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Waitangi West wa Point
CHATHAM ISLAND
(Rekohu: Wharekauri)
NEW
-35°S
-40°S
South
-45°9 /
0
Stewai t I.
1 \
ZEALAND
_5 h -p \ ) / I
Island^ j w
170°E
500 k n
Chatham
180°
Islands
176° 30' W
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
10 km
Tarawhenua Point
PITT ISLAND
(Rangiauria)
43° 45' S
44° S
Motutapu Point
SOUTH EAST1.
(Rangitira)
FIGURE 1.—Map of the Chatham Islands, showing their location relative to New Zealand (inset), and the positions
of the 21 numbered sites from which radiocarbon dates (see "Appendix") were obtained.
cle. The older soils often exhibit quite complex soil profiles, indicative
of lengthy stable periods. Such soils typically grade
from a dark-stained, indurated erosion surface at the top, underlain
by a grey-colored, strongly leached horizon, through
variably consolidated, pale- to chocolate-brown sand, often
markedly orange-stained through the formation of an incipient
iron pan, and all underlain by unconsolidated, unstained sand at
the base (see Wright, 1959; McFadgen, 1994). It seems likely
that coastal forest vegetation clothed the slopes and ridges of
these developing dunes for much of this period (especially dur­
ing the stable, soil forming phases), whereas swamps and
ephemeral brackish-water lakes filled interdune hollows, especially
in low-lying areas behind the active foredunes. It was
this mosaic of coastal forest, scrub, and swampland that provided
habitat suitable for the various land birds, waterfowl,
breeding seabirds, and land snails whose remains are now preserved
within the sands. The abundant fossil bones are found in
the sands and soils, often in situ as complete associated skeletons
in (or recently eroded from) buried soil sequences on the
flanks of hillocks or in lag deposits on the floors of the often