Arco Promotes Bowlin to Key Operations Post : People: He will direct all international and most domestic oil efforts. The shift suggests he may be in the running for chairman.

Atlantic Richfield Co. on Monday announced the promotion of Mike R. Bowlin to executive vice president and member of the board of directors as part of a continuing reshuffling of senior management.

The announcement may suggest a change in the ranks of possible successors for the job of Chairman Lodwrick M. Cook, 64, who is to retire in 1995.

Bowlin, 49, had been president of Arco International Oil & Gas Co. and senior vice president of Atlantic Richfield Co. He will be replaced in those posts by Marlan W. Downey, 60, who joined Arco two years ago from Shell Oil Co.

In his new post, Bowlin will assume many of the responsibilities of Ronald J. Arnault, another executive widely regarded as a possible successor to Cook. Those responsibilities include overseeing Arco’s international operations, its oil and gas operations in the Lower 48 states and its coal operations.

Arnault is returning to his former job of chief financial officer. He was the architect of a dramatic financial restructuring in the 1980s that streamlined the company. Though Arnault, 49, is still seen as a contender for the CEO’s job, his chances appear less certain than in the past.

Arnault, whose expertise had been in finance and planning, was moved into operations in 1990 to make up for a lack of practical experience, analysts said. The latest move “is basically saying that his transition or training period is essentially completed,” said Bernard J. Picchi, senior energy analyst at Kidder Peabody & Co. in New York.

Most of all, however, the promotion of Bowlin to Arnault’s old job signals the increasing importance Arco is placing on international operations. Until the last decade, the company depended almost exclusively on Alaska for its oil reserves and had many of its operations on the West Coast.

Though Arco’s international business is still dwarfed by those of companies such as Exxon, Mobil or Shell, under Bowlin’s management it has grown from what one analyst called a “hobby” into a serious business.