?Houston independent Gastar Exploration Ltd. just reported a striking success in the Deep Bossier play in East Texas. While the Haynesville shale has been dominating news from this prolific section of the U.S. oil patch, the Deep Bossier offers returns that can outshine even those of the celebrated shale.


Gastar’s new well, #1 Belin, encountered 150 feet of net pay in multiple Deep Bossier sands, strongly overpressured sandstone reservoirs that occur basinward of the Jurassic shelf edge. The #1 Belin has the potential to be the best well yet drilled in Gastar’s Hilltop Resort property in Leon County.


“In a lower-price gas environment, the Deep Bossier still generates excellent internal rates of return on a per-well basis,” says Russ Porter, Gastar president and chief executive. Certainly, $12-million wells that can each recover 10- to 20 billion cubic feet of gas equivalent (Bcfe)—or more—can withstand distressingly low commodity prices.


“Our #1 Belin has multiple pays and phenomenal rock, and the highest porosities—up to 25%—that we’ve seen anywhere in the area,” says Porter.


Initially, Gastar plans to complete the two lowest reservoirs, both Lower Bossier sands, in the 18,800-foot well. The test was drilled high on the Hilltop structure; Lower Bossier reservoirs produce better on structure, perhaps because early hydrocarbon migration preserved porosities.


Gastar anticipates high-rate completions from these sands. “We have multiple zones that are each capable of initial potentials between 10- and 15 million cubic feet per day.” A third Lower Bossier sand will remain behind pipe, to be tapped in the future.


Excitement also surrounds two Middle Bossier pays encountered in the well. The Middle Bossier, which occurs from 15,000 to 17,500 feet deep at Hilltop, produces from complex stratigraphic traps. In #1 Belin, the sands were found productive on the downthrown side of a fault that splits the Hilltop structure. The presence of gas in these reservoirs extends potential across a wide swath of Gastar acreage.


Furthermore, one Middle Bossier reservoir present in #1 Belin is the Lanier sand, a pay zone that exhibits characteristics similar to reservoirs encountered in the extraordinary Amoruso Field, which lies directly west across the Navasota River in Robertson County. The coarser-grained Lanier sand could be part of the channel system that carried sediments from the shelf into the basin deeps. Gastar recently made a 21-million-a-day recompletion in its #3 Wildman Trust in the Lanier sand.


“Internally, we have talked about the Belin having the potential to be a 25-Bcfe well,” says Porter. As a yardstick, Gastar’s last six wells have average estimated ultimate recoveries of 10 Bcfe each.


Currently, Gastar produces 20 million net a day from Hilltop, and its gross production is about double that. Its gas volumes will grow significantly in the coming months as it brings the Belin and another new well onstream. Its #7 LOR is currently being drilled, and is expected to reach total depth shortly. It has already encountered two productive Middle Bossier sands, and Gastar is drilling a sidetrack to a location that should encounter thicker reservoirs, based on 3-D seismic interpretation.


This year, Gastar’s base case is to keep one rig drilling at Hilltop on a mixture of Lower and Middle Bossier targets. That equates to three to four wells a year, which barely scratches the surface of its inventory. At 160-acre spacing, it has 135 potential locations on its leasehold. Many of these are multiple-objective tests, with targets ranging from Lower and Middle Bossier to shallower objectives in the Upper Bossier and Knowles limestone.


These days, of course, emphasis is also on lowering capital costs. In the past year, Gastar has driven down its costs for a completed Middle Bossier well to $9.5 million from $12 million. This was achieved mainly through new casing designs that lowered steel costs and drilling days. “This has been a breakthrough for us.” And, that effort has fortified the play’s already strong economics.


If gas prices and capital markets improve, Gastar will consider adding a second rig later this year. “We’re in a hunker-down mode, and we’re being conservative,” says Porter. “But we’re very positive for the long term.”

Comments