BURREN Energy, a small London-based company, found its niche in southern Russia and Turkmenistan transporting oil through the landlocked Caspian Sea but has now added oil and gas production to its bow. It has emerged as an upstream partner with a 25% stake in the Nebit Dag concession in western Turkmenistan, where oil production from the Monument-operated Burun field is 12,000 to 13,000 barrels per day, plus interests in small existing fields in the Lower Volga basin in Russia.