UPDATE 1-Gulf Keystone finds oil at Shaikan-1 well

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Oct 6 (Reuters) - Oil and gas explorer Gulf Keystone Petroleum Ltd (GKP.L) said on Tuesday it discovered oil in the upper portions of the Triassic section of the Shaikan-1 exploration well in northern Iraq.

The discovery was in addition to the two to four billion barrels of heavier oil previously announced at various levels throughout the shallower Jurassic intervals, Gulf Keystone said.

The discovery of these high energy, light oil zones within the upper levels of the Triassic significantly improves chances of finding additional light oil targets in the 700 to 1,000 meters still to be drilled, the company said in a statement.

Gulf Keystone, which is focused on Algeria and northern Iraq, said it was planning to install a workover rig on completion of drilling operations so as to start extended testing of the multiple pay zones present in the Shaikan-1 well. Gulf Keystone shares closed at 105 pence on Monday on the London Stock Exchange. (Reporting by Kumar Alagappan in Bangalore; Editing by Vinu Pilakkott)