Oil, Gas May

(Bloomberg) — The credit crunch will keep U.S. oil and gas producers from ramping up exploration they do through drillers such as Nabors Industries Ltd., setting the stage for shortages and surging prices when demand recovers.

Chesapeake Energy Corp. and Carrizo Oil & Gas Inc. are among producers spending no more than their cash flow after a collapse in credit markets drove up debt costs. That means they won