School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Natural Landscapes · Tongariro National Park
Mt Ngauruhoe 2291m
Mt Ruapehu 2797m
Mt Tongariro 1967m
Jacek Drecki
School of Geography & Environmental Science · The University of Auckland · Private Bag 92019 · Auckland · New Zealand
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
© SGES, The University of Auckland, 2003
Structure
Introduction
Landscape Origins
• Volcanism
– Volcanic Landscape
•
Erosion – Deposition System
– Erosion – Deposition
•
•
•
•
Glaciation
Tectonism
Vegetation
Human Impact
Summary
Recommended Literature
Acknowledgements
Emerald Lakes
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
1
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Introduction
•
Tongariro National Park (TNP) encompasses a group of volcanoes in
the centre of the North Island
•
Mt Ruapehu is the North Island’s highest mountain 2797m
•
It is the oldest National Park in New Zealand
•
TNP is a World Heritage Area
•
Landscape of TNP attracts many people from all over the world
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
2
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Tongariro National Park – World Heritage Area
•
In 1990 UNESCO declared TNP as a World Heritage Area for its natural
landscape features
•
Additionally in 1993 it became the first site in the world to receive
Associative Cultural Landscape status for the strong cultural and spiritual
associations the mountains of the Park have for local Maori tribes
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
3
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
The following landscape features are the most recognised tourist
attractions of TNP:
•
Mt Ruapehu and its Crater Lake
•
volcanic cone of Mt Ngauruhoe
•
craters along Tongariro Crossing track
•
constant volcanic
and hydrothermal
activity
•
permanent snow
and ice
Whakapapa Visitor Centre, DoC
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
4
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Location of Tongariro National Park
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
5
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Tongariro National Park is an excellent place to study natural
landscapes:
•
a dramatic landscape with well developed landforms
•
relatively simple origin – a group of volcanic cones
•
a continuous process of landscape making
•
some elements of the landscape are developed in a very typical way and are
excellent examples of a particular form or process
•
unrestricted, easy access to the Park
•
important landmark of New Zealand,
widely recognised around the world
•
a landmark of cultural and
spiritual importance for the local
people, Maori in particular
Mt Ruapehu from State Highway 48
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
6
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Landscape Origins
Three major factors are continuously shaping the TNP landscape:
•
volcanism – its mountain building ability
•
erosion – controlled mainly by climate and gravity, such as action of water,
wind or glaciers
•
deposition – builds the ring plain around the volcanoes
Other important factors:
•
glaciation in the past
(“Ice Age”)
•
tectonic faulting
•
vegetation zonation
•
human impact
Reflection of Mt Ruapehu in Lake Rotokura
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
7
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Landscape Origins: Volcanic Landscape
Volcanism is a result of Earth crust movement and it can:
•
build up mountains (like those in TNP)
•
create depressions like calderas, craters and pits, which can fill with water
and make lakes
•
scatter or bury the land with volcanic deposits like tephra, ignimbrites or
lahars
•
destroy or change vegetation patterns
•
act violently and unpredictably
Steam eruption from Mt Ruapehu seen from Taurewa (SH 47)
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
8
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Volcanic mountain building ability is
well represented by recent eruptions
of Mt Ruapehu and Mt Ngauruhoe
Mt Ngauruhoe eruption in 1975
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
9
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Volcanoes in Tongariro National Park
are relatively young (around
260 000 years old) and constitute the
Tongariro Volcanic Centre. They form
the southern most part of the Taupo
Volcanic Zone.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
10
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Simplified diagram showing Earth crust movement resulting in
volcanism
W
Mt Taranaki
Mt Ruapehu
Volcanic deposits
E
Set of tectonic faults
Pacific Ocean
Pacific Plate
Indo-Australian Plate
Movement friction generates heat that
melts rocks into liquid magma
Hot liquid magma under pressure
escapes upwards and builds volcanoes
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
11
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Volcanic Landscape
In general the volcanic landscape of TNP consists of:
•
multiple stratovolcanoes: Mt Ruapehu, Mt Tongariro, Kakaramea-Tihia Massif
•
single cone stratovolcanoes: Hauhungatahi, Pihanga
•
parasitic vents and cones: Pukeonake, Ohakune Craters, Saddle Cone
•
explosive craters: Tama Lakes,
Lake Rotokura, Emerald Lakes
•
ring plains
•
abundant other features like lava
flows, dikes, craters, ash layers,
geothermal hot springs and
fumaroles, volcanic rocks, lahar
deposits
Mt Ngauruhoe eruption in 1975
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
12
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Key elements of the volcanic landscape of Tongariro National Park
Stratovolcano
Ash and lahar deposits
on a ring plain
Vent
Multiple stratovolcano
Crater Lake
Layers (strata) of
lava and tephra (ash)
Crater
Parasitic cone
Mantle of ash and
lahar deposits
Tectonic faults
Basement rock
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
13
