Rock Physics Characterization of Light Tight Oil Plays

Recently Petroleum Development Oman (PDO) embarked on a campaign to explore the existence, extend and commerciality of a number of light tight oil plays. One of them exists in the Pre-Cambrium group of south Oman, the other one in the Cenomanian source rock formation of North Oman. Both Formations are tight with porosities ranging from 0 to 10% and permeabilities ranging from 0.001 to 0.4 mD. In order to access these potentially recoverable volumes, these and future wells need to be stimulated via hydraulic fracturing. The geomechanics team was involved at the early stage of the exploration wells to plan deign the data acquisition program for the purpose of geomechanics assessment. This includes wire line logs, laboratory test and other field measurements such as micro-frac. Using the acquired log and laboratory data, 1-D calibrated geomechanical models were built on a well by well basis for four vertical wells. The objective of the Geomechanical analysis, carried out for this project, was to provide input to the hydraulic fracturing design for each well. The main assessed parameters were: stress profile, Elastic Moduli (Young Modulus and Poisson ratio), fracture toughness and rock strength. All these parameters were derived from the acquired logs and calibrated against the laboratory measured data,