54
TE
AROHA
EARTHQUAKE, 9 JANUARY
R. D. A d a m s ,
M. G . Muir and R. J . K e a n * '
d e t e r m i n e d f r o m r e a d i n g s at 1 5 s t a t i o n s
N e w Z e a l a n d s e i s m o g r a p h n e t w o r k is :-
ABSTRACT
T h e T e A r o h a e a r t h q u a k e of 9 J a n u a r y
1 9 7 2 { N. Z. S. T . ) w a s of o n l y m o d e r a t e m a g n i t u d e
( 5 . 1).
It o c c u r r e d at a s h a l l o w d e p t h w i t h i n
a f e w k i l o m e t re s of T e A r o h a , w h e r e an
i n t e n s i t y of MM V I I w a s r e a c h e d .
Damage was
m a i n l y c o n f i n e d to d o m e s t i c c h i m n e y s a n d c o n t e n t s of b u i l d i n g s in the Te A r o h a r e g i o n , but
the felt a r e a ex t e n d e d a s f a r as A u c k l a n d ,
Mangakino and Whakatane.
Numerous after shocks
o c c u r r e d in t h e f o l l o w i n g m o n t h .
A n e a r t h q u a k e w a s f e l t e x t e n s i v e l y in the
W a i k a t o a n d s u r r o u n d i n g r e g i o n s at 9 • 3 3
a.m.
( N . Z . S . T . ) on S u n d a y , 9 t h J a n u a r y 1 9 7 2 .
Its
c e n t r e w a s w i t h i n a f e w k i l o m e t r e s of T e A r o h a ,
a t o w n of s o m e 3 > 5 0 0 i n h a b i tant s, w h e r e a s u b s t a n t i a l a m o u n t of m i n o r d a m a g e
occurred.
T h e m a i n e a r t h q u a k e h a d a m a g n i t u d e of
5 . 1 ,
a n d w a s f o l 1 o w e d t h r e e m i n u t e s l a t e r by
a n o t h e r s h o c k of m a g n i t u d e
6.
About 1 6 0
a f t e r s h o c k s o f m a g n i t u d e 2 . 5 or g r e a t e r w e r e
r e c o r d e d in the f i r s t m o n t h f o i l o w i n g t h e
earthquake.
S h o c k s of t h e s i z e of t h e m a i n
e v e n t a r e r e l a t i v e l y c o m m o n in N e w Z e a l a n d ,
where about 1 0 shallow events a y e a r have a
m a g n i t u d e of 5 o r g r e a t e r .
T e A r o h a l i e s a b o u t 1 0 0 km s o u t h - e a s t of
A u c k l a n d n e a r t h e n o r t h - w e s t e r n l i m i t o f the
M a i n S e i s m i c R e g i o n of N e w Z e a l a n d ( E i b y , 1 9 7 1 )
a n d is p e r i o d i c a l l y s u b j e c t e d to s h a k i n g f r o m
e a r t h q u a k e s o r i g i n a t i n g in t h i s r e g i o n .
The
o n l y o t h e r e a r t h q u a k e in r e c e n t y e a r s that h a s
b e e n l o c a t e d c l o s e to Te A r o h a is t h a t of 3 0
J u l y 196^,
of m a g n i t u d e 4 , 0 , at a p o s i t i o n
t h a t a g r e e s w i t h that of t h e 1 9 7 2 s h o c k w i t h i n
t h e l i m i t s of e r r o r .
T h i s e a r t h q u a k e is
r e p u t e d to h a v e d a m a g e d c h i m n e y s in T e A r o h a ,
a n d w a s f e l t at i n t e n s i t y M M IV a s f a r a f i e l d
as W a i h i , K a t i k a t i and T a u r a n g a .
T e A r o h a i s s i t u a t e d on t h e f a u l t - c o n t r o l l e d
scarp w h e r e the Recent a l l u v i u m of the H a u r a k i
P l a i n s m e e t s t h e n o r t h e r n p a r t of t h e K a i m a i
R a n g e s , w h i c h h e r e s t r i k e in a N N W - S S E
direction.
T h e r a n g e s are c o m p o s e d of T e r t i a r y
v o l c a n i c r o c k , a n d t h e a n d e s i t e c o n e of M t .
T e A r o h a r i s e s t o 9 5 0 m w i t h i n 3 km of the
town.
