Seismic activity caused by large groups of people moving together is a well known and documented phenomenon.
The focus of the article is that her quake was bigger than other previous man-made quakes during massive events in the same location and is presented as a proof/show of how popular Taylor Swift is and how passionate are their fans. (much wow).
If you think "Fans of X celebrity are very "energetic"" is a news article that should be posted here its fine, its news after all and people seem to like it, but lets not pretend this is a scientific article in any way.