarbons in formations penetrated by or around the wellbore is assessed using these qualities and their relationships. This paper's main goal is to evaluate the historical evolution of the most popular methods for calculating petrophysics parameters in the lab and on the ground, mostly based on the researchers' scientists' knowledge of that field.