Langfang;
Branch,;
Research;
Institute;
of;
Petroleum;
Exploration;
and;
Development,;
Langfang,;
Hebei;
065007,;
China;
School;
of;
Resource;
and;
Earth;
Sciences,;
China;
University;
of;
Mining;
&;
Technology,;
Xuzhou,;
Jiangsu;
221008,;
China;
School;
of;
Energy;
Resources,;
China;
University;
of;
Geosciences,;
Beijing;
100083,;
China;