Wonder why Exxon Mobil Corp. is after Celtic Exploration Ltd. which it agreed this week to buy for $2.6-billion?

Here’s an idea: they stand to make a lot of money.

Look at Celtic’s investor presentation and you will see a natural gas company: 75 per cent of its production is gas. But look at one of its most promising plays, and you might find something else. Celtic has 42,000 net hectares in Alberta’s Kaybob Duvernay shale. It figures it has space to drill 650 to 1,300 wells there.