The influence of tectonic forces on the coupling ratio of sand Z-600, Keutapang formation, North Sumatra Basin.

The tectonic mechanism is a mechanism that involves tectonic conditions in the area which affects the dynamics of poroelasticity. Elastic modulus in the porous medium will go through change along with fluid dynamics. The loading factor in the tectonic mechanism is followed by the tectonic forces. The aim of this study is to learn the impact of a tectonic mechanism on the coupling ratio during oil production and water injection. The objective zone of this study is a part of thrust fault regime, which is changed to be strike-slip fault regime. The sand reservoir of Z-600 is in the transition condition so that the dominance of S_V and S_hmin has a strong influence on a coupling ratio change. The fluid dynamics occurring during this period are oil production and water injection. Observations were made on mechanical properties and pore pressure changes. The coupling ratio estimation starting from 1994 until 2017 refers to a historical production matching, which demonstrates a rock strength response in the variation of existing tectonic regime position. Mohr diagram analysis was done, based on the Coulomb failure criterion. It reveals that pore pressure change is not always equal to the change in stress difference or deviatoric stress, due to the nature of irreversible porosity change during fluid dynamics. The horizontal stress might cause shear-tensile failure, it initiates a sanding problem potential. [ABSTRACT FROM AUTHOR]