T h e W a i h o u River, r u n s a l o n g t h e b a s e of
t h e r a n g e s.
SHOCK
The
*
formal
1972
Jan
9
(Jan
8
origin
of
the
main
d
d
09
2 l
3 3
h
Focal
(from
error
3 1
km
of
phases
Local
00 .1±0 '5
S
S
the
N.Z.S.T.
S
00 .1
of
U.T.)
175°.69^0°.05E
12
depth:
Standard
m
33™
h
37°.58±0°.03S,
Richter
INTRODUCTION
MAIN
1972
(assumed)
origin:
at
15
Magnitude
2
s
. 6
stations)
(M ):
L
5*1
D e t a i l s of s t a t i o n r e a d i n g s w i l l b e
p u b l i s h e d in the N e w Z e a l a n d
Seismological
R e p o r t for 1 9 7 2 .
T h e e p i c e n t r e is k km to t h e s o u t h of
Te A r o h a , and 1 km to t h e e a s t of W a i h o u .
Its
f o r m a l s t a n d a r d e r r o r i s a b o u t k km, a n d the
e p i c e n t r e m u s t n o t be c o n s i d e r e d to be l o c a t e d
more a c c u r a t e l y than this.
The epicentre falls
m i d - w a y be t w e e n t h e c o n c e a l e d f a u l t i n g pre s u m e d
to l i e a l o n g t h e b a s e of the h i l l s , a n d t h e
l a t e Q u a t e r n a r y t r a c e t h a t is m a p p e d r o u g h l y
p a r a l l e l to the m a i n r a n g e s , a b o u t 8 km to
thei r s o u t h - w e s t , n e a r t h e t o w n of W a i t o a
(Healy, Schofield and Thompson,
196^).
No
m o v e m e n t w a s o b s e r v e d on e i t h e r of t h e s e
faults.
T h e f o c a l d e p t h of 1 2 km h a s b e e n
a r b i t r a r i l y a s s i g n e d , as the c l o s e s t s e i s m o g r a p h s t a t i o n , K a r a p i r o , at a d i s t a n c e of
k1
km, w a s t o o d i s t a n t to e n a b l e t h e d e t e r m i n a t i o n
of a r e l i a b l e d e p t h s h a l l o w e r t h a n t h i s .
S t r o n g a r r i v a l s of the p h a s e P g at m a n y
sei s m o g r a p h stat i o n s s h o w
—
that the
f o c u s c o u l d not h a v e b e e n s i g n i f i c a n t l y d e e p e r
t h a n 1 2 km.
On the o t h e r h a n d , t h e c o m p a r a t i v e ly h i g h i n t e n s i t y r e p o r t e d at T e A r o h a ,
f r o m an e a r t h q u a k e of o n l y m o d e r a t e m a g n i t u d e ,
s u g g e s t s t h a t the f o c u s c o u l d w e l l b e
appre ciably shallower.
T h e d i r e c t i o n s of f i r s t m o t i o n of t h e
P - w a v e a r r i v a l c o u l d be r e a d at o n l y six of the
s t a t i o n s recording the e a r t h q u a k e .
These
o b s e r v a t i o n s w e r e not n u m e r o u s e n o u g h to d e f i n e
a source mechanism closely, but were consistent
w i t h normal faulting with nodal p l a n e s s t r i k i n g
a p p r o x i m a t e l y N - S , o n e d i p p i n g s t e e p l y to t h e
w e s t a n d the o t h e r s h a l l o w l y t o the e a s t .
The
m o s t 1 i k e l y m e c h a n i s m a p p e a r s t o be a d o w n w a r d
m o v e m e n t of t h e p l a i n s r e l a t i v e to t h e r a n g e s ,
along a steeply dipping normal fault.
shock
Seismological Observatory, Geophysics
D i v i s i o n , D e p a r t m e n t of S c i e n t i f i c a n d
Indus trial R e s e a r c h , W e l l i n g t o n .
Bulletin of N.Z. Society for Earthquake Engineering, Vol. 5, No.2 June 1972.
FELT
EFFECTS
Fig.
selection
1 s h o w s an i s o s e i s m a l m a p a n d a
of t h e o b s e r v a t i o n s o f i n t e n s i t y
on
Felt observations and isoseismals for Te Aroha earthquake.
Innermost isoseismal is MM V I I .
