Lime Rock Partners, an energy-focused global private equity firm, has completed its third oil service technology investment in 2010 and fourth in the last year. The firm recently closed a NOK 50 million investment in Reelwell, a Stavanger, Norway-based technology company developing a new approach to drilling with unparalleled wellbore cleaning and pressure control capability and greatly extended horizontal reach.

Earlier this year, Lime Rock Partners closed a $10 million commitment to Silixa, a London-based developer of a proprietary system to record acoustic signals along optical fiber for use in the oil and gas and other industries.

It also closed a $6 million investment in TerraSpark Geosciences, a Boulder, Colorado-based developer of seismic visualization and interpretation products. Last year, Lime Rock Partners made a $10 million initial investment in PanGeo Subsea, a St. John’s, Newfoundland-based company commercializing 3D and 4D acoustic imaging technologies for use in the oil and gas, offshore wind, and other industries.

Trevor Burgess, Lime Rock’s managing director based in Aberdeen noted, “Small companies are bringing exciting technology to the oilfield to lower costs, increase efficiency, reduce exploration risks, and make possible the development of previously unexploitable oil and gas reservoirs.”

Established in 1998, Lime Rock manages $3.9 billion of private capital for investment in the energy industry through Lime Rock Partners, investors of growth capital in energy companies worldwide, and Lime Rock Resources, acquirers and operators of oil and gas properties in the US.