Bulk modulus which relates seismic attributes to rock and fluid properties is considered as animportant parameter for seismic reservoir characterisation workflows, and can provide usefulinformation for such studies. However, its measurement and modelling approaches are yet tobe sufficiently addressed and discussed especially for carbonate rocks. In this research, in orderto provide more information about bulk modulus, nine samples from a carbonate oilfield weresubjected to static and dynamic investigations under dry and saturated conditions. Then, thedynamic modulus was calculated using well log data and ultrasonic measurements. In order toobtain static data, multi-stage triaxial compression tests were performed on the vertical plugsextracted from conventional cores taken at different selected depths. The results showed thatstatic and dynamic bulk moduli follow similar trends, although the value of dynamic modulusis usually higher. Furthermore, several empirical relationships based on simple linear regres-sion and forward and backward stepwise multiple linear regressions were developed to relatemeasured static and dynamic bulk moduli for the given field, then proposed equations wereevaluated by ANOVA analysis. Besides, dry and saturated bulk moduli were modelled using Xuand Payne rock physics model. Here, saturated bulk modulus was modelled using either dynamicor static dry bulk moduli within the Gassmann’s theory. It is observed that Gassmann’s equationgives a more accurate result using dynamic data rather than static ones. The poor Gassmann’sequation prediction under static condition could be attributed to microcracks in the samplesand the uncertainty associated with this theory for complex pore geometry. The outcomes of thisstudy can, furthermore, provide the necessary information and relationships for rock physics (e.g.shear wave estimating and fluid substitution modelling) and geomechanical (e.g. CO2injectionand compaction forecast) studies for exploration and development programs.

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