Funding for this research was provided by:
China National Scientific and Technical Support Program (2016YFC0801800)
National Natural Science Foundation of China (41430318, 41272276, 41602262, 41572222)
Natural Science Foundation of Beijing Municipality (8162036)
National Geological Survey Program (DD20160266)
Innovation Research Team Program of Ministry of Education (IRT1085)
Article History
Received: 18 July 2017
Accepted: 12 March 2018
First Online: 19 March 2018