We would like to thank Zhiguang Xue, and Junzhe Sun for their constructive
suggestions. The first author thanks China University of Petroleum-Beijing
for supporting his visiting to the Bureau of Economic Geology at UT Austin.
The work is partially supported by Youth Science Foundation of China
University of Petroleum at Beijing (Grant NO. 01jb0508) and Science Foundation
of China University of Petroleum-Beijing (Grant NO.2462015YQ0604).