Mainland Resources Inc. is poking around in a portion of the Haynesville Shale in Mississippi that has been largely unexplored. The Houston-based independent said Thursday its Burkley-Phillips No. 1 well on the Buena Vista prospect in Jefferson County has penetrated the top of the target Haynesville at a depth of 19,980 feet.

The well was developed by Mainland to explore the gas potential of this section in a region of Mississippi where the Haynesville is largely unexplored, except for an offset well that was drilled through a 2,000-foot Haynesville section by Chevron in 1981 prior to the application of modern techniques, the company said.

The company is drilling ahead at 20,078 feet on its vertical well and is on course to reach the programmed depth of 22,000 feet. Upon reaching total depth, the well will be logged and the shale section will be evaluated to confirm reservoir parameters and the belief that an extensive natural fracture system exists within the Haynesville. Mainland said it believes that the Haynesville may extend beyond a 2,000 foot vertical section based on technical information gathered to date.

Mainland previously discovered and developed a Haynesville play in the East Holly Field area in DeSoto Parish, LA. It confirmed the field through drilling and completing five Haynesville wells with Petrohawk Energy Corp. and subsequently sold its interest in the Haynesville in a single transaction for more than $28 million to Exco Operating Co., a subsidiary of Exco Resources, while retaining 100% of the shallower zones including the Hosston, Cotton Valley, and Upper Bossier formations.

“Our exploration concept is that the Buena Vista structure has the potential for a significant accumulation of gas, and based on our past experience in the Haynesville Shale, this prospect could result in multiples of reserves and value when compared to our successful De Soto Parish development,” said Mainland CEO Nick Atencio.