Min-Chien Tsai, Central Weather Bureau, Taiwan, Seismological Center, Taipei, Taiwan, Yang Ying-Hui, Southwest Petroleum University, Chengdu, China, Jyr-Ching Hu, National Taiwan University, Department of Geosciences, Taipei, Taiwan and Adi Maulana, Hasanuddin University, Department of Geological Engineering, Makassar, Indonesia