9/56 YEAR CYCLE: NEW ZEALAND EARTHQUAKES

APPENDIX 7

9/56 YEAR CYCLE: NEW ZEALAND EARTHQUAKES

Appendix for the paper 9/56 Year Cycle: Earthquakes & Volcanoes.

The Institute of Geological & Nuclear Sciences presented a map of New Zealand major earthquakes (mag =>6.9) from 1840 to 2010, which were 'notable shallow earthquakes' (generally less than 30 kms depth). Of the 21 given, 12 showed up in the year beginning January 1 of those years in the 9/56 year grid shown in Table A (significant p < .01). More remarkably, 13 major New Zealand earthquakes happened during the 1840 - 1950 era, of which 10 appeared in Table A in contrast to the 3.3 that could have been expected chance.

Seasonality can appear in patterns of NZ earthquakes. In the following 18/56 grid, five New Zealand quakes occurred in the 2.7 months to March 10 with one anomaly on June 17, 1929.

Sq 03		Sq 21		Sq 39		Sq 01
				1855 0123	+ 18	1873
1875	+ 18	1893 0212	+18	1911	+ 18	1929 0309 0617
1931 0202 0213	+ 18	1949	+ 18	1967	+ 18	1985
1987	+18	2005

In the ensuing 18/56 grid, four New Zealand quakes took place in the 2.7 months to October 20, with an anomaly on June 24, 1942.

				Sq 52				Sq 32
								1848 1016
1832	+ 18	1850	+ 18	1868 1019	+ 18	1886	+ 18	1904
1888 0901	+ 18	1906	+ 18	1924	+ 18	1942 0624 0802	+ 18	1960
1934	+ 18	1962	+ 18	1980	+ 18	1998	+ 18	2016

Table A 9/56 YEAR CYCLE: NZ QUAKES 1840 - 2009 (mag =>6.9) Year beginning January 1
Sq 52	Sq 05	Sq 14	Sq 23	Sq 32	Sq 41	Sq 50	Sq 03	Sq 12	Sq 21	Sq 30	Sq 39	Sq 48	Sq 01
										1846	1855 0123	1864	1873
			1839	1848 1016	1857	1866	1875	1884	1893 0212	1902	1911	1920	1929 0309 0617
1868 1019	1877	1886	1895	1904	1913	1922	1931 0202 0213	1940	1949	1958	1967	1976	1985
1924	1933	1942 0624 0802	1951	1960	1969	1978	1987	1996	2005
1980	1989	1998	2007 0930 1220
The 56 year sequences in the table are separated from each other by an interval of 9 years. Years in bold contained major NZ earthquakes in the year commencing January 1. Source of Raw Data: Institute of Geological & Nuclear Sciences

Higher significance could be achieved applying an 18/56 year cycle, as shown in Table B. Nine major New Zealand earthquakes happened in the ensuing 18/56 year grid, where as about 2.6 could have been expected by chance.

Table B 18/56 YEAR CYCLE: NEW ZEALAND QUAKES 1840 - 2009 (mag =>6.9) Year beginning January 1
Sq 23		Sq 41		Sq 03		Sq 21		Sq 39		Sq 01		Sq 19
								1855 0123	+ 18	1873	+ 18	1891
1839	+ 18	1857	+ 18	1875	+ 18	1893 0212	+ 18	1911	+ 18	1929 0309 0617	+ 18	1947
1895	+ 18	1913	+ 18	1931 0202 0213	+ 18	1949	+ 18	1967	+ 18	1985	+ 18	2003 0822
1951	+ 18	1969	+ 18	1987	+ 18	2005
2007 0930 1220
The 56 year sequences in the table are separated from each other by an interval of 18 years. Years in bold contained major NZ earthquakes in the year commencing January 1. Dates expressed as YYYYMMDD. Source of Raw Data: Institute of Geological & Nuclear Sciences

Table B may be further adjusted to give a 36/56 grid.

Sq 23		Sq 03		Sq 39		Sq 19
				1855 0123	+ 36	1891
		1875	+ 36	1911	+ 36	1947
1895	+ 36	1931 0202 0213	+ 36	1967	+ 36	2003 0822
1951	+ 36	1987	+ 36	2023
2007 0930 1220

NEW ZEALAND EARTHQUAKES 1840 - 2010 (mag =>6.9) IGNS
Mag	Date	Location
8.1	January 23, 1855	Wairarapa
7.8	June 17, 1929	Murchison
7.8	February 2, 1931	Hawke's Bay
7.8	July 15, 2009	Dusky Sound
7.6	March 5, 1934	Pahiatua
7.5	October 16, 1848	Marlborough
7.5	February 23, 1863	Hawke's Bay
7.5	October 19, 1868	Cape Farwell
7.3	September 1, 1888	North Canterbury
7.3	September 30, 2007	Auckland Islands
7.3	December 20, 2007	Gisborne
7.3	February 13, 1931	Hawke's Bay
7.2	June 24, 1942	Wairarapa
7.2	November 22, 2004	Puysegur Trench
7.1	March 9, 1929	Arthur's Pass
7.1	May 24, 1968	Inangahua
7.1	August 22, 2003	Fiordland
7.1	September 4, 2010	Darfield (Christchurch)
7.0	August 2, 1942	Wairarapa
7.0	February 6, 1995	East Cape
6.9	February 12, 1893	Nelson
Earthquakes in bold occurred in the 12 months beginning January 1 of those years in the Table A. Source of Raw Data: Institute of Geological & Nuclear Sciences