Intensities are on Modified Mercalli Scale.
56
FIGURE
2
Broken c h i m n e y on a h o u s e n e a r t h e h i i l in T e A r o h a .
Camera pointing towards east.
57
w h i c h it is b a s e d .
These o b s e r v a t i o n s are
t h o s e r e p o r t e d by the S e i s m o l o g i c a l O b s e r v a tory •s r e g u l a r n e t w o r k of felt r e p o r t e r s,
s u p p l e m e n t e d by the di s t r i b u t i on of a d d i t i o n a l
questionnaires.
O n e of us ( R . D . A . ) v i s i t e d
the a r e a f r o m 1 1 to 1 3 J a n u a r y .
It is e v i d e n t f r o m F i g . 1 that t h e h i g h e s t
i n t e n s i t i e s w e r e c o n f i n e d to t h e e p i c e n t ral
area.
MM V I I w a s r e p o r t e d f r o m T e A r o h a ,
W a i h o u (k km to the s o u t h - w e s t ) , Te A r o h a
W e s t ( 5 km to t h e s o u t h - e a s t ) a n d E l s t o w (7 km
to the n o r t h - w e s t ) .
O n e r e p o r t f rom W a i h o u
w a s a s s i g n e d an i n t e n s i t y of M M V I I I .
In T e A r o h a i t s e l f t h e r e w a s a p r o n o u n c e d
d i f f e r e n c e in t he d e g r e e of d a m a g e b e t w e e n the
e a s t e r n par t of t h e t o w n on the 1 o w e r si ope s
of t h e h i l l , and the we s t e r n p a r t of t h e
a l l u v i a l p l a i n a c r o s s the W a i h o u R i v e r ,
a p p a r e n t l y d u e to the d i f f e r e n c e in the type
of u n d e r l y i n g r o c k in the two are a s.
In the
s h o p p i n g a r e a of W h i t a k e r S t r e e t a l o n g the
b o t t o m of t h e h i l l , g o o d s on s h e 1 v e s a n d in
d i s p l a y s we re n o t b a d l y a f f e c t e d , a n d no g r o s s
d a m a g e w a s e v i d e n t , a l t h o u g h t h e r e w a s some
chimney damage.
(Fig. 2 shows a broken
c h i m n e y on a hou se s i t u a t e d at t h e b a s e of the
hill,)
In t h i s a r e a the i n t e n s i t y w o u l d be
a b o u t MM V I .
A e r o s s the riv er on the a l l u v i u m ,
smal 1 shops s u f f e r e d substantial stock losses,
a n d a l o n g S t a n l e y S t r e e t a l a r g e p r o p o r t i o n of
c h i m n e y s w a s d a m a g e d , i n c l u d i n g tho se of
m o d e r n w e l l - b u i l t h o u se s.
Here there were
a l s o m a n y r e p o r t s of h e a v y f u r n i t u r e b e i n g
m o v e d and t e l e v i s i o n sets being o v e r t u r n e d .
S u c h o b j e c t s w e r e t h r o w n in a we st e r l y d i r e c t i o n ,
a w a y from the h i l l .
In thi s a r e a t h e i n t e n s i t y
w a s g e n e r a l l y a s s e s s e d at MM V I I .
There were
n o r e p o r t s of d a m a g e to u n d e r g r o u n d
services
i n T e A r o h a , a n d o n l y a f e w i n s t a n c e s of
broken lavatory pans.
No c h a n g e s w e r e r e p o r t e d
i n the f l o w of t h e h o t s o d a s p r i n g s in t h e Te
Aroha Domain.
A f e w k i l o m e t r e s to the s o u t h of T e A r o h a ,
t h e g r a n d s t a n d of t h e Te A r o h a J o c k e y C l u b
s u f f e r e d the c o l l a p s e of i n t e r n a l p a r t i t i o n s
a n d n e a r b y t h e r e w a s m u c h d a m a g e to m o n u m e n t s
in the Te Aroha C e m e t e r y (Fig. 3 ) . As with
t h e f u r n i t u r e in Te A r o h a , in a l m o s t a l 1
i n s t a n c e s the d i r e c t i o n of f a l l w a s to the
w e s t , a w a y f r o m t h e hi 1 1 .
T h e M M V I i s o s e i s m a l i n c l u d e s W a i t o a ( 8 km
t o the s o u t h - w e st of T e A r o h a ) a n d W a i h i .
