Funding for this research was provided by:
China Geological Survey (12120115063201)
National Natural Science Foundation of China (41401605)
National Key Research and Development Program of China (2017YFC1502900)
Article History
Received: 16 March 2018
Accepted: 16 August 2018
First Online: 29 August 2018
Compliance with ethical standards
:
: The authors declare that they have no conflict of interests.