New Brunswick shale results perplexing

Dec. 6, 2010
Low recovery of frac water and natural gas from two horizontal wells in the Frederick Brook shale near Elgin, NB, is “unexpected and perplexing,” said Corridor Resources Inc., Halifax, NS.

By OGJ editors
HOUSTON, Dec. 6
-- Low recovery of frac water and natural gas from two horizontal wells in the Frederick Brook shale near Elgin, NB, is “unexpected and perplexing,” said Corridor Resources Inc., Halifax, NS.

The Green Road B-41 well has recovered 1,758 cu m or 10% of frac fluid and no gas to date, and Will DeMille G-59 has recovered 805 cu m of frac fluid or 4% of that pumped and negligible gas. Apache Canada, operator pursuant to a joint venture program with Corridor, is running extensive analysis to determine why the wells have so responded, Corridor said.

Corridor also reports that Apache and Corridor have agreed to conduct tests on the South Branch G-36 oil well.

Apache drilled the wells in mid-2010. Both yielded strong gas shows in the horizontal section while drilling with high mud weights that averaged 1,350 kg/cu m at B-41 and 1,450 kg/cu m at G-59.

Five slickwater fracs were completed in each well with the fracs averaging 230 tonnes of proppant and 3,560 cu m of water. The final frac in the “silty interval” of the Green Road B-41 horizontal well is 630 m from the silty interval of the Green Road G-41 vertical well drilled by Corridor in 2009. That interval in the vertical G-41 well was fraced with propane in 2009 and produced 42.4 MMscf over 185 hr, peaking at 11.7 MMscfd with a final rate of 3.0 MMscfd at about 700 psi.

Steps are being undertaken to recover additional amounts of frac water which could encourage the flow of gas into the wellbore, Corridor said.

“Although the well response to date is perplexing, it is important to recognize that the evaluation of the development potential of the Elgin shale gas resource play is in its early stages,” Corridor noted.