A successful appraisal well in a previously untested northern segment of Mad Dog field in the US Gulf of Mexico has hiked the complex’s resource to as much as 4 billion bbl of oil equivalent in place, rivaling that of Thunder Horse, said BP PLC.

Trinidad and Tobago’s proved natural gas reserves have fallen for yet another year, according to Houston-based consultant Ryder Scott.

Encana Corp.’s US subsidiary will divest its Fort Worth basin Barnett shale producing and midstream assets by early 2012.

The Middle Devonian Marcellus shale in the US Appalachian basin contains 84 tcf of gas and 3.4 billion bbl of natural gas liquids, the US Geological Survey said Aug. 23.

Results of an appraisal well near the Barquentine discovery off Mozambique has added confidence to Anadarko Petroleum Corp.’s plans for a liquefied natural gas plant fed by gas from Offshore Area 1 discoveries. The company has let contracts for pre-FEED studies.

Oil and wet gas plays of all types are revitalizing basins, reducing unemployment, stressing demand for rigs and other services, and reversing production declines in the US onshore Lower 48, speakers said Wednesday at a session leading up to the Summer NAPE exposition in Houston.

The Sea Lion main complex in the North Falkland basin could yield ultimate recovery of 325-434 million bbl of oil, said Rockhopper Exploration PLC.

HRT O&G Exploracao e Producao de Petroleo Ltda., Rio de Janeiro, has spud its fourth exploratory well, designated 1-HRT-4-AM, in the Solimoes basin in northwestern Brazil.

Beach Energy Ltd., Adelaide, booked initial contingent resources of 2 tcf of gas for its Cooper basin PEL 218 permit in South Australia.

Berry Petroleum Co., Denver, estimated that its risked resource potential in the Uinta basin is 65 million bbl of oil equivalent excluding its proved developed reserves in the basin of 11 million boe.