Abstract

One of the hallmarks of certain depositional environments is the lack of covariance between permeability and thickness. Our study of a recent deep-water well offshore East Coast India, indicated such an environment. In addition, it was noted that Kh has poor covariance with inflow from a layer. It becomes possible, then, through orward models, to investigate whether or not pressure disturbance front during the flow period at the time of inflow investigation saw the classic radial flow at a microscopic level. We have noted that in case of some, though not all layers, the pressure front had inflow deviating from the classical radial flow (even when technical water reduction near sandface was not anticipated). Our thesis is that, this is due to radial and vertical variations in formation properties having been encountered by the pressure front, which, in turn, points to vicinity of a boundary to the pressure front. This is the most important insight gained. Possibility of time-lapse production logging allowing for more and more grading of sub layers in a commingled test and thereby better understanding of Reservoir Limit Test (RLT) results under such conditions exists. Additionally we have gained valuable insights that have a bearing upon testing zones.