Pliocene gas gauged at Mnazi Bay, Tanzania

May 9, 2012
Maurel & Prom, Paris, has plugged the Ziwani-1 wildcat on the Mnazi Bay concession onshore Tanzania after it tested natural gas from a Pliocene limestone, said partner Wentworth Resources Ltd., Dar es Salaam.

Maurel & Prom, Paris, has plugged the Ziwani-1 wildcat on the Mnazi Bay concession onshore Tanzania after it tested natural gas from a Pliocene limestone, said partner Wentworth Resources Ltd., Dar es Salaam.

Drilled to 2,671 m, Ziwani-1 drillstem tested at an unstable 7.2 MMscfd of gas with as much as 973 psi wellhead pressure on a 36/64-in. choke from a clean limestone at 1,106-09 m with 17% porosity and 78% hydrocarbon saturation. The zone has not been previously encountered on the block, and test data analysis indicate potential resource volumes to be noncommercial.

The well also penetrated several Oligocene-Eocene sandstone intervals, but logs indicate them to be water-bearing.

The rig will move to work over and perform extended well tests on the MB-2, MB-3, and MS-1X wells in Mnazi Bay gas field. Then the group will use it to drill a second exploratory well on the concession (OGJ Online, Feb. 3, 2012).