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dropping embers from the sky. Remains of Moa on the
South Island can be found clustered in swamps as if these
flightless birds fled en masse to avoid some catastrophe.
Similar Aboriginal legends exist in eastern Australia for a
comet event (Peck 1938 ; Flood 1995 ; Johnson 1998 ; Cahir
2002 ; Bryant et al. 2007 ). Near Wilcannia (Fig. 9.11 b),
inland in New South Wales, the Paakantji tribe also tell of
the sky falling. A great thunderous ball of fire descended
from the sky followed by a massive flood. On the north coast
of New South Wales, Aborigines speak of ''the moon setting
in the east'' and of flooding of rivers such as the Namoi from
the ocean on a clear day. A spear from the sky fell into the
sea followed by a great flood that changed the coastline. In
southeast Queensland, the Glasshouse Mountains, which lie
at the western side of the coastal plain 20 km from the ocean,
represent ancestral forms of Tibrogargan and his family who
fled a great rising of the ocean. In South Australia, Ngu-
runderi, a great ancestral figure, caused a tidal wave to
drown his two disobedient wives at Cape Jervis adjacent to
Kangaroo Island. Kangaroo Island remains enigmatic. The
island shows extensive evidence of Aboriginal occupancy;
but, when the first European—Matthew Flinders—landed on
the island in 1802, it was unoccupied. Mainland Aborigines
call Kangaroo Island, Kanga—the Island of the Dead. The
coastline also evinces signatures of cosmogenic tsunami.
Most significant are enormous whirlpools on the northern
coast of the island similar to those shown in Fig. 3.26 .On
the south coast of New South Wales, Aboriginal legends not
only recount the impact of a large comet, but also the ocean
falling from the sky (Jones and Donaldson 1989 ). At At-
cheson Rock, where evidence exists that a tsunami over-
topped this 20-25 m high headland, a dump deposit contains
numerous silcrete hand axes and shaped blades that came
from an Aboriginal camp at the head of the embayment.
Aborigines in this camp initially would have heard, but not
seen, the tsunami approaching. Their first indication of
disaster would have been when they looked up and saw the
ocean dropping down on them from the sky as the tsunami
wave surged over the headland.
From Chaps. 3 and 4 , four signatures, sourced along the
south coast of New South Wales, stand out as unique fea-
tures of mega-tsunami that can be generated by cosmic
events: chevrons (Fig. 3.10 ), imbricated boulders fronting
or overriding cliffs (Fig. 3.15 ), whirlpools bored into bed-
rock (Fig. 3.26 ), and bedrock fluting producing keel- or
cockscomb-like features (Fig. 3.24 ). Additional evidence of
these features comes from the southwest coast of Stewart
Island, New Zealand, where whirlpools and giant flutes
have been eroded into granite (Bryant et al. 2007 ). The
flutes at the southern end of Mason Bay where the tsunami
wave theoretically had a height of 60 m, rise to a height of
20 m and clearly indicate that the headland was overtopped
(Fig. 9.12 ). The orientation of the flutes point directly to the
Mahuika impact site. At Jervis Bay, on the south coast of
New South Wales, angular boulders 6-7 m in diameter have
been imbricated and stacked up to 30 m above sea level into
a protected gulch cut into the cliffs (Fig. 9.13 ) (Bryant et al.
1997 ). The boulders are not due to cliff collapse because
they rise to the top of the cliffs and there is no evacuation
zone upslope. Imbricated blocks of similar size choke the
entrances of two narrow and deep gulches at Mermaids Inlet
(Fig. 9.14 ). Finally, in the same area, at Crocodile Head,
cliff-top dunes containing angular gravel have a relief of 6.
0-7.5 m and are spaced 160 m apart. They are akin to the
undulatory to linguoidal giant ripples that are features of
catastrophic flow similar to that observed in the Scablands
of Washington State. The flow over the dunes at Crocodile
Head is theorized to have been 7.5-12.0 m deep and to have
obtained velocities of 6.9-8.1 m s -1 . The direction of the
tsunami producing this mega-ripple field came from the
South Tasman Sea. The run-ups described here, match those
of the largest historical tsunami reported in Chap. 2 .
It is possible to constrain the age of a regional cosmo-
genic mega-tsunami event using six independent lines of
evidence. First, sightings of meteorites and comets over the
last 2000 years show that the most active period happened
between 1401 and 1480 (Fig. 9.3 ). Second, 29 radiocarbon
dates have been obtained from marine shell found along the
New South Wales coast in disturbed Aboriginal middens,
deposited in tsunami dump deposits and sand layers, and
protected beneath boulders transported by tsunami (Young
and Bryant 1992 ; Young et al. 1993 , 1997 ; Bryant et al.
2007 ). Of these, three samples were obtained from Lord
Howe Island situated in the Tasman Sea halfway between
Australia and New Zealand (Fig. 9.11 ). Each radiocarbon
date can be plotted as a frequency distribution over a span of
radiocarbon years. These distributions were then converted
to calendar ones using detailed calibration tables (Stuiver
et al. 1998 ). These calendar distributions were then summed
over time to give the continuous distribution shown in
Fig. 9.3 . The results are affected by age reversals in the
calibration procedure. For example, the gap around 1380 is
just that, a gap. No shell living at that time can be dated to
that year. The most prominent peak in this chronology
centers on 1500 ± 85. There is a 95 % probability of an
event between 1200 and 1730. Third, there are dates from
disparate regions supporting a large regional tsunami event
during this time span. A pipi shell (Paphies australis)
located about 500 m inland and 30 m above sea level at
Mason Bay close to the Mahuika impact site returned an age
of 1301 ± 36 (Bryant et al. 2007 ). A massive tsunami dump
deposit of gravel, cobble, sand and shell, rising to a height of
14.3 m above present sea level and extending up to 300 m
inland on the eastern side of Great Barrier Island, New
Zealand (Fig. 9.11 c), dated between 1400 and 1700 (Nichol
et al. 2003 ). Another tsunami deposit lying 7-8 m above sea
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