Geology of New Zealand Field Trip Guidebook - ResearchGate

strong beaks they can do considerable damage. For example, they will strip all the trim and
rubber off a car! They are also attracted to shiny objects like watches, glasses and jewelry.
The New Zealand Department of Conservation website claims that most Kea are good birds,
and the majority of damage is caused by a few “problem birds.” They have a banding
program to identify and help deal with these miscreants! They also note that problems with
Kea are greatly increased in areas where humans feed the birds. Please refrain from doing
so! Also, many birds are accustomed to people and quite bold. While this may seem like an
ideal opportunity for some up-close and personal with the wildlife—Beware! You find
yourself in a wrestling match over your camera, watch or necklace with a set of sharp claws
and powerful beak. My money’s on the kea.
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Day 7—Thursday 20 November. We’ll begin the day with a short walk up to some
spectacular waterfalls above the village of Arthur’s Pass. This will give you another look at
the high elevation, wet beech forest. Mostly it’s just picturesque and a chance to get the
blood moving before another big day of travel.
As we leave Arthur’s Pass on the bus, watch for glacial landforms, such as U-shaped
valleys, hanging valleys, moraines, etc. Also note the nature of some of the large streams—
braided channels choked with sediment. This is the stuff of which the coastal plain near
Christchurch is built.
Stop 1: Kura Tawhiti Conservation Area—Castle Hill
We will do a short hike here to look at some rocks that are very different from the dark
colored, laminated Torlesse rocks visible in most of the hills. The rocks we see here are in a
down-faulted inlier of younger Cretaceous to Tertiary rocks. As you look around, consider
not only what you can see underfoot, but also the surrounding hills.
Notebook Assignment: What kind of rock is this? The outcrops here have very different
“shapes” to what we have seen elsewhere. Why? This rock is younger than the Torlesse
rocks. Compare the amount and character of deformation of these rocks to that in the
Torlesse group. What is going on?
Given the striking nature of the landscape here, it is not surprising that it is also an important
Maori cultural site associated with Maori myths and rock art. The spot was an important
stopover on the greenstone trade routes to the West coast and today has protection as an
important Maori cultural site. Visitors are asked to stay off the rocks in respect for the site’s
cultural significance.
Stop 2: Torlesse Range Pullout
The rocks exposed here are near the type section of the Torlesse Supergroup [Sugate, 1961
#11], a kilometers thick pile of interbedded greywackes (sandstones with rock fragments and
a clay rich matrix) and shales that range in age from late Paleozoic through Mesozoic.
Rocks like these outcrop over about a quarter of the South Island in an elongate belt along the
Southern Alps. To the east they are unconformably overlain by later deposits. To the west
they grade into the Haast Schist, a metamorphosed equivalent. Torlesse rocks are notoriously
difficult to work with—they are of unknown age but huge thickness, contain few distinctive
lithologies or marker beds, are rarely fossiliferous and are strongly deformed. In this area,
Torlesse rocks are mapped as Triassic and Jurassic (Suggate 1978) in age (early to middle
Mesozoic). The rock types we see here are typical of Torlesse, but elsewhere these
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