Funding for this research was provided by:
the work of Chinese Geological Survey (12120114002101, DD20160268)
the Science and Technique Foundation of Henan Province (182102310001)
the Doctoral Fund of the Henan University of Engineering (2016004)
Article History
Received: 19 July 2018
Accepted: 20 February 2019
First Online: 25 February 2019
Compliance with ethical standards
:
: On behalf of all authors, the corresponding author states that there is no conflict of interest.