LONDON -- The shares of BG (LSE: BG) (NASDAQOTH: BRGXF) slipped 9 pence to 1,056 pence during early London trade this morning after the FTSE 100 member named its new chief executive.

The oil and gas major confirmed that Chris Finlayson will succeed Sir Frank Chapman on Jan. 1. Finlayson joined BG from Royal Dutch Shell during 2010 and was appointed to BG's board last year. He currently leads the group's exploration team and major capital projects program.

Andrew Gould, the chairman of BG, said:

The process to appoint Sir Frank's successor early in 2013 has been rigorous and comprehensive and allows for an orderly transition. The Board identified and assessed three internal candidates and a number of external candidates. ... We were unanimous that Chris has the right skills for the next stage of BG Group's evolution, and the delivery of our growth projects.

Finlayson added, "I am excited and honoured to have been asked to lead BG Group. Under Sir Frank, the Group has grown significantly, with resources expanding from 1.2 to more than 17 billion barrels of oil equivalent."

Sir Frank Chapman then said:

"For me the last 16 years has been a fascinating and totally absorbing journey. The greatest reward has come from working with so many talented and committed BG Group people. Who they are and how they go about their work defines BG Group and I thank every one of them for their loyalty and hard work."

Sir Frank's 12 years in charge of an independent BG have seen the exploration side of the old British Gas utility transform into a top-15 FTSE 100 company. During Sir Frank's tenure, BG's operating profit surged from 688 million pounds to more than 5 billion pounds, while the dividend has advanced from 2.9 pence to almost 15 pence per share. Meanwhile, the share price has rallied from 262 pence to reach as high as 1,564 pence during 2011.

This year, however, a shock warning about production delays wiped 17% from BG's share price during the end of October. However, few long-term holders will gripe at Sir Frank's long-term achievements, especially given that the FTSE 100 has fallen 6% during his time as chief exec.

Still, BG's warning this year underscores how even major oil and gas companies can surprise investors from time to time. That's why The Motley Fool has published this free report, which explains the factors you need to consider -- and the risks you might encounter -- when evaluating shares within the resources sector. So if any future news at BG tempts you to acquire more of the company's shares, please click here to read the Fool's exclusive oil and gas report before you hit the "buy" button.