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Mt Ruapehu is a typical example of a multiple stratovolcano
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
14
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Mt Tongariro is also a multiple stratovolcano. Multiple means “of many
vents and craters” therefore there are many hills, ridges and basins
separating them
North Crater
explosion pit
North
Crater
Blue Lake crater
Basin of Central
“Crater”
Red
Crater
Explosion craters of
Emerald Lakes
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
15
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Mt Ngauruhoe is the most spectacular example of a volcanic cone
Mt Ngauruhoe
Mt Ruapehu
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
16
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
On the top of Mt Ngauruhoe older (outer) and younger (inner) craters
can be observed
Younger crater rim
Part of older crater rim
Light coloured rocks are altered by hydrothermal activity
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
17
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Young lava flow in Oturere (Tongariro) erupted from the Red Crater
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
18
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Silhouette of “craggy” surface of a young lava flow from Ruapehu, with
Mt Taranaki in the distance
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
19
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Detail of young lava flow erupted from Mt Ngauruhoe
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
20
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Old lava flow on slopes of Mt Ruapehu sandwiched between lahar
and tephra deposits
Such a sequence of solid lava and unconsolidated debris is very vulnerable
to erosion
Whangaehu Valley
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
21
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Various lava flow formations on the
northern slopes of Mt Ruapehu
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
22
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Three differently angled lava formations on the north wall of Oturere
crater may be interpreted as giving evidence of three stages of
mountain building
Stage III
Stage II
Stage I
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
23
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Pukeonake is a parasitic cone
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
24
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Tama Lakes are a good example of explosion craters
Lower
Tama Lake
Upper Tama Lake
Note that the surrounding hills of the lakes are covered by material ejected from the craters
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
25
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Cold and highly mineralised waters of Emerald Lakes fill explosion
craters associated with activity of the Red Crater
Emerald Lakes
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
26
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Red Crater cone is built of red and dark brown scoria. Also visible is a
dike which acted as a channel along which magma surfaced
Dike
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
27
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Meads Wall is a fine example of an erosion resistant dike
Dike
Whakapapa
ski
resort
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
28
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Hydrothermal activity of Ketetahi Hot Springs
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
29
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Red Crater and its wall, facing upper
Emerald Lake, is also known for its
fumaroles
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
30
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Mountains of TNP are made of volcanic rocks of which the most
common is called andesite
Lines on this rock reflect the way the andesite lava flowed
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
31
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Andesite rock can be colourful
This rock has a characteristic
“bread crust” surface which
means it was still hot when
deposited
Shrinkage of the cooling surface was responsible for the cracks
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
32
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Crater Lake on the top of Mt Ruapehu is one of the most fascinating
volcanic features in the world. It is located directly over an active vent
and is partly dammed by a wall of glacier ice
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
33
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Murky grey and steaming water of the
Crater Lake is a result of:
•
collecting of rain and snow / ice melt
water into the crater
•
influx of rock debris from the slopes of
the crater
•
heating of the water by hot gases
escaping from magma underneath
•
stirring and mixing the water with lake
sediments by release of the gas bubbles
and convection
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
34
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
A simplified cross-section of Crater Lake
Pyramid Peak
Lake, slope and
tephra sediments
Ice
Gas bubbles
Lake sediments
Sulphur pond
Solidified magma – plug material
Hot magma
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
35
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Pieces of lake mud sediments coated with yellow crystals of sulphur
from the bottom of Crater Lake were ejected during the 1995 / 96
eruptions
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
36
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Water from the crater lake can be suddenly released by volcanic activity
or other causes and trigger lahar outburst and floods
These freshly rounded rocks (an old lava flow formation) are situated in the
path of lahars from Crater Lake. This footbridge on Whangaehu Stream is
