OREANDA-NEWS. February 01, 2011. Tethys Petroleum Limited ("Tethys" or the "Company) (TSX: TPL) announced that it had commenced drilling of the KBD01 (Kalypso) exploration well in Kazakhstan, reported the press-centre of KASE.

Tethys mobilised a ZJ30 rig to the site and has now commenced drilling on an attractive exploration prospect (named Kalypso) located approximately 50 km to the north-west of the Doris oil discovery. This well has a planned total depth of 4,000 metres and is targeting potential reservoirs at several stratigraphic levels from the Cretaceous to the Permo-Carboniferous. The ZJ30 rig will drill to a depth of 300 metres where the 508mm casing is planned to be set after which the well will be completed using Tethys' larger ZJ70 rig "Telesto" which is currently drilling ahead in the Permo-Carboniferous sequence on the Dione exploration well AKD03. The KBD01 well is the first deep exploration well to be drilled by the Company on the Kul-Bas block which also contains several other attractive prospects.

The Kul-Bas contract area surrounds the Akkulka contract area where the Company has recently made the AKD01 "Doris" oil discovery and where work is currently underway to appraise this oil discovery and explore the surrounding area.

The original terms of the Kul-Bas Exploration and Production Contract involved a six year exploration period with relinquishments and a 19 year production period which could be extended. Tethys recently announced that it had reached agreement with the Kazakh Ministry of Oil and Gas to extend the exploration term by a further two years (until December 2013) without further relinquishments with the amended Contract being expected shortly. The extension to the exploration period gives Tethys additional time to explore this attractive area.