Laborary;
of;
Education;
Ministry;
for;
Geophysical;
Exploration;
and;
Information;
Technology;
in;
Chengdu;
University;
of;
Technology,;
Chengdu,;
Sichuan;
610059,China;
and;
Geochemical;
Surveys,;
BGP;
Inc.,;
CNPC,;
Zhuozhou,;
Hebei;
072750,;
China;