In 2008, Statoil acquired a 32.5% interest in the Marcellus shale gas acreage from Chesapeake Energy Corporation.
The holding covers 1.8 million acres in the Appalachian region of the north-eastern USA.
The acquisition is part of a strategic agreement between the two companies to jointly explore unconventional gas opportunities worldwide.
The agreement covers more than 32,000 leases in the states of Pennsylvania, West Virginia, New York and Ohio. Chesapeake plans to continue acquiring leases in the Marcellus shale play. Statoil has the right to a 32.5% participation in any such additional leasehold.
With this transaction Statoil has acquired future, recoverable equity resources in the order of 2.5-3.0 billion barrels of oil equivalent (boe). Statoil’s equity production from the Marcellus shale gas play is expected to increase to at least 50,000 boe per day in 2012 and at least 200,000 boe per day after 2020.
Both companies believe that the development programme could support the drilling of 13,500 to 17,000 horizontal wells over the next 20 years.
| Typical unconventional gas reservoirs are tight sands, shale and coal bed methane. These reservoirs are often laterally extensive and with low permeability that produces mainly dry natural gas. Shale gas is formed in fine-grained shale rock. In order to produce shale gas, the use of hydraulic fracturing and horizontal well drilling have been essential. The global unconventional gas resource base is estimated at 5 700 billion barrels of oil equivalent (boe) or 32 000 trillion cubic feet (tcf). (source: NPC Global oil and gas study) The US shale gas reserves are estimated at 700 billion boe (3 800 tcf) and accounts for about 47% of total unconventional gas reserves in North America. It is expected that US unconventional gas capacity will grow sharply over the ten next years. |
Horizontal wells with hydraulic fractures are needed in order to establish productivity in shale gas reservoirs.
In a hydraulic fracturiation operation, water and sand under high pressure are injected into the formation in order to extract the gas from the reservoir.
This illustrates a completed shale gas well with hydraulic fractures. (illustration: Statoil)
This illustration shows an example of a shale gas development with several well pad sites. Each well pad has six producing wells.
Multiple horizontal wells per pad limit footprint and impact on the surface (illustration: Statoil).