THE KURRAJONG EARTHQUAKE. 83 



The KURRAJONG EARTHQUAKE of AUGUST 15th, 



1919. 



By Assistant-Professor Leo A. Cotton, m.a., d.Sc 



[Read before the Royal Society of N. S. Wales, July 6, 1921.^} 



The earthquake described in this paper occurred on Friday 

 15th August, 1919 at 8*23 p.m. Sydney standard time. The 

 shock was distinctly felt throughout the city and suburbs, 

 though not noticed by all persons. It was not felt in this 

 area by people who were moving about at the time. 



Earthquakes are relatively rare in the Sydney district, 

 and no systematic study of their occurrence has yet been 

 attempted. The first Seismological Committee of the 

 Australasian Association for the Advancement of Science 

 tabulated the earthquakes of Australasia for the period 

 1880 to 1891, but this good work has not been kept up to 

 date.< 5 > 



In the interval mentioned four earthquakes were noticed 

 which affected the Sydney district. Two of these appear 

 to have originated in the Southern District, the particulars 

 indicating seismic foci near Yass in one case and near Lake 

 George in the other. 



A summary of the chief features of these is given as 

 follows: — 



Yass Earthquake. 



Date. Intensity at Yass. Intensity at Sydney 



30th November 1886. VII. IV. 



Lake George Earthquake. 



Date. Intensity at L. George. Intensity at Sydney. 

 6th July, 1888. III. to IV. III. 



