Hi there,
In regards to oil & gas M&As activity during the period between January 2018 and January 2019 in the US alone there has been more than 900 deals worth roughly $300 billion as per attached graph.
In addition looking at some the major transactions in the last 10 years it would seem the sector to be quite active as per some of the following deals:
ExxonMobil acquisition of XTO Energies for $41 billion in 2010; Royal Dutch Shell’s acquisition of BG Group for $54.billion in 2016; Saudi Aramco acquisition of SABIC for $69 billion in 2019; Kinder Morgan’s acquisition of El Paso Pipeline Partners, Kinder Morgan Energy Partners, and Kinder Morgan Management for $76 billion in 2014.
Reference
Oil & gas M&A deals for January 2019 total $11.64bn in United States
The biggest ever mergers and acquisitions in the oil and gas industry