Baobing Shang
Tianjin Branch, China National Offshore Oil Corporation, Tianjin 300459, P. R. China

Xiaodong Han
Tianjin Branch, China National Offshore Oil Corporation, Tianjin 300459, P. R. China

Shuai Li
Department of Earth Science and Engineering, Imperial College, London, the UK

Kouqi Liu
Department of Petroleum Engineering, University of North Dakota, Grand Forks, USA