Elsevier Encyclopedia of Geology - vol I A-E
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metasedimentary gneiss in the Mullingarra Complex
has been dated to 2181 Ma (Figure 2). This is con-
sistent with Sm–Nd model ages of 2280–2030 My
from the Northampton and Mullingarra complexes,
and boreholes in the Perth Basin, indicating the in-
volvement of Early Palaeoproterozoic crust in the
evolution of the orogen.
North Australian Craton
In the North Australian Craton, the presence of prob-
able Archaean to Early Palaeoproterozoic cratons
and continental blocks within the basement is in-
ferred from geophysical datasets. Latest Neoarchaean
basement is exposed as granite and granite gneiss
within the Rum Jungle and Nanambu complexes in
the Pine Creek Orogen (Figure 2). These basement
inliers are overlain by arkosic rocks of the Namoona
Group and the shallow-marine carbonates and mud-
stones and siltstones of the Mount Partridge Group
deposited before 1885 Ma. Archaean crust of the
Lucas Craton is also present as inliers partly covered
by arkosic and conglomeratic rocks within the
Browns Range Dome and the Billabong Complex in
the Granites–Tanami Complex (Figure 2). The pres-
ence of further concealed Archaean crust that may be
as old as 3600 My is indicated by Sm–Nd and Pb
isotopic data, together with a U–Pb detrital zircon
studies.
Awidespread orogenic event took place throughout
the North Australian Craton between 1910 and
1790 Ma. This event, originally defined with a shorter
duration (between 1870 and 1840 Ma), has been
termed the ‘Barramundi Orogeny’. It was interpreted
as an intracratonic event involving a linked polygonal
system of rifts and sag basins, which evolved rapidly
to became the sites of crustal shortening, volumin-
ous magmatism, and high-temperature/low-pressure
metamorphism. More recent interpretations have
suggested that the ‘Barramundi Orogeny’ represents
a series of linked collisional events that assembled the
North Australian Craton. Based on similarities that
can be recognized with the evolution of the Trans-
Hudson Orogen, the North Australian Craton may
have been originally contiguous with Laurentia,
which would have lain to the north.
Figure 3 Assembly of the North Australian and South Australian cratons, 1900–1730 Ma.
AUSTRALIA/Proterozoic 211
In the north-western part of the craton, the King
Leopold and Halls Creek orogens were initiated
by rifting along the western margin of the Lucas
Craton 1910 Ma. Renewed rifting is represent-
ed by deposition of the lower Halls Creek Group
1880 Ma. Accretion of Neoarchaean to early
Palaeoproterozoic continental fragments to the
opposing eastern edge of the Kimberley Craton oc-
curred before 1910 Ma. Turbidites derived by ero-
sion from these fragments were deposited 1870 Ma.
Deformation, metamorphism, and extensive felsic
and mafic magmatism (Whitewater Volcanics, Paper-
bark Supersuite) occurred during the Hooper Orogeny
(1865–1850 Ma) (Figure 3). The central part of the
orogen (Tickalara Metamorphics) formed 1865 Ma
as an oceanic island arc above a north-west-dipping
subduction zone. Layered mafic–ultramafic intrusions
were emplaced 1855 Ma. Deformation and meta-
morphism to high grade 1845 Ma followed intru-
sion of numerous felsic and basic to intermediate
sheetlike bodies during convergence and collision of
the arc with the Kimberley Craton. Alkaline volcan-
ism between 1870 and 1850 Ma marked further
rifting along the Lucas Craton margin. A submarine
fan deposited turbiditic rocks of the upper Halls Creek
Group parallel to the craton margin.
Eruption of felsic and mafic volcanic rocks during
rifting of the accreted arc 1840 Ma was accom-
panied by the emplacement of further layered
mafic–ultramafic intrusions. Continued subduction
of oceanic crust to the north-west led to collision
and suturing of the Kimberley Craton with the rest
of the North Australian Craton by 1820 Ma, during
the Halls Creek Orogeny (Figure 3). Folding and
thrusting accompanied metamorphism. During and
immediately following collision, plutons of granite
and gabbro were intruded to form the Sally Downs
Supersuite (1835–1805 Ma) at the same time as
the intrusion of additional large, layered mafic–
ultramafic bodies. As the Sally Downs Supersuite was
being intruded, the Speewah Group was deposited
1835 Ma in a foreland basin on the Kimberley
Figure 4 Final assembly of the cratonic elements of Proterozoic Australia, 1730–1600 Ma.
