Abstract:

Water production is one of the key problems encountered in development of gas reservoirs. Water produced from carbonate gas reservoirs can be divided into condensate water and formation water, and the latter can severely influence normal recovery of gas. There are three modes of water production including water production from gas producing intervals, vertical water breakthrough and rising gas-water contact. Although the carbonate gas reservoir has a unitized pressure system, pores are generally characterized by their heterogeneity with three secondary porosity zones, due to the modification made by tectonic movement and diagenesis. As a result, gas-water contact varies greatly between wellblocks, and there will even be a wide unsteady gas-water transition zone, thus formation water production can easily occur during dynamic development.

Key words: carbonate gas reservoir, formation water production, heterogeneity, gas-water transition zone