Cephy: a stand-alone, free and open-source toolkit for hydrocarbon in place evaluation by ordinary kriging

Abstract Cephy is a software toolkit written in Java that enables the user to perform spatial interpolation of subsurface data by ordinary kriging. Key features of the software include data exploration by map plot with symbol dimension proportional to the magnitude of the property at a given location; variogram modeling and interpolation of petrophysical properties; as well as oil in place estimation per area unit throughout the reservoir. Cephy enables the user to define the tolerance and the minimum number of pairs required to validate the experimental variogram of the corresponding lag distance when learning the relationship between geolocated data. The software is entirely made of a graphical user interface for adjusting the variogram modeling parameters and visualizing the subsequent interpolationally-generated map. Cephy is applied on Kinkasi reservoir in Kinkasi field (Coastal basin of DR Congo) to demonstrate its functionalities. The result supports a better understanding of oil distribution throughout the reservoir and can be used as a baseline for the suggestion of new infill drilling locations.