Sekiya Seikei (関谷 清景, 28 January 1855 - 8 January 1896), alternatively Sekiya Kiyokage, was a Japanese geologist, one of the first seismologists, influential in establishing the study of seismology in Japan and known for his model showing the motion of an earth-particle during an earthquake.Sekiya took up the study of the earthquakes in 1880.