Tethys Tidies as It Tests in Tajikistan
Wednesday 14 September 2011
(Press release) – Toronto-listed Tethys Petroleum is looking into ways to speed the cleanup of its East Olimtoi exploration well EOL09 as it continues testing operations.
Testing operations are underway on the East Olimtoi EOL09 exploration well located south of the town of Kulob some 10 km north of the Afghan border. This well reached a total depth of 3,765 m in the Akdzhar formation and testing operations are being undertaken on the overlying Bukhara and Alai formations.
Currently the well is flowing a mixture of completion brine and oil from the upper Alai sandstone interval, this oil being of good quality with an API gravity of approximately 36°. The current section open to testing includes this upper Alai sandstone unit as well as the lower Alai limestone interval and the upper part of the Bukhara formation. The well was drilled with heavy drilling fluid (weighted with barite), which was required to control the well when it intersected the upper Alai reservoir. Barite is currently being observed in the flow lines which the company believes is also inhibiting flow at present. It is anticipated that the well will clean up in due course, however the cleanup period may take some time. The Company is currently evaluating methods of speeding up the clean up of this well including acidisation or nitrogen-lifting using coiled tubing, subject to availability of equipment.
There are two further sandstone zones in the Alai formation which appear oil bearing based on wireline logs and which will be tested after a stable and representative flow rate has been achieved from the upper Alai sandstone unit. The lower part of the Bukhara interval was also tested but was found to have low permeability at this location although with the potential for production in future wells using production enhancement techniques such as hydraulic fracture stimulation. Mobilization of such equipment to Tajikistan would take a significant amount of time, as such the company has chosen to focus on the upper zones of this particular well at this time.
The Persea 1 exploration well, located near the town of Kurgon-Teppa is progressing within the 12"¼ hole section. This well is primarily targeting the Bukhara limestone formation in a four-way dip closed structure with the overlying Alai formation forming a potential secondary target. The planned total depth of this well is 2,700 m and it is expected that this will be reached in October 2011.
Data collection for the gravity, gradiometry and magnetic aerial survey carried out over the 35,000 km² Bokhtar Production Sharing Contract Area has now just been completed. This will provide additional and more aerially extensive data to complement the existing seismic acquisition with the final processed data and results expected in Q4 2011.