Analysis of movable fluid distribution in a clastic rock reservoir using nuclear magnetic resonance and computed tomography

Studying influence factors of movable fluid distribution is of significance for the development of clastic reservoirs. In this paper, the characteristics of movable fluid distribution in clastic core samples from Tarim Oilfield were studied with nuclear magnetic resonance (NMR) tests and computed tomography (CT) scanning. The movable fluid saturations of each core sample under centrifugal pressure of 3 psi, 10 psi, 50 psi, 100 psi, and 500 psi were measured, respectively. The main factors influencing the movable fluid saturation were analysed. The results show that the movable water saturation is strongly dependent on the centrifugal pressure used. When the centrifugal pressure increased to 100 psi, the movable fluid saturation increased sharply. The CT scanning indicates that the movable fluid saturation is mainly dominated by pore sizes of core samples, and the larger the average pore size is, the higher the fluid saturation will be.