212 AUSTRALIA/Proterozoic
Craton. The overlying 1800-My-old Kimberley
Group was derived from the north. The intrusion of
the voluminous Hart Dolerite 1790 Ma may
be related to a continental breakup, possibly from
Laurentia, centred to the north (Figure 3).
To the south-east of the Halls Creek Orogen, the
Granites–Tanami Complex and the northern part of
the Arunta Inlier developed on the thinned Archaean
to Early Palaeoproterozoic basement of the Lucas
Craton (Figure 3). The <1877-My-old MacFarlane
Peak Group and Dead Bullock Formation represent a
rift, followed by a sag basin, with the overlying
<1840-My-old Killi Killi Formation and Lander
Rock beds turbidites being deposited during the
Tanami Orogeny, which probably represents a
within-plate response to the collisional Halls Creek
Orogeny to the north-west. The orogenic event was
followed by voluminous bimodal and granitic mag-
matism between 1825 and 1790 Ma in both the
Granites–Tanami Complex and the northern Arunta
Inlier, including the high-temperature/low-pressure
metamorphism, deformation, and granite magmatism
of the Mount Stafford tectonic event 1820 Ma
(Figure 3). Over the same time period, granite was
intruded into the southern part of the Halls Creek
Orogen. The Lichfield Complex is the north-eastward
continuation of the Halls Creek Orogen, and the Pine
Creek Orogen may represent a within-plate tectonic
setting similar to that of the Granites–Tanami Com-
plex (Figure 3). The 1885-My-old South Alligator
Group and the overlying Finniss River Group repre-
sent a transition from shallow-marine sediments to
deep-marine turbidites, possibly related to the onset
of the ‘Barramundi Orogeny’ in the form of the Nim-
buwah event 1880–1860 Ma. Further deformation,
equivalent to the Halls Creek and Tanami orogenies,
accompanied extensive intrusion of granites between
1840 and 1820 Ma.
Figure 5 Docking with Laurentia, 1600–1200 Ma.
AUSTRALIA/Proterozoic 213
In the Mount Isa Inlier, the Kalkadoon–Leichhardt
Belt from 1870–1840 Ma, now regarded as the
remnants of a magmatic arc, represents the ‘Barra-
mundi Orogeny’ (Figure 3). Along the southern edge
of the northern Arunta Inlier, the Atnarpa igneous
complex from 1880–1860 Ma has been interpreted
as being generated by subduction at a convergent
plate margin. Rocks of ‘Barramundi Orogeny’ age
are also present in the Tennant Creek Inlier, where
turbidites of the <1860-My-old Warramunga Forma-
tion are intruded by 1850-My-old granites and are
overlain by 1845-My-old felsic volcanic rocks
(Figure 3).
Between 1780 and 1730 Ma, a magmatic arc de-
veloped along the southern margin of the northern
Arunta Inlier, above a northward-dipping subduction
zone. The high-temperature/low-pressure metamor-
phism associated with the Early Strangways Orogeny
1780–1770 Ma overlapped the development of the
magmatic arc. This event is contemporaneous with
the Yapungku Orogeny (1790–1760 Ma) in the oppos-
ing margin of the West Australian Craton (Figure 3),
and together they may record the suturing of those
cratons, although probably not in their current
configuration. The Late Strangways Orogeny (1740–
1730 Ma) was accompanied by moderate-pressure
metamorphism. Subduction of oceanic crust associ-
ated with the Early and Late Strangways orogenies
was at a low angle to the north. A back-arc setting
resulted, causing southward tilting within the crust to
the north of the Arunta Inlier, together with high heat
flows and extension followed by thermal subsidence.
