Standards of Well Fracturing Measures in Class II Grade B Reservoirs in Water Cut Period

Abstract

The practice of polymer flooding development of Lamadian oilfield in extra high water cut period shows that the initial effects of well fracturing in class II grade A reservoirs is much better than that of class II grade B reservoirs, which means there is a big difference of the fracturing effect between two types of oil layers. Only a few wells of class II grade B reservoirs obtain better fracturing effect. To further improve the development effect of class II grade B reservoirs, the standards of well fracturing measures of such reservoirs in water cut period should be pinpointed. This paper compared the data of 48 fracturing wells of class II grade B reservoirs such as the dynamic production data, well pattern, scale of fracturing, fracturing layers and compound mode before and after fracturing in water cut period. Through analyzing differentiation characteristic of fracturing in different types of oil layers, this paper pinpointed the technology boundary of selection of fracturing wells and selection of fracturing layers of different oil layers in class II grade B reservoirs P II 7-G I 4 + 5 oil layer in water cut period. Refining of the fracturing standards of wells in water cut period provided effective reference and basis for the well-selecting and layer-selecting in class II grade B reservoirs in water cut period, which validly improve the development effect of the wells in class II grade B reservoirs.