Khulud Tight Gas Production Tests Eyed Later this Year

Production tests targeting Petroleum Development Oman’s (PDO) Khulud tight gas fields in North Oman are slated to commence later this year, marking a key step in the majority government owned company’s efforts to harness the potential of unconventional gas reservoirs within its vast concession. Nine appraisal wells have been drilled so far, alongside extensive seismic acquisition and hydraulic fracturing (fraccing) operations designed to help the company gain a better understanding of what is potentially the world’s deepest tight gas reservoir.

An eventual breakthrough in commercialising Khulud’s tight gas potential ensures a place for PDO, alongside energy major BP and the wholly government owned Oman Oil Company Exploration and Production (OOCEP), as pioneers in the Sultanate’s nascent efforts in the development of its tight gas reservoirs. While BP is gearing to develop the tight gas potential of the Khazzan field in its Block 61 concession in central Oman, OOCEP is poised to bring its Block 60 tight gas field into development later this year or early next year.

“For several years, we have been involved in tight gas development particularly in Khulud, which has some of the deepest tight gas reservoirs in the world,” said Raoul Restucci, PDO’s Managing Director. “In (the third quarter) of this year — meaning in the next few months — we will be tying in several wells that we have drilled. We are into Well No 10 now, which includes horizontal wells that we frac. So we’re looking forward to production tests later this year,” he added in comments to the Observer.

Khulud’s ‘tight’ gas characteristics require the use of unconventional — and expensive — techniques to unlock the gas and make it flow to producing wells. Hydraulic fracturing — or fraccing — will be needed to make the gas, trapped in tight rock of extremely low permeability, flow from the reservoir into production wells. Compounding the challenge of producing this gas is the depth at which the reservoirs in Oman are often located — typically in excess of 5.5 kilometres — far deeper than tight gas found elsewhere in the world, say experts.

PDO’s quest to unearth the deep tight gas potential of its Block 6 concession gained pace in 2009 when it launched an ambitious exploration programme targeting previously untapped reservoirs — both conventional tight gas plays as well as deep unconventional gas resources. In 2011, the company said it would drill and test up to 30 tight gas wells in northern Oman over the next four years, alongside extensive 3D seismic data acquisition. It also outlined plans to drill wells to test new gas play concepts in the southern and central parts of its concession.