Deep diverting gels for very cost effective waterflood control

Placement of gels in depth is an effective approach to Improving waterflood sweep efficiency, particularly In layered reservoirs. The process can give significant and timely additional oil compared with the waterflood baseline. It can be low cost, and operationally convenient. There are a number of possible approaches to ensuring gel is formed where needed, and nowhere else. In the present case, advantage is taken of the thermal gradient set up when cold water is injected into a hot reservoir (or aquifer). The position of the cold front can be modelled to at least sufficient accuracy to ensure correct gel placement.