ADVANCE FLUID TYPING AND PORE ESTIMATION USING NMR LOGGING TECHNIQUE IN MEHSANA REGION OF CAMBAY BASIN

Abstract

Fluid typing method has extreme importance in the petroleum industry for better understanding of reservoir and its production. The type and mobility of the fluids vary with condition of reservoir with respect the depth and exposure to pressure and temperature. For better production and economic benefits fluid typing is essential. The other major challenge is the large uncertainty in estimating porosity using conventional methods in sequence of silt laminations within shale. Pay zone delineation becomes extremely difficult due to low contrast between pay and non-pay zones in conventional logs. In this work, NMR log is used for characterizing and quantifying fluid properties. With the help of T2 distribution curve, selection of profitable zone became easy as it helped in identifying type of pores and the fluids present of the specific depth with the fluid content. 2DFC-T2D mapping help in estimating the presence of different fluids at each depth and also the bounding of the fluid in different type of pores whether clay bound, capillary bound or free fluid. Integrating conventional logs with NMR helped to predict the impurities like thinly laminated slit, ore minerals like siderite formed by the process of sulphate reduction. At last, the prospective zones are also identified for production of oil