The selloff in crude prices has bruised energy companies big and small, but none have felt the pain worse than the nation’s heavily indebted oil drillers. Shares of small, North America-based oil and gas producers that loaded up on debt during times of high oil prices have plunged in the past month, in some cases losing half their market value or more. Shares of Goodrich Petroleum Corp. have plunged 87% from their peak in June and 49% in the past month. Energy XXI Ltd. ’s stock is down 51% in a month. Halcon Resources Corp. has fallen 36% in that time. In the years before 2014’s oil-price crash, these and other companies sold bonds and took out loans to fuel rapid growth in new and often costly fields across the U.S. That borrowing was easier to stomach when oil prices were $100 a barrel, but with U.S. crude […]