It was only a matter of time. The Wall Street Journal reports that international oil giant Royal Dutch Shell is in talks to buy BG Group , a giant shipper of natural gas with extensive holdings in Brazil’s oil fields. It may be the opening shot of a consolidation war that many have been expecting . The reason, of course, is the collapse of global oil prices over the last year. Still, most expected that if a merger mania were to break out in the energy industry, it would be primarily focused on smaller cash hungry companies that have seen their valuations slashed by the collapse of crude oil prices. A deal between BG, which has a market value of roughly £31 billion ($46 billion), and Royal Dutch Shell, whose value hovers around $193.4 billion, would be a merger of a different order. It would leapfrog Chevron as the second-largest publicly […]