Abstract
During fluid injection into a multilayered reservoir, a different pressure gradient is generated across the face of each permeable layer. This pressure gradient generates driving forces in the wellbore during well shut-in that causes the injected fluid moves from higher pressure layers to lower pressure layers, a phenomenon known as interwell cross-flow. Cross-flow behavior depends on the initial pressure in the permeable layers and may be referred to as natural cross-flow (identical or natural initial pressures) and forced cross-flow (different initial pressures because of exploitation). Cross-flow may induce sand production and liquefaction in the higher pressure layers as well as formation damage, filter cake build-up and permeability reduction in the lower pressure layers. Thus, understanding cross-flow during well shut-in is important from a production and reservoir engineering perspective, particularly in unconsolidated or poorly consolidated sandstone reservoirs.
论文详情