Abstract

Lower bandwidth of 3D seismic data always reduces the limits of visibility and its capabilities to detect relatively thinner layers. Moreover, a high NTG environment further masks deterministic acoustic impedance contrast between the two lithologies which results in almost no normal incidence reflection. It is extremely difficult to interpret the intermediate level horizon in such a condition. This paper highlights a case study of Bhagyam field which has been on production since 2012. Main reservoir units are FB1 and FB3 which comprises around 95% of STOIIP. Also, FB1 alone holds ~70% of STOIIP. FB1 reservoir unit has been sub-divided into three zones based on detailed log correlation and depositional understanding of the reservoir units. Dynamic data and Time lapse saturation (RST) data suggests that these three zones possess variable sweep efficiency and connectivity (Figure 1).