Novel Steamflood Proposed to Revive Dutch Giant Oilfield

Pipping, Koos¹, Warren Geoff², Duncan Green-Armytage³ (1) EAGE, KNGMG, Assen, Netherlands (2) SPE, Assen, Netherlands (3) SPE, Muscat, Oman

The Schoonebeek oilfield (onshore NE Netherlands) was abandoned in 1996 after hav­ing produced 40 million m3 (250 mln bbls) of its 160 million m3 (1 billion bbls) STOIIP from 599 vertical wells. Due to advances in heavy oil recovery technologies, Schoonebeek is now a candidate for re-development.

The medium gravity 25 API, 160 cp paraffinic oil is contained in the Bentheim (Lower Cretaceous) reservoir which consists of a 30m thick multi-Darcy shallow marine sandstone.

The structure is a heavily faulted, E-W trending, anticline with a crestal collapse graben. Primary recovery was characterised by early water breakthrough and high (>95%) water cut production and rapid pressure depletion. Consequently, a number of small scale secondary and tertiary EOR methods were employed including cold and hot water injection, wellbore heating, steam injection and in-situ combustion.

The redevelopment opportunity proposes to use a process termed Gravity Assisted Steam Flooding (GASF) which combines low-pressure steam injection with horizontal wells. This 15 million m3 (ca. 95 mln bbls) expectation oil development is envisioned to require the drilling of 57 horizontal wells, both producers and injectors.

This paper will briefly summarise past projects and performance and describe key new enabling technologies including the GASF process, horizontal well design, efficient steam generation options, high temperature / high volume artificial lift options, sand control options, Limited Entry Perforation for steam injection conformance control and subsurface water disposal into depleted Zechstein carbonate gasfields.