The
i n t e n s i t y h a d in g e n e r a l f a i l e d to M M V at
M o r r i n s v i l l e , but some m i n o r c h i m n e y d a m a g e
would indicate MM V I .
The MM V i s o s e i s m a l
e x t e n d s to H a m i l t o n a n d i n c l u d e s M a t a m a t a ,
T a u r a n g a , a n d t h e s o u t h e r n h a l f of t h e
Coromandel Peninsula.
T h e l i m i t s of t h e f e l t
a r e a s e x t e n d to A u c k l a n d , M a n g a k i n o , R o t o r u a
and Whakatane.
O n e i n s t a n c e of d a m a g e at s o m e di s t a n c e
f r o m T e A r o h a w a s t h e e f f e c t on a ^ 0 m h i g h
b r i c k c h i m n e y at a d a i r y f a c t o r y at H a u t a p u ,
n e a r C a m b r i d g e , kO km to the s o u t h - w e s t of Te
A r o h a in a n a r e a o f g e n e r a l i n t e n s i t y M M V .
S o m e s m a l 1 v e r t i c a l c r a c k s we re p r e sent in the
c h i m n e y before the e a r t h q u a k e , but these
o p e n e d to be c o m e m u c h m o r e e v i d e n t a f t e r the
shock.
On the e a s t e r n s i d e , c r a c k s w e r e
v i s i b l e m o s t of t h e w a y d o w n t h e c h i m n e y , in
p i a c e s u p to \ cm w i d e .
A
landslide
o-ccurring
on
the
reported
shore
in
the
of L a k e
p r e ss
as
Karapiro,
12
km
u p s t r e a m f r o m the d a m , and kO km f r o m T e
Te A r o h a , w a s f o u n d to be o n l y a f e w f e e t
a c r o s s a n d to ha ve o c c u r r e d a b o u t an h o u r
a f t e r t he e a r t h q u a k e .
T h e E a r t h q u a k e and W a r D a m a g e C o m m i s s i o n
h a s r e c e i v e d a b o u t 1 3 0 0 c l a i m s a r i s i n g f r o m the
e a r t h q u a k e , m a i n l y f r o m Te A r o h a a n d i t s
immediate surroundings.
The total amount paid
out in c l a i m s is e st i m a t e d at a b o u t $ 1 6 0 , 0 0 0 .
A p a r t f r o m a f e w c l a i m s f o r d a m a g e to l a r g e r
s t r u e t u r e s s u c h as t h e g r a n d s t a n d a n d f a c t o r y
c h i m n e y m e n t i o n e d a b o v e , the c l a i m s a r o s e
m a i n l y f r o m d a m a g e to d o m e st i c c h i m n e y s a n d
c o n t e n t s of b u i l d i n g s .
AFTERSHOCKS
T h e 1 a r g e st aft er s h o c k o c c u r r e d o n l y t h r e e
m i n u t e s a f t e r the m a i n s h o c k , a n d w a s the f i r s t
a f t er s h o c k that c o u l d be i d e n t i f i e d .
Its
m a g n i t u d e w a s ^. 6 , a n d it s r e l a t i o n to t h e m a i n
s h o c k is s u c h t h a t the two e v e n t s c o u l d b e
c o n s i d e r e d as a d o u b l e e a r t h q u a k e •
The next
l a r g e s t s h o c k of t h e s e q u e n c e o c c u r r e d on
J a n u a r y 1 8 at 0 7
25
( N . Z . S . T . ) , and had a
m a g n i t u d e of k. I.
T h i s m a g n i t u d e i s c l o s e r to
that u s u a l l y f o u n d f o r t he l a r g e st a f t e r s h o c k
f o l l o w i n g an e a r t h q u a k e of m a g n i t u d e 5 • 1 •
n
m
A p r e l i m i n a r y a n a l y sis of a f t e r s h o c k s
d u r i n g the f i r s t 3 3 d a y s , u p to 1 9 7 2 F e b r u a r y
1 0 , h a s be en c a r r i e d o u t , a n d 2 1 3 h a v e b e e n
a s s i g n e d p r o v i s i onal m a g n i t u d e s, w h o s e
di s t r i b u t i o n is g i v e n in T a b l e I .
