Enlarge / Taylor Swift during her Eras Tour. Crowd motions likely caused mini "Swift quakes" recorded by seismic monitoring stations. (credit: Ronald Woan/CC BY-SA 2.0) When mega pop star Taylor Swift gave a series of concerts last August at the SoFi Stadium in Los Angeles, regional seismic network stations recorded unique harmonic vibrations known as "concert tremor." A similar "Swift quake" had occurred the month before in Seattle, prompting scientists from the California Institute of Technology and UCLA to take a closer look at seismic data collected during Swift's LA concert. The researchers concluded that the vibrations were largely generated by crowd motion as "Swifties" jumped and danced enthusiastically to the music and described their findings in a new paper published in the journal Seismological Research Letters.