A stratigraphic corehole in the Mitis River area of Canada’s St. Lawrence Lowlands southeast of Rimouski, Que., has encountered natural gas flows from a permeable and porous zone in the Lower Silurian Sayabec formation at 1,874 m.
Gas analyzed 89% methane, and the 10-m thick zone had measured porosity as high as 20.8% and permeability of 1,624 md, said the operator, Ressources et Energie Squatex Inc., headquartered in the Montreal suburb of Brossard, Que.
Squatex said its Masse-1 corehole encountered “important porous dolomitized limestone zones of hydrothermal origin containing gas,” or hydrothermal dolomite. The company began the stratigraphic core program in 2010 to evaluate the oil and gas potential of its licenses.
Fine-grained rocks of the St-Leon formation act as cap rocks for the gas-bearing horizon, Squatex said. A similar porous horizon was already known outcropping near St-Cleophas in the Matapedia area 20 km east near Quebec’s provincial boundary with New Brunswick, the company noted.
Masse-1 was designed to test a series of seismic amplitude versus offset anomalies indicating the possibility of the presence of fluids and-or porous reservoir rocks near thrusted zones. Squatex said “important gas flows started to occur” when it began coring at 1,847 m.
The company filled the hole with cement because the rig had no flow test capability. Preliminary geophysical interpretation indicates that the areal extent of the prospective zone of AVO anomalies could exceed 20 sq km and contain as much as 100 bcf of gas in place, Squatex said.
The company is evaluating options to finance the continuation of geoscientific work such as new seismic, AVO processing of existing lines, and confirmation drilling.
Squatex’s 656,093 ha of leases in the lowlands include a 70% interest more than 217,370 ha under a joint venture agreement with Petrolympic Ltd., Toronto, and a 28% interest in 8,000 ha that were farmed out to Canbriam Energy Inc., Calgary. Squatex also owns a 70% interest in 431,339 ha in the Lower St. Lawrence under its joint operating agreement with Petrolympic.