UPDATE 1-Cadogan resolves GPS gas plant dispute

* GPS to seek alternative buyer or keep plants

* Cadogan to get $37.5-38.5 mln payment

* Shares close up 11.1 percent (adds detail)

LONDON, Oct 15 (Reuters) - Ukraine-focused oil firm Cadogan Petroleum (CADP.L) said it had settled a dispute over gas treatment plants it ordered from oil technology group Global Process Systems, sending its shares up by as much as a third.

Under the settlement, Cadogan will no longer take delivery of the two plants, which will instead be sold to another buyer or taken into stock by GPS, London-listed Cadogan said on Thursday.

GPS will pay Cadogan $38.5 million if an alternative buyer is found within 10 months, or $37.5 million if the plants remain unsold beyond that deadline.

Cadogan shares closed 11.1 percent higher at 20.25 pence, having earlier risen by as much as 34 percent.

Cadogan had ordered the plants under a previous management team, and had paid GPS about $38 million of a total purchase price of $54.5 million, a spokesman for the company said.

(Reporting by Myles Neligan)