Between 1800 and 1670 Ma, two cycles of extensive
volcano-sedimentary basin formation took place
across the North Australian Craton, separated by a
period of uplift and erosion. The first cycle (1800–
1750 Ma) is represented by the development of the
Leichhardt Superbasin (Figure 3). Bimodal volcan-
ism, dominated by flood basalts, and fluvial to shal-
low-marine sedimentation occurred within the lower
parts of the McArthur Basin successions (lower Kath-
erine River Group, lower Donydji Group, Groote
Eylandt Group, and lower Tawallah Group), the
upper Hatches Creek Group in the Tennant Creek
Inlier, and the lower parts of the successions within
the Mount Isa Inlier (Haslingden Group, Quilalar
Formation, Magna Lyn Metabasalt, Argylla Volcan-
ics, Malbon Group, and Corella Formation). In the
Figure 6 Intracratonic reactivation, 1200–900 Ma.
214 AUSTRALIA/Proterozoic
Mount Isa Inlier, rifting in the upper crust was accom-
panied by the development of a regional-scale exten-
sional shear zone, high-temperature/low-pressure
metamorphism, and igneous intrusion (the 1742-
My-old Wonga batholith) in the mid-crust.
A period of basin inversion 1730 Ma produced a
regionally extensive unconformity before the onset
of the second depositional cycle (1730–1690 Ma),
which formed the Calvert Superbasin, and the third
depositional cycle (1665–1575 Ma), which formed
the Isa Superbasin (Figure 4). The Sybella batholith
was intruded in the Mount Isa Inlier 1665 Ma.
Again the successions are characterized by bimodal
volcanics and rift-related sediments in the McArthur
Basin (upper Katherine River Group, upper Donydji
Group, Parsons Range Group, Spencer Creek Group,
and upper Tawallah Group), the Mount Isa Inlier
(Fiery Creek Volcanics, lower McNamara Group,
lower Mount Isa Group, Kuridala Formation, and
lower Soldiers Cap Group), and the Georgetown
Inlier (lower Etheridge Group). The Redbank Thrust
separates the southern Arunta Inlier from the
northern Arunta Inlier. The Argilke tectonic event
represents a significant magmatic and metamorphic
event 1680 Ma. A major north-directed thrust
system, associated with granite intrusion, took place
1610 Ma during the Chewings Orogeny (Figure 4).
South Australian Craton
In the Gawler Craton, Archaean gneissic rocks of
the Sleaford and Mulgathing complexes were
deformed, metamorphosed to granulite facies, and
intruded by granites during the Sleafordian Orogeny
2550–2400 Ma (Figure 2). At the eastern margin
of the Gawler Craton, orthogneiss of the Miltalie
Gneiss (2003 Ma) is unconformably overlain by
shallow-water continental shelf deposits. These in-
clude metamorphosed amphibolite facies mafic vol-
canics, carbonates, and iron formation of the
Hutchison Group >1860 Ma (Figure 2). The Kimban
Orogeny has affected much of the Gawler Craton. It
has been regarded as consisting of three tectonic
events and dates from 1850 to 1690 Ma. It is
contemporaneous with the Capricorn Orogeny and
Figure 7 Rifting from Laurentia, collision with India, 900–520 Ma.
AUSTRALIA/Proterozoic 215
the Yapungku Orogeny in the West Australian
Craton, and the Early and Late Strangways orogenies
in the North Australian Craton, and may represent a
series of intraplate and plate margin events reflecting
convergence and accretion of the Gawler Craton to
what was then the south-eastern North Australian
Craton.
Intrusive rocks of the Donnington Granitoid
Suite (1850 Ma) were emplaced synchronously
with a deformation event that has been regarded as
an early tectonic phase of the Kimban Orogeny
(Figure 3). The second phase of the orogeny produced
medium- to high-pressure/high-temperature meta-
morphism and associated deformation. Felsic and
Table 1 Summary of Proterozoic tectonic events in Australia
216 AUSTRALIA/Proterozoic
bimodal volcanics and interlayered metasedimentary
rocks of the Myola Volcanics and the Broadview
Schist, and the Peake Metamorphics were deposited
on the Gawler Craton 1790 Ma, contemporaneous
with syntectonic granitic rocks of the Lincoln
Complex. Further volcanic rocks and metasedimen-
tary rocks were deposited between 1765 and
1735 Ma (McGregor Volcanics, Moonabie For-
mation, and Wallaroo Group). The third phase of
the orogeny took place between 1745 and 1690 Ma
and involved deformation, medium-grade meta-
morphism, and further granite intrusion (Figure 4).
