1. Department of Geotechnology, Faculty of Technology, Khon Kaen University, Khon Kaen, 123 Moo 16 Mittapap Rd., Nai-Muang, Muang District, Khon Kaen, 40002, Thailand
2. Department of Geology and Geophysics, Texas A&M University, College Station, Texas, 77843-3115, USA,