one of the most frequently lahar damaged man-made structures in the TNP.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
37
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
This ice cave beside Crater Lake provides the overflow route for water in
the lake
Failure of the ice and volcanic debris dam in 1953 resulted in a discharge of
a huge volume of water into Whangaehu Stream, forming the lahar
responsible for the Tangiwai Disaster. This picture was taken a few days
after the event.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
38
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Rangipo Desert by the Desert Road is an active accumulation area of
the sediments carried by lahars and streams. This volcanic ring plain is
still building up
The area is not a ‘desert’ in the sense of being arid, but is simply a sparsly
vegetated, wind-swept area.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
39
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Thick section of lahar and tephra deposits on lower eastern slopes of Mt
Tongariro provide a good record of volcanic activity over thousands of
years
This Upper Waikato Stream section is about 40 metres thick and represents
a minimum of 50 thousand years of a volcanic activity.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
40
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Landscape Origins: Erosion - Deposition System
While volcanic activity in TNP leads mainly to building up the
mountains, the weathering-erosion-transport-deposition system
is trying to level them down
•
Weathering and erosion is a process of loosening and removing rock debris
•
Transport is a process of carrying eroded debris to a new location
•
Deposition is a process of accumulating the transported material
In Tongariro National Park the above processes can be performed by:
•
gravity
•
wind
•
ice
•
water
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
41
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Climate and gravity provides the
energy and agents of erosion and
deposition (wind, water, ice).
Volcanism provides the material
substance for these agents to work
upon.
The power of running water cuts into hard rock of lava
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
42
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Erosion – Deposition
Weathering and gravity is responsible for this recent lava cliff erosion
Whangaehu Valley
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
43
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Hills surrounding Lower Tama Lake are being subject to gully erosion
and scree fans are forming below them
gully
scree fan
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
44
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Stream erosion has cut valleys on lower slopes of Mt Ruapehu
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
45
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Wind erosion on Rangipo Desert
Fine sand (foreground) rests only in places where there is shelter from wind
behind larger stones and tussock vegetation.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
46
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Stream erosion was responsible for cutting into the crater of parasitic
cone Pukeonake
Slips on lower slopes of the mountains (foreground) are a very common
form of surface erosion in TNP affecting the mantle of ash deposited there
during eruptions
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
47
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Another kind of erosion process on slopes is solifluction, which is the
slow shifting of rock debris downhill
Solifluction is particularly efficient in cold climates where frequent
frost-thaw process occurs. It results in the characteristic lobe texture of the
slopes.
Upper slopes of Mt Tongariro taken over by the solifluction
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
48
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Fragile alpine vegetation is also carried downhill by solifluction
solifluction lobes
Western slopes of Mt Tongariro
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
49
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Landslides are another form of erosion - deposition process on the
mountain slopes
Little hills in the middle distance are made of rock debris deposited here by
a giant landslide (debris avalanche) which originated from upper, less stable
slopes of Mt Ruapehu (out of sight to the right of the photo).
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
50
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
A road cut exposes the debris avalanche deposits, which are overlaid by
tephra from later eruptions
SH48
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
51
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
It is believed the giant landslide originated from the area near the
Pinnacle Rocks and Iwikau Village where intrusion of dikes played an
important role in destabilising the slopes
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
52
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Deposition of stream sediments into a lake in a form of a delta
Lower Tama Lake
Lower Tama
Lake
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
53
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
© SGES, The University of Auckland, 2003
Clay and silt deposits of a former cold
water lake on the eastern slopes of
Mt Ruapehu
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
54
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
A basin named South Crater on Mt Tongariro is filled with volcanic
tephra and fine grained stream deposits
Note a small shallow lake which is being filled with yellow silt
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
55
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Fine deposits on the flat floor of the South Crater create a near perfect
cricket pitch!
