Chevron’s got some headaches to deal with: In Nigeria it faces ongoing hostilities from local thugs, and in Ecuador, it’s fighting claims that its Texaco unit engaged in toxic-waste dumping.So why not engage in a little retail therapy? In February, Chevron wrapped up its $3.2 billion acquisition of Pennsylvania’s Atlas Energy, adding to its growing portfolio of natural gas operations. It also bought 200,000 acres of the Duvernay shale gas formation in Alberta, Canada. Expect the buying to continue: Chevron says it will boost capital spending 20% this year to $26 billion. —P.N.