Modelling gas hydrate production potential in the Hikurangi margin

A TOUGH + HYDRATE flow model analogous of hydrate deposits in the Hikurangi margin has been constructed using the best available estimates of permeability, porosity and hydrate saturation. Seismic velocity and AVO analyses have been used to develop this model. Production rate forecasts were made in a single well model with homogeneous properties. In this forecast, the system was depressurised by producing gas from an underlying free gas zone included in the model. Production of 4.6 Bscf (130 × 10 6 m 3 ) of gas was achieved from the well over 20 years with average flow rates of 0.65 MMscf/day (0.213 m 3 /s).