It is
l i k e l y t h a t all e v e n t s d o w n to m a g n i t u d e 2 . 5
h a v e b e e n r e c o g n i s e d , b u t t h e f a l l - o f f in
n u m b e r s b e l o w t h i s m a g n i t u d e is p r o b a b l y d u e
to i n c o m p l e te d e t e c t i o n .
T a b l e 2 is a c h r o n o l o g i c a l l i s t of the
s h o c k s of m a g n i t u d e 3 • 5 a n d g r e a t e r .
T h i s is
b a s e d on a p r o v i s i o n a l d e t e r m i n a t i o n of
m a g n i t u d e s only, and f u r t h e r studies c o u l d
c a u s e t h i s l i s t to b e a m e n d e d .
The initial
a c t i v i t y on J a n u a r y 9 w a s f o i l o w e d by a s i n g l e
s h o c k on J a n u a r y 1 1 , a n d t h e n f o u r sho cks on
J a n u a r y 1 2 and 13.
There was another period
of a c t i v i t y f r o m J a n u a r y l 6 to 19s
after which
t h e n u m b e r of s h o c k s of a l 1 m a g n i t u d e s
d i m i ni s h e d g r e a t l y .
T w o i s o l a t e d s h o c k s of
m a g n i t u d e s 3 • 7 a n d 3 • ^ on F e b r u a r y 6 a n d 7
w e r e not a c c o m p a n i e d by a n y i n c r e a s e in t h e
n u m b e r of s m a l l e r s h o c k s .
T h e p o s i t i o n s of t h e a f t e r s h o c k s d o n o t
a p p e a r to d i f f e r g r e a t l y f r o m t h a t of t h e
main shock.
A n i n d i c a t i o n of s c a t t e r m a y be
o b t a i n e d f r o m d i f f e r e n c e s in t h e i n t e r v a l
b e t w e e n t h e P a n d S p h a se s re c o r d e d at
K a r a p i r o , the" n e a r e s t s e i s m o g r a p h s t a t i o n ,
w h i ch is at a di s t a n c e of kl km f r o m the
e p i c e n t r e a d o p t e d f o r the m a i n s h o c k .
For this
d i s t a n c e the time i n t e r v a l b e t w e e n P and S wave
a r r i v a l s f r o m a f o c u s at a d e p t h of"~12 k m " i s
5.0s.
A n S - P i n t e r v a l of 5 . 0 s w a s , in f a c t ,
m e a s u r e d f o r 9 3 of the 2 0 ^ e v e n t s of t h e
s e q u e n c e f or w h i c h thi s c o u l d be m e a s u r e d .
9^$
of a l l e v e n t s h a d S-P i n t e r v a l s in t h e r a n g e of
k.5 to 5 . 5 s , a n d a l l m e a s u r e d i n t e r v a l s w e r e
w i t h i n t h e 1 i m i t s of ~k. 0 a n d 6 . 0 s .
T h e se
r a n g e s i m p l y t h a t the e x t r e m e v a r i a t i o n in
di s t a n c e of a f t e r s h o c k s f r o m K a r a p i r o i s 8 km
in e i t h e r d i r e c t i o n , a n d that 9k% of r e c o r d e d
e v e n t s w e r e at a di s t a n c e w i t h i n k km of t h a t
of the m a i n s h o c k .
B e c a u s e of o v e r 1 o a d i n g of
the i n s t r u m e n t s, the S-P i n t e r v a l at K a r a p i r o
c o u l d n o t be r e a d f o r the l a r g e s t a f t e r s h o c k s ,
which w i l 1 be located i n d e p e n d e n t l y .
It w o u l d
58
far
New
seem, h o w e v e r, t h a t t he s m a l l e r a f t e r s h o c k s
w e r e c o n c e n t r a t e d in an a r e a w i t h i n a f e w
k i l o m e t r e s of t h e m a i n s h o c k .
REFERENCES
E i b y , G.
Zealand.
5.0
to
to
k.
A. 1 9 7 1 : S e i s m i c R e g i o n s
Roy. Soc, N . Z . B u l l . 9 :
1
Earthquake
Sequence,
MAGNITUDE-FREQUENCY
1972.
RELATIONSHIP
Range
Number
of
5 . *
l
1*.9
1
to
k.k
3 . 5
to
3.9
15
3.0
to
2.5
to
2.9
101
2.0
to
0
(main
event)
50
k
TABLE
PRELIMINARY
Aroha
LIST
Date s and times
Subtract
Jan
Event s
1
Te
are
I 2
n
Sequence,
MAGNITUDE
1972.
