UPDATE 1-Nautical finds more oil at Kraken, shares soar

* Sidetrack well finds substantial column oil

* Shares gain 48 percent (Adds detail, share price)

LONDON, Sept 21 (Reuters) - British oil explorer Nautical Petroleum NPE.L said it found a substantial column of oil at a sidetrack well drilled at the Kraken oil field in the central North Sea, sending its shares soaring.

Nautical said on Tuesday the additional well, drilled to the west of the original well, found two zones of good quality oil with oil saturation of 90 percent and no oil water contact.

“The sidetrack has encountered a substantial oil column, which will result in the reclassification of significant oil volumes from prospective to contingent resources,” said Chief Executive Steve Jenkins.

Shares in Nautical, which have gained 369 percent since the beginning of the year on the back of significant discoveries at Kraken and Catcher, were up 48 percent to 329 pence at 1050 GMT, valuing the company at around 288 million pounds ($446.8 million). [ID:nLDE6640AA] [ID:nLDE6880ZK]

Nautical, which owns a 35 percent equity interest in the block, said earlier in September the sidetrack well was targeting resources of 114 million barrels of oil.

Reporting by Sarah Young; Editing by Victoria Bryan