On September 11, 2018, Diego Melgar, an internationally renowned seismologist and assistant professor of the University of Oregon, USA, came to the Center for Satellite Navigation and Positioning Technology of Wuhan University at the invitation of Professor Geng Jianghui. Dozens of teachers and students from the Center for Satellite Navigation and Positioning Technology and the College of Surveying and Mapping of Wuhan University participated in the report.
The title of the report is "When do large earthquakes know they are going to be large?". The report focuses on "how to determine the magnitude of an earthquake quickly and accurately" and covers the following issues: magnitude saturation, focal time function, high sampling GNSS, slip purse width, and application of machine learning methods. Diego had full exchanges with the teachers and students on related earthquake issues. The discussions were heated and questions were raised continuously.

(Correspondence: Li Chenghong)