The oil and gas sector is still an industry with relatively high and predictable returns, even though international crude prices will flatten in the coming decade and then decline, said an expert.

Andy Brogan, Ernst & Young global oil and gas leader, said on Monday in Beijing that despite China's relative economic slowdown, energy demand will rise rapidly with the continued growth of emerging economies, which will offer immense opportunities for oil and gas companies.

Ernst & Young released its latest report on the sector on Monday, covering the top 10 risks and opportunities in 2013 and beyond.