Zhejiang Univ, Dept Earth Sci, Hangzhou 310027, Peoples R China.^Second Oil Recovery Plant of Daqing Oilfields Co, Daqing 163414, Peoples R China.^Daqing Commun Ctr, Longnan Telephone Stn, Daqing 163410, Peoples R China.^Daqing Logging & Testing Serv Co, Daqing 163411, Peoples R China.^Wuhan Polytech Univ, Dept Civil Engn, Wuhan 430023, Peoples R China.