Reservoir estimation in the Penobscot 3D seismic volume using Constrained Sparse Spike Inversion, offshore Nova Scotia, Canad

The Penobscot study area is located offshore Nova Scotia, Canada. There are two wells, which penetrate the highest potentially commercial bodies in the Abenaki Formation. In order to investigate the potential for locating additional hydrocarbon reservoirs, well log data was used and the Penobscot 3D seismic dataset was analyzed using Constrained Sparse Spike Inversion. From the well log data, low GR and SP values are an indication of a permeable sand layer, which provides the target zone in this study. Impedance -- porosity crossplots gave the relationship between impedance and porosity, where a low impedance sand layer is correlated with high porosity. It was found that the target sand layer has low impedance, a feature recognizable from the inversion results. The porosity of the whole sand layer calculated by the linear function from the relationship between impedance and porosity. The calculation of thickness of this sand layer from maps representing different impedance intervals provided numeric evidence to show there is a low impedance sand layer in the well L-30. The pore thickness map results indicate there is greater pore thickness in well L-30 than B-41. It appears that the company drilled at the optimal location for the initial (L-30) well, and tested the extent of potential reservoir rock with the second (B-41) well. The potential reservoir is apparently fairly small, and restricted to the area around L-30. There may or may not be value in testing another location across a fault, but the rock behind the fault is likely not as high quality as at L-30 and the high-quality regions are small in size and not connected.