* Johan Sverdrup field may be linked to Geitungen find
* Link could modestly reduce costs - analysts
* Det Norske shares up 3.7 pct (Adds analysts, detail, shares)
By Victoria Klesty
OSLO, Aug 27 The giant Johan Sverdrup oil field in the North Sea may be connected to another recent discovery, potentially reducing exploration and production costs for its owners, led by Norway's Statoil.
"Well data indicate that there probably is communication between the two discoveries," Statoil said on Monday, referring to Johan Sverdrup and a recent find on the Geitungen prospect.
The state-controlled oil firm estimated Geitungen, part of production licence 265, contains 140-270 million barrels of recoverable oil equivalents (boe).
When the discovery was announced on Aug. 17, its reserves were estimated at 100-300 million boe by smaller player Det Norske, which holds 20 percent of licence 265. "If Geitungen and Johan Sverdrup are connected then it may reduce exploration and production costs, but I do not think it is likely that we are going to see big drops in per barrel costs," said Christian Yggeset, analyst at Arctic Securities.
He added the find was a very important asset for Det Norske, which saw its shares rise 3.7 percent to 94.15 Norwegian crowns by 0915 GMT, outperforming the Oslo benchmark index. Statoil shares were up 0.5 percent at 147.6 crowns.
Johan Sverdrup was one of the world's biggest oil discoveries last year and stakeholders Statoil, Lundin Petroleum, state-owned Petoro, Det Norske and Maersk are in the process of identifying its exact size and how much each of them might be entitled to.
The field is currently estimated to hold 1.7-3.3 billion barrels of oil.
The Geitungen prospect was drilled approximately three kilometres north of the Johan Sverdrup discovery.
Oil was also proven in the underlying basement rocks, which is regarded as a possible future upside in connection with the development of the area, Det Norske said.
Statoil has a 40 percent stake in licence 265, while Petoro has 30 percent and Lundin Petroleum 10 percent.
"Johan Sverdrup is a field with very low development and operating costs," said Handelsbanken analyst Anne Gjoen. "Johan Sverdrup is ... the most positive thing that has happened on the Norwegian continental shelf in almost a decade and then this adds even more to it."
Statoil said on Monday it would give a volume range for Johan Sverdrup at "a later stage", adding it planned to drill about 8-12 wells in the greater Utsira High area in 2012-14.
Production at Johan Sverdrup is expected to start in late 2018.
Separately on Monday, Lundin Petroleum said it had drilled an appraisal well in the neighbouring production licence 501, on the north eastern part of the Johan Sverdrup discovery, confirming "excellent reservoir properties".
Lundin Petroleum has a 40 percent stake in licence 501, while Statoil has 40 percent and Maersk 20 percent. (Additional reporting by Henrik Stolen; Editing by Dan Lalor and Mark Potter)