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
56
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Extensive deposition of lahars, stream sediment and tephra makes the
landscape of the large volcanic ring plain around Mt Ruapehu and
Mt Tongariro
Gentle angled slopes of the ring plain
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
57
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Landscape Origins: Glaciation
The high altitude of Mt Ruapehu permits accumulation of snow to form
glaciers
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
58
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Glaciers can be a powerful landscape-shaping force
•
Movement of ice over rock leads to rock polishing, erosion and altering the
shape of valleys
•
Moving ice transports rock debris and can deposit it as moraines
•
Water melted from ice has its own capabilities of eroding, transporting and
depositing sediments
A glacial landscape is a landscape either formed or deeply altered by
the action of glaciers
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
59
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
The southern slopes of Mt Ruapehu with Mangaehuehu Glacier
exemplifies the current glaciation
semi-permanent snow
ice with characteristic crevasses
moraine ridge
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
60
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Summit area of Mt Ruapehu, as seen in this picture, can be regarded as
a typical glacial landscape
Summit Plateau and Tahurangi, the highest peak of Mt Ruapehu (2797m)
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
61
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
There are several glaciers on Mt Ruapehu, most of them in a stage of
recession. However one, flowing directly into the Crater Lake, appeared
to be growing prior to the 1995 / 96 eruptions.
The layers in the ice cliff mark annual accumulations. The dark bands are
dust that accumulated on the surface at the end of the summer melt
season. Larger layers of “dirt” can also mark periods of volcanic activity.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
62
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Glacially polished and grooved rock, the classical glacial erosion form
Mangaehuehu Glacier
This glacial grooves are called striations. They are formed by rocks held in the ice being scratched along
the underlying bedrock surface.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
63
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Apart from the contemporary small glaciers on Mt Ruapehu, there is
also evidence of former larger glaciers that shaped the landscape of
Tongariro National Park during the past Ice Age
terminal moraine
lateral moraine
lava flow
stream deposits
Waihohonu Valley at the foot of Mt Ngauruhoe is widely regarded as being glacially modified
and later partly filled by young Ngauruhoe lava flows and stream deposits.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
64
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
These hills enclosing Mangaturuturu Valley (SW Ruapehu) are old
glacial moraines
glacial moraine ridges
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
65
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Lower part of Mangatepopo Valley also has lateral moraine ridges
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
66
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
There are also ice moulded and
grooved (striated) lava flows outside
the extent of the current glaciers on Mt
Ruapehu. They provide us with proof
of earlier and larger glaciations. This
example is from the west side of Mt
Ruapehu.
