Porosity Prediction for Some Geological intervals in the East Baghdad Oil Field Using New Empirical Equations

Abstract

This study examines the evaluation of empirical equations related to primary seismic velocity with density and porosity. The empirical equations have been used in 128 sites based on a seismic grid covering the east Baghdad oil field. The average of density of the geological formations between each seismic reflectors and another (each interval) was extracted from well log data for four wells scattered in the field. Those reflectors were arranged from top to bottom of the studied Formations (Fatha, Hartha, Tanuma, Ahmadi, Shuaiba, and Gutnia Formations). In order to determine the best empirical equations, several previous equations were tested to obtain the best that correspond to the density rates taken from well records. The most suitable equations were used in calculating density for all intervals in the whole field. Using the strong relationship (porosity-density) taken from the well log data, the porosity values for all the studied intervals were found. Later, the porosity and density contour maps for each interval in the whole field were established. The locations of high porosity zones were identified and related to the petroleum distribution in the field.

Keywords

• Density
• East Baghdad oil field
• petrophysical parameters
• porosity
• new empirical equations
• seismic velocity analyses

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