3 . 5
AND
GREATER
g i v e n in N e w Z e a l a n d S t a n d a r d
to o b t a i n U n i v e r s a l T i m e .
M
d
h
m
s
09
09
33
00.
09
36
20.^
k.6
09
58
06.9
3 . 5
10
37
5 2 . 6
3 . 8
12
36
1 6 . 6
3 . 6
16
5k
20.
^
3.8
1 1
03
38
03.
2
12
05
33
3 1 . 9
16
kk
3 3 . ^
3 . 7
1
OF
5
2
Earthquake
OF S H O C K S
L
Time.
h
m
0^
00
08
6
3 . 8
05
12
10
2
3 . 8
12
k6
11
7
3 . 5
20
59
59
3
3 . 7
17
19
02
3 ^ . 5
3 . 5
18
00
06
^5.
3.6
07
25
U9. 9
k.
3.6
19
22
30
kl.
1
3 . 6
06
00
00
23.
2
3 . 7
5.
d
1
of N e w
153-60.
H e a l y , J., S c h o f i e l d , J. G., T h o m p s o n , B . N . ,
196^:
Sheet 5 , R o t o r u a ( 1 s t Ed.) " G e o l o g i c a l
M a p of N e w Z e a l a n d " , 1 :
250,000.
TABLE
Magnitude
buildings
in
W e t h a n k M r . J. L. G i l 1 , S e c r e t a r y ,
E a r t h q u a k e and War D a m a g e Commi s sion, for
i n f o r m a t i o n on the e x t e n t and c o s t of d a m a g e ;
M r . C. A. Thorn of P i a k o C o u n t y C o u n c i l f o r
a d v i c e a n d h e l p in c o l l e c t i n g f i e l d i n f o r m a t i o n ,
a n d M i s s D. E . W a r e f o r as si s t a n c e in
c o m p u t i n g ; M i s s F i o n a A d a m s h e l p e d in t a k i n g
n o t e s d u r i n g f i e l d s t u d i e s.
T h i s e a r t h q u a k e is a f u r t h e r r e m i n d e r t h a t
e a r t h q u a k e s of m o d e r a t e m a g n i t u d e c a n c a u s e
s i g n i f i c a n t d a m a g e w h e n t h e y o c c u r at s h a l l o w
depths beneath populated areas.
The intensit y
of M M V I I r e p o r t e d in the e p i c e n t r a l r e g i o n
is a b o u t a s g r e a t a s c o u I d be e x p e c t e d f r o m a n
e a r t h q u a k e of thi s m a g n i t u d e u n d e r n o r m a l
condi tions.
T h e d a m a g e r e p o r t e d f r o m Te A r o h a
s h o w s a g a i n t h a t d o m e s t i c c h i m n e y s r e m a i n by
PRELIMINARY
of
ACKNOWLEDGEMENTS
CONCLUSIONS
Aroha
feature
F u r t h e r d e t a i l e d w o r k is b e i n g u n d e r t a k e n
on t h e s e i s m o l o g i c a l a s p e c t s of t h e a f t e r s h o c k
sequence, w h i c h has been well recorded.
A l t h o u g h the a f t e r s h o c k s a p p e a r to o r i g i n ate f r o m a s m a l l v o l u m e , t h e i r m e o n a n i s m s a r e
not a l l ide nt i c a l .
At K a r a p i r o the r a t i o of
r e c o r d e d a m p l i t u d e of S w a v e s r e 1 a t ive to P
w a v e s v a r i e d by m o r e t h a n an o r d e r of m a g n i t u d e ,
and a l t h o u g h t h e dire c t i o n of i n i t i a l m o t i o n of
the P w a v e w a s u s u a l l y c o m p r e s s i o n a l j in some
case's d e f i n i t e d i l a t a t i o n a l f i r s t m o t i o n s w e r e
recorded.
T h u s the a f t e r s h o c k s c a n n o t a l 1 be
r e g a r d e d as s i m p l y r e p e a t i n g the me c h a n i sm
i n v o l v e d in t h e m a i n e a r t h q u a k e .
Te
the m o s t v u l n e r a b l e
Zealand.
Jan
13
16
Feb
s
M
1
L
3 . 6
1