Following accretion to the North Australian
Craton, the site of subduction may have moved to
Table 1 Continued
AUSTRALIA/Proterozoic 217
the south-western Gawler Craton (Figure 4) with the
development of the first tectonic episode of the
Kararan Orogeny (1710–1670 Ma) and the intrusion
of voluminous granitic rocks of the Tunkillia Suite in
a possible back-arc setting. The second tectonic
phase involved the intrusion of the St Peter Suite
(1630–1608 Ma) as a continental magmatic arc, and
probably reflects accretion of continental blocks
from the west, now buried beneath the Phanerozoic
Eucla Basin. The Kararan Orogeny is coincident with
the Argilke and Chewings events in the southern
Arunta Inlier, with the deposition of the Mount
Barren Group and the reactivation of the Capricorn
Orogen in the West Australian Craton, and with
the development of the Calvert and Isa superbasins
on the North Australian Craton (Figure 4). In the
Curnamona Craton, the shallow-marine, immature
clastic sedimentary rocks and bimodal volcanics of
the Willyama Supergroup were deposited between
1715 and 1645 Ma. They may represent a con-
tinuation of the Calvert and Isa superbasins that has
subsequently been displaced dextrally during the
Mesoproterozoic (Figure 3).
Mesoproterozoic – The Assembly
of Rodinia (1600–1000 Ma)
Along the eastern edge of the North Australian
Craton and in the north-eastern part of the South
Australian Craton, a major orogenic event took
place between 1600 and 1500 Ma (Figure 5). This
event included the Isan Orogeny (1560–1500 Ma) in
the Mount Isa Inlier, the Ewamin Orogeny (1550 Ma)
in the Georgetown Inlier, the Olarian Orogeny
(1590 Ma) in the Curnamona Craton, and the late
event (1565-1540 Ma) of the Kararan Orogeny. Sub-
duction was to the west, culminating in collision
with a continent to the east that may have been
Figure 8 Significant mineral and diamond (Di) deposits in the Proterozoic of Australia.
218 AUSTRALIA/Proterozoic
Laurentia. In the Georgetown Inlier, the felsic rocks
of the Croydon Volcanic Group and the Forest Home
Supersuite represent a magmatic arc. Further to the
west, the eruption of the voluminous Gawler Range
Volcanics, and the intrusion of the Hiltaba Suite in the
Gawler Craton, occurred between 1600 and
1580 Ma, contemporaneously with the early stages
of this orogenic event.
Elsewhere in central and western Australia, Meso-
proterozoic rocks of poorly understood tectonic set-
ting include medium- to high-grade 1600-My-old
quartzofeldspathic gneisses (Olia Gneiss) to the north
of the Woodroffe Thrust in the Musgrave Complex.
These were intruded by granitic rocks 1500 Ma,
before being metamorphosed 1400 Ma. South of
the Woodroffe Thrust, metasedimentary gneisses
and felsic and mafic orthogneisses ( 1550 and
1330 Ma) represent a separate terrane. Granulites in
the Birksgate Complex at the northern margin of
the South Australian Craton were derived from
metamorphism of felsic volcanics and sedimentary
rocks (1600–1300 Ma). Uplift along the Redbank
Thrust Zone at the northern margin of the southern
Arunta Inlier took place 1500–1400 Ma (Anmatjira
uplift phase). The eastern Tabletop Terrane of the
Rudall Complex is formed by metasedimentary and
metavolcanic rocks intruded by granitoids that date
to 1475 to 1290 Ma.
