Journal and Chart
interpretation
A.1 Why were two small areas (see map, right) of the Encounter
Bay coastline missed on Flinders' chart?
This is an important question as one of these 'blanks' would appear to be the location of the Murray
River Mouth.
A.2 Can clues to this omission be gained from the descriptions of what was
happening at this time?
[ Clue: read extract,
following.]
 Flinders'
description of the encounter with the French
'Before two in the afternoon we stretched eastward again; and at four, a
white rock was reported from aloft to be seen ahead. On approaching
nearer, it proved to be a ship standing toward us; ... I hove to;
and learned it was the French national ship Le Géographe, under the
command of Captain Nicolas Baudin ... a boat was hoisted out, and I went
on board the French ship ... '
- Matthew Flinders in Terra Australis
[8 Apr, 1802]
(Further
information available on The Encounter in books and on-line Journal)
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Flinders' Chart, area of Murray
Mouth
Extract from
Flinders' chart, Encounter Bay
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Research
The sign is near the Murray River Mouth, the location of Goolwa Barrage,
and where a lock operates for certain hours.
B.1 What is a barrage? (a diagram may help)
B.2 What is a lock (a diagram may help)?
B.3 How are they related to the Murray River and its mouth?
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Photo 1:
Adjacent to the Murray Mouth
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Extended
discussion / interpretation
Part of the text portion of the signboard:
The Coorong is a unique coastal landform adjacent to the mouth of
Australia's largest river, the River Murray.
The Coorong consists of a series of coastal lagoons separated from the ocean
by a thin strip of coastal sand dunes. These lagoons are important feeding,
breeding, spawning and nursery areas for fish, as well as supporting one of
Australia's largest concentration of migratory wading birds.
One of the major recreational species which spawn in this region is the
popular mulloway. Generally larger, adult mulloway can be found on the ocean
side of the Coorong and smaller juveniles within the inland lagoons.
The inland waters of the Coorong range in salinity from fresh, through
brackish, to very saline, providing suitable habitats for those fish that
can tolerate a wide range of salinity. These include sharks, stingrays,
flounder, sea bream, trevally, salmon and mullet.
(mulloway and salmon pictured)
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Fishing
the Coorong
Photo 2: Signboard near the Murray
Mouth
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Read the material above carefully.
Statement
'To successfully manage fish stocks (and stocks of other species) it is
necessary for managers and authorities to
possess an understanding of coastal landforms and coastal processes.'
C.1 Critically discuss this statement, giving evidence for your
viewpoint.
C.2 As for C.1 above, in regard to the management of coastal
ecotourism.
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Research
and interpretation
D.1 Why is salt a component of the soils and rocks of the
lower Murray region?
D.2 What human activies appear to be bringing salt to the
surface?
D.3 What agricultural (and other) problems have resulted from salt buildup on the surface?
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Photo 3: Salt-encrusted lake,
Hindmarsh Island
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Research
and interpretation
For much of its lower course, the Murray flows through limstone (see photo,
right).
E.1 What is the origin of this limestone (i.e. when and how was it
formed)?
E.2 How does limestone influence agriculture of the area and
water quality of the river?
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Photo 4: Murray
River, incised meander in limestone
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Research
and interpretation
The signboard refers to the
efforts of Glossop High School students.
F.1 Where is Glossop?
F.2 What specific actions do you think these students are
carrying out?
F.3 What results do you think they hope to achieve?
F.4 What do you think are the motivations of these students?
F.5 It is possible that this (and other similar schools)
have some different courses compared with those of schools in major cities. What might be some
of these courses?
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School project: wetland
rehabilitation
Photo 5: Community
action near Berri
(school involvement in land rehabilitation)
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Research and discussion
G.1 To
what extent is the Murray River important to Australia:
(a) in term of settlement (main cities and
population of the region),
(b) in terms of agriculture (main forms of rural
production along the river),
(c) in terms of ecology (main plant and animal
communities along the river).
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H.1 In what ways have humans influenced and altered the river's
flow (both present and past)? What factors motivated these
alterations?
H.2 In what ways have these alterations contributed
to subsequent environmental problems within the Murray region?
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I.1 What is meant by the term 'Murray-Darling catchment'? To
assist your answer, draw a map, showing scale, state borders, main
tributaries, and largest cities of the region.
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J.1
'The Murray-Darling catchment (the rivers and surrounds) are important to
human culture, both Aboriginal and European.'
Research examples that illustrate this statement.
In particular, you may wish to find out aspects of the Ngarrindjeri
culture, as well as the river port history, of the lower Murray.
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Advanced Geography Topic
K.1 'The Murray River and its tributaries have a complex
geomorphic history. The overall courses of the main rivers have been
defined for millions of years. However, climate changes have altered the
detailed characteristics of the rivers.'
Evaluate this statement, providing supporting
documentation for your discussion.
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Photo interpretation
and research
 Sediment
study - upstream, along the Murrumbidgee (a major tributary of the Murray)
at Hay, NSW
There
is no section of the mid and lower river where the river flows in a straight
line; the channel constantly curves in shapes called meanders. This
is true of rivers generally.
The river
here has cut into its own flood plain; banks are relatively steep, composed
of fine particles 'bonded' together fairly firmly. A field
inspection supports this suggestion - the banks are mud, made up of
small particles (of silt and clay size - i.e. smaller than
sand). (Note: sandy banks are generally not as steep.)
L.1
Were the mud along the banks to be hardened and consolidated into rock, what
would the rock be called? (two names, depending if it is 'blocky', or if it clearly
forms narrow layers.)
[ Clue: select
from this list - breccia, claystone, conglomerate, mudstone, sandstone,
shale, siltstone.]
L.2 Describe the main features of each of the seven rock types
mentioned in L.1 above. Then rank them in sequence by particle size
(they range from coarse to fine).
L.3 Examine Photo D (right). Do the sediments seem to be at
least partly sorted (i.e. arranged in some order that is not random)?
The question should be answered in terms of particles above and below the
water level. On what basis might these particles be sorted, and how might
this come about?
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Sediment
sizes, Murrumbidgee River
Photo 6: Murrumbidgee
River scenes (southern bank, Hay, NSW)
A: A 'typical' view of the river
B: Bank undercutting (i.e. erosion by river)
C: Mudcracks alongside river, in drying sediment
D: Deposition of fine sediments on river bank
Murrumbidgee
River MAP
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L.4 Go to the MAP
of the Murrumbidgee
River at
Hay, NSW (use the Back
button to return to this page). The photos were taken at Point X. The river flows from
right to left (east to west). Study the river's course.
(a) What is the name of the feature at Y?
(b) Why do features of this type tend to have a crescent shape facing the
river (as shown)?
[ Clue: the answer relates to
the origin of these features.]
(c) How is the water level maintained in these features?
(d) Can fish live in these water features?
(e) This type of feature figures in a significant amount of Australian folk
lore. Can you elaborate? (i.e. name a story, poem or song that includes
mention of this feature, and explain what it is about? - one such song is very
famous!)
L.5 Make an estimate of a typical meander wavelength and
amplitude (in metres).
[ Clue 1: you may need to
familiarise yourself with the properties and characteristics of waves (waves
in the sea or waves studied at scool in a physics lab, and Clue 2: you will need a
ruler and data table to assist your work, also making use of the map scale.]
It is believed that during the Pleistocene rivers running across the plains
of western NSW carried more much more water than at present. What conditions
might have prevailed to give rise to this situation? How were river
wavelength and amplitude different then? How might the carrying capacity of
the rivers also have been different?
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