HOUSTON — Oilfield services company Baker Hughes Inc. said Monday that it will buy BJ Services Co. in a cash-and- stock deal valued at $5.5 billion, a move that could kick off further consolidation in the industry.

The combined company will provide customers with a one-stop shop for a variety of oilfield services, and allows Baker Hughes to diversify its product offering and to compete better with rivals Schlumberger Ltd. and Halliburton Co.

This deal could be the first of many acquisitions in the industry, said Chris Sheehan, director of M&A Research at IHS Herold Inc. Sheehan said small-to midsize companies that specialize in international deepwater drilling and production oil services are particularly well positioned to be acquired.

“For companies to gain a competitive or technical edge . . . players in this sector would find it advantageous to seek strategic acquisitions,” Sheehan said in a phone interview. Following the move by Baker Hughes, Sheehan expects further consolidation in the oilfield services sector, especially among companies focused in unconventional shale gas.

These players specialize in accessing hard-to-reach shale gas fields through such methods as pressure pumping.

Notably, Baker Hughes will gain BJ Services’ pressure pumping business, which will help clients with such unconventional gas and deepwater fields, said Chad Deaton, Baker Hughes chairman, president and CEO.

“It will better position us to drive international growth and to compete for the growing large integrated projects by incorporating pressure pumping into our product offering,” he said. Integrated oil companies are active in all phases of the business including production, refining, transportation and marketing.

The acquisition is expected to produce $75 million in cost savings for Baker Hughes in 2010 and $150 million in 2011, and add to earnings per share in 2011.

The deal is valued at $5.5 billion based on Friday’s closing prices. BJ stockholders will receive 0.40035 shares of Baker Hughes and $2.69 in cash for each share they own. The deal represents a 16.3 percent premium to BJ’s $15.43 Friday closing stock price, the companies said.

Shares of Baker Hughes fell $3.64, or 9.6 percent, to close Monday at $34.45. BJ Services shares jumped 63 cents, or 4.1 percent, to $16.06.

BJ’s shareholders will have an approximately 27.5 percent stake in Baker Hughes once the acquisition closes, and two BJ services board members will join Baker’s board.