On the North Australian Craton, clastic and car-
bonate sedimentary rocks of the Birrindudu Group
were deposited in the Birrindudu Basin 1560 Ma,
unconformably overlying the Granites–Tanami Com-
plex. In the Kimberley region, the Mount Parker
Sandstone and the Bungle Bungle Dolomite in the
Osmand Basin, and the Crowhurst Group and the
Bastion Group, may be equivalent to the rocks of
the Birrindudu Basin. The Roper Group and the
South Nicholson Group were deposited in the intra-
cratonic Roper Superbasin between 1490 and
1430 Ma, and subsidence may be related to late
stages of the Isan Orogeny, and to the Anmatjira
uplift phase in the Arunta Inlier (Figure 5). The intra-
cratonic Cariewerloo Basin (1450 Ma) developed
on the South Australian Craton. On the West
Australian Craton, the Edmund Group, the lower
part of the Bangemall Supergroup, was deposited in
the intracratonic Edmund Basin after 1600 Ma. Ini-
tial deposition was restricted to narrow rift basins
before the development of a broad, marine basin.
Extensive intrusion of dolerite sills into the Edmund
Group took place 1465 Ma.
The Albany–Fraser Orogen developed between the
South Australian Craton and the West Australian
Craton (Figures 5 and 6). It has been interpreted
as part of a Grenvillian collisional orogeny
(1345–1140 Ma) that originally extended through
the Musgrave Complex and possibly the now dis-
placed eastern Rudall Complex, separating the
South Australian Craton from the combined West
and North Australian cratons. This event has been
interpreted as marking the final assembly of Pro-
terozoic Australia as part of the Rodinia Supercontin-
ent. Two distinct tectonic stages took place in the
Albany–Fraser Orogen, with the first producing de-
formation, high-grade metamorphism, and granitic
magmatism between 1345 and 1260 Ma. The granu-
lite facies layered mafic intrusions of the Fraser
Complex crystallized 1300 Ma. The second phase
produced further granulite facies metamorphism and
deformation 1214 Ma and subsequent granite in-
trusion between 1190 and 1140 Ma. In the Tabletop
Terrane of the Rudall Complex, granitic magmatism
occurred 1300 Ma, whereas in the southern part of
the Musgrave Complex, granulite facies metamor-
phism occurred 1200 Ma, with the intrusion of
granitic rocks 1190 Ma. Granitic rocks were also
intruded into the southern Arunta Inlier during the
Teapot magmatic event between 1200 and 1100 Ma.
In northern Australia, the 1200-My-old Auvergne
Group and the Carr Boyd Group were deposited in
the Victoria River and Carr Boyd Basins, respectively
(Figure 6).
The Collier Group, the upper part of the Bangemall
Supergroup, was deposited in the Collier Basin on
the West Australian Craton and, together with the
underlying Edmund Group, was intruded by a suite
of syn-depositional dolerite sills 1080 Ma. Large,
layered mafic–ultramafic intrusions forming the
Giles Complex (1080 Ma) were intruded into the
Musgrave Complex, followed by the eruption of
the mafic and felsic volcanic rocks of the Bentley
Supergroup 1080–1060 Ma. Together with the
intrusion of the contemporaneous Stuart and Kulgera
dyke swarms, the extensive mafic magmatism of
1080–1060 Ma has been described as a Large
Igneous Province, and may represent the influence
of a mantle plume centred beneath the Musgrave
Complex (see Large Igneous Provinces).
In the Pinjarra Orogen, metasedimentary rocks
in the Northampton Complex and Mullingarra
Complex that may have had their source in the
Albany–Fraser Orogen were metamorphosed, de-
formed, and intruded by granites between 1080
and 990 Ma. They are probably allochthonous and
may have been transported and accreted in their
present position by dextral movement along a proto-
Darling Fault prior to 755 Ma (Figure 6). The pro-
tolith to 1090-My-old granitic orthogneiss in the
Leeuwin Complex may have a syn-collisional origin.
Intracratonic reactivation of the King Leopold, Halls
AUSTRALIA/Proterozoic 219
Creek, and Capricorn orogenic belts took place be-
tween 1000 and 900 Ma during the Yampi and
Edmundian orogenies (Figure 6).
Neoproterozoic-Proterozoic Australia
in Rodinia (1000–545 Ma)
The Centralian Superbasin developed throughout
much of Proterozoic Australia from 830 Ma, either
as an extensive intracratonic sag basin or as a series of
interconnected basins that lapped onto intervening,
emergent basement highs (Figure 7). The Adelaide
Rift Complex developed to the south-east at the
same time, possibly centred over a mantle plume.