ice flow
direction
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
67
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Landscape Origins: Tectonism
Tectonic faults are a very common feature in addition to volcanic
activities
fault
An active Rangipo fault is seen in a road cut
beside SH1 (Desert Road) and is the subject of a geology lesson for a group of students
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
68
School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Tectonic faults can create scarps in the landscape
fault scarp
Northern slopes of Mt Ruapehu
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Landscape Origins: Vegetation
Vegetation is an important element of the landscape
•
It has an important role in stabilising the slopes and preventing erosion
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It plays a role in developing fertile soil on initially barren rocky land
•
It makes the landscape more habitable for animals and people
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Vegetation patterns in TNP show close dependence on:
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altitude
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volcanic activity in conjunction with wind direction
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water supply
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exposure
Mountain beech forest
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Since the average temperature drops with height, it is understandable
that vegetation changes with altitude too
A zonation can be seen from areas of no vegetation on the summit, through
alpine flora, tussock grassland and beech forest to relatively wet podocarp
forest. Here at Ohakune the podocarp forest was changed into pastures by
man. Totara trees in the foreground are secondary growth.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Vegetation cover of TNP was devastated during the Taupo Eruption 1800
years ago. Since then it has regenerated slowly. However on the eastern
and northern sides of Mt Ruapehu the regeneration process is
particularly slow due to lahar activity and stream deposition on the
Rangipo Desert combined with volcanic ashfalls, falling most frequently
here with prevailing south-westerly winds.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Shelter and supply of water are crucial for plants therefore stream
valleys are colonised by trees first
Tawhai Falls
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Further away from volcanic activity and at lower altitudes, dense bush
covers the land making its own imprint on the landscape
Fern and rimu forest on the shores of Lake Rotopounamu - northern enclave of the TNP
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Landscape Origins: Human Impact
TNP is a protected area and human impact on the environment and
landscape is limited. However, localised man-made structures are
dominant in the landscape
Whakapapa ski resort
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Some man-made elements of the landscape can be regarded as
landmarks
The Grand Chateau - Whakapapa
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Sometimes human structures may be a symbolic addition to the
landscape
Oturere
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
An example of a human impact that spoils the aesthetics of the
landscape
Erua
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Natural Landscapes Summary
The TNP is predominantly a volcanic landscape
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It has a volcanic origin
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It has a great variety of typical volcanic forms and features
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Volcanoes are by far the largest elements of the landscape
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Volcanic activity plays the most important role in this landscape at present
•
Results of every other landscape shaping process can be easily overridden
by renewed volcanic activity (as was the case in the geological past)
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Other kinds of landscape found locally within TNP include:
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a glacial landscape
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a high mountain landscape with typical slope erosion features
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a landscape of river valleys with water erosion and deposition features
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a biological landscape with strong altitudinal zonation of plant types
Other factors like tectonism and human activity make additional
imprints on the landscape of TNP but at a relatively minor scale
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Superficial study of a landscape can pose a difficulty
This view is of a typical high mountain landscape rather than a volcanic one.
In order to recognise its volcanic origin we would have to study the rocks, or
have a wider perspective and see the outer slopes of the mountain where the
conical shape of a volcano is revealed.
Mt Ruapehu’s peaks of Mitre Peak,
Pyramid Peak, Cathedral Rocks
and Te Heuheu with Whangaehu
Valley in the foreground
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
There are elements of at least three different kinds of landscape
recognisable in this photograph. Can you identify them?
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Recommended Literature
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Esler AE, 1965, Tongariro National Park Handbook, Tongariro National Park
Board, Wellington.
•
Gregg DR, 1961, Volcanoes of Tongariro National Park, New Zealand DSIR,
Wellington.
•
Johnston D and V Neall, 1995, Ruapehu Awakens: the 1945 eruption of
Ruapehu, The Science Centre and Manawatu Museum Scientific Monograph
No 1, Palmerston North.
•
Parkmap Tongariro 273-04, 1996, Department of Conservation, Edition 5,
Wellington.
•
Soons JM and MJ Selby (eds), 1982, Landforms of New Zealand, Longman
Paul Limited.
•
Williams K, 1989, Volcanoes of the south wind, Tongariro Natural History
Society, Wellington.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
Acknowledgements
The Natural Landscape resource material has been prepared by Jacek Drecki
MSc for the School of Geography and Environmental Science, The University
of Auckland.
The author wishes to thank Professor Paul Williams for his input and
valuable comments with regards to the scientific content of this material and
express his appreciation to Marie McEntee for her careful proof-reading and
comments, both from the School of Geography and Environmental Science,
The University of Auckland.
Thanks also to Igor Drecki for his help in preparation of this material and to
Peter Arthur for his constructive suggestions and image enhancements.
Photography
All photographs and diagrams by Jacek Drecki with exception of (name,
slide number): Igor Drecki 1, 6, 10, 25, 30, 33, 34, 42, 51, 61, 62 and 76; Royal
New Zealand Air Force 38; Therkleson’s Scenic Gems 9; Internet 15.
introduction · landscape origins · volcanic landscape · erosion-deposition · glaciation · tectonism · vegetation · human impact · summary
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School of Geography & Environmental Science · The University of Auckland
© SGES, The University of Auckland, 2003
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