Aside from the occasional fire sale, we really didn't see many oil and gas transactions for a good stretch of time. In recent days, however, the acquisitions and divestitures market (known in the biz as A&D) seems to have finally begun to pick up.

Last Wednesday, Marathon Oil (NYSE:MRO) announced it was selling its stake in the Corrib development offshore Ireland to recent Global Gains pick Vermilion Energy Trust. The final sum paid will vary a great deal, depending on the date of first gas production by Vermilion and its new partners Royal Dutch Shell and StatoilHydro (NYSE:STO). As Shell is the operator, there's not a whole lot Vermilion can do to influence the timetable and lock in the full $400 million on offer. There's also a pretty formidable activist group to contend with here, so Corrib is no cakewalk by any means.

A day later, BP (NYSE:BP) shed an offshore block in Indonesia, passing it to state oil company Pertamina for $280 million. At a production share of 12,000 barrels per day of crude and 100 million cubic feet per day of gas, Pertamina appears to be getting a pretty attractive price on this operated block, which counts CNOOC Ltd. (NYSE:CEO) and Talisman Energy as stakeholders.

Is BP just not that into Indo? Hardly, but the company appears more keenly focused on liquid natural gas and coalbed methane projects in the country.

Rounding out the trio of transactions is today's agreement between Encore Acquisition (NYSE:EAC) and EXCO Resources (NYSE:XCO). Encore's picking up some Mid-Continent and East Texas assets for $375 million in cash. The primary asset in the former area is a waterflood project (a form of enhanced oil recovery), while the latter is centered in the Cotton Valley sands. I have a hard time getting excited about Cotton Valley gas, which is not one of the lower-cost plays around, but the waterflood certainly falls right in Encore's sweet spot, as an acquire and exploit-type company cut from the same cloth as XTO Energy (NYSE:XTO). It's a fine deal for an oil patch player I'm quite fond of.

StatoilHydro ASA is a Motley Fool Income Investor recommendation. CNOOC and Vermilion Energy Trust are Motley Fool Global Gains recommendations. Drill into any of our newsletter services free for 30 days.

Fool contributor Toby Shute doesn't have a position in any company mentioned. Check out his CAPS profile or follow his articles using Twitter or RSS. The Motley Fool has a disclosure policy.