H.—34.

The following summary gives the number of earthquakes reported felt in New Zealand during the year 1935, and the maximum intensity reported in each month : —

It will be seen that 150 earthquakes were felt in some part of New Zealand during the year 1935. Of these earthquakes, 103 were felt in some part of the North Island, and 54 in some part of the South Island. Seven were felt in both Islands. The following list gives the number of earthquakes in which the maximum intensity reported reached the various degrees of the Rossi-Forel scale : —

The total number of earthquakes reported felt, and the maximum intensities reported in each of the years 1921 to 1935 (inclusive), are as follows : —

The figures in the above table giving the number of reported earthquakes require careful interpretation. In years of major earthquakes, such as 1929 and 1931, many of the numerous aftershocks are liable to be passed unnoticed, while during a period of quiescence there is a tendency for all shocks, however slight, to be reported. This leads to an undue emphasis being placed upon earthquake activity of what is a comparatively quiet period. The great number of earthquakes reported in 1922 is due to the swarm of local shocks which occurred in the Taupo region in the latter half of that year. Also, although there was no major earthquake in 1930, a large number of shocks occurred in that year, due mainly to the continuation of aftershocks of the Buller earthquake of 1929, 17th June.

104

Number o( Earthquakes reported felt. Maximum Month. j Intensity Locality of Maximum. North Island. South Island. Both Islands. ! <R '" F ' SoM> ' 1935. January.. .. .. 7 5 1 11 5 Tokomaru Bay, Hastings. February .. 12 7 1 18 5 ' Puysegur Point. March .. .. .. 8 5 .. 13 6 Hicks Bay. April .... 6 1 .. 7 5 Wanganui, Milford Sound. May .. .. ..16 3 1 18 5 Farewell Spit. June .. . . 10 3 .. 13 5 Taupo. July .. .. 11 9 .. 20 7 Wairakei. August .. .. .. 7 6 1 12 6 Waipiro Bay. September .. 6 6 1 11 5 Whakatane, Lake Grass - mere, Cheviot. October . . .. .. 4 5 .. 9 6 Milford Track (Quinton Huts). November .... 7 3 1 9 5 Wanganui, Paraparaumu, Paekakariki. December .... 9 1 1 9 5 Paekakariki. Totals .. .. 103 54 7 150 7 Wairakei. I

Eossi-Forel Scale. Month. Totals. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 1935. January 1 4 4 2 11 February .. . . .. .. 2 9 6 1 18 March .. .. . • .... 2 (i 4 .. 1 13 April 2 2 1 2 7 May .. .. .. .... 1 9 7 1 18 June 1 3 7 2 13 July .. . . .. .. 1 2 4 8 4 .. 1 20 August . . .. .. .... 1 4 6 .. 1 12 September . . .. .... 1 2 4 3 1 11 October .. .. .. .... 2 4 3 9 November .. .. .... 1 3 3 2 9 December .. .. . . 1 . . 5 1 2 9 Totals .. .. .. 2 16 55 54 19 3 1 150

,ySs. Isaacs j5& SSscs 1921 .. .. 91 8 1929 .. .. 678 10 1922 .. 1,187 8 1930 .. .. 748 8 1923 .... 76 6 1931 .. .. 432 10 1924 .... 70 7 1932 .. .. 313 9 1925 .... 76 8 1933 .. . . 108 7 1926 .. .. 173 8 1934 .. .. 230 9 1927 .. .. 107 8 1935 . . .. 150 7 1928 .. .. 80 8