The lower part of the depositional succession in the
superbasin, Supersequence 1, is contemporaneous
with the intrusion of the Amata and Gairdner mafic
dykes in the Gawler Craton and eastern Musgrave
Complex, and the volcanics of the Callana Group in
the Adelaide Rift Complex. Supersequence 1 is char-
acterized by a basal sand sheet, overlain by stroma-
tolitic carbonates and evaporates that are correlated
throughout the component basins of the superbasin
(Officer Basin, Amadeus Basin, Ngalia Basin, Geor-
gina Basin, Wolfe Creek Basin, Louisa Basin, and
Murraba Basin). Siliciclastic rocks of the Rocky
Cape Group and the Burnie Formation in west
Tasmania may be equivalent to Supersequence 1,
deposited prior to the Wickham Orogeny 760 Ma.
Deposition of Supersequence 1 was followed by
a period of tectonic activity, the Areyonga movement,
which may represent the breakup of Rodinia as
Laurentia rifted away from the eastern margin of
Proterozoic Australia to form the proto-Pacific
Ocean. The northern part of the Adelaide Rift Com-
plex between the Gawler and Curnamona Cratons
has been interpreted as a failed arm, but there is no
evidence of the development of an adjacent passive
margin at this time. The main locus of Rodinia
breakup may have developed much further to the
east, now buried within the Tasmanides. Tilting and
flexuring of basement fault blocks to the west within
the Centralian Superbasin was controlled by the
reactivation of major structures such as the Redbank
Thrust, and a proto-Woodroffe Thrust. Widespread
folding, uplift, and erosion took place within the
basins. The 755-My-old Mundine Well dyke swarm
was intruded into the West Australian Craton and the
adjacent Northampton Complex.
Supersequece 2 is restricted to northern and central
Australia and is marked by glacigene deposits correl-
ated with the Sturtian glaciation 700 Ma in the
Adelaide Rift Complex. As sea-level rose, the glacial
deposits were overlain by silt and mud deposited in
a shallow epeiric sea. This was followed by a further
period of uplift and erosion, the South Range
Movement, and by the emplacement of the 680- to
640-My-old Mount Crofton Granite and associated
intrusions into the Lamil Group of the Yeneena Basin
in the north-western part of the Paterson Orogen.
Supersequence 3 is also marked by glacigene deposits,
which extend into the Kimberley region and the north-
west Officer Basin. These are correlated with the
600-My-old Marinoan glaciation in the Adelaide
Rift Complex. Again, rising sea-levels and the estab-
lishment of a shallow epeiric sea followed glaciation.
Supersequence 4 is dominated by sandstone and
conglomerate deposited in submarine fan, deltaic,
fluvial, and alluvial fan settings in local foreland
basins. These are associated with the development
of intracratonic orogenies, which resulted from the
reactivation of the ancient sutures between the North
Australian Craton, the West Australian Craton, and
the South Australian Craton during the Paterson and
Petermann Ranges orogenies 550 Ma (Figure 7). In
the Kimberley region, the King Leopold Orogeny
reactivated the suture between the Kimberley Craton
and the rest of the North Australian Craton at about
the same time. Large dextral strike–slip movements
produced folding and thrusting in the Musgrave
Complex, with the exhumation of eclogite facies
rocks as part of a crustal-scale flower-type structure.
The Musgrave Complex now truncates the Albany–
Fraser Orogen, and may have been displaced to the
west at this time, extending as far as the Mesoproter-
ozoic Tabletop Terrane of the Rudall Complex, with
which the Warri–Anketell Gravity Ridge connects it
beneath the Centralian Superbasin.
In the Pinjarra Orogen at the western margin of
Proterozoic Australia, Leeuwin Complex orthogneisses
from 1090 and 800–650 Ma were metamorphosed
at upper amphibolite to granulite facies conditions
540 Ma. Further granitic rocks were intruded 540–
520 Ma. These events were coincident with sinistral
tectonic transport of the Leeuwin Complex along the
Darling Fault during an oblique collision of Australia
with India (Figure 7). This collision may be responsible
for the contemporaneous intracratonic reactivations
that produced major unconformities at the base of the
Phanerozoic basins overlying Proterozoic Australia to
the west of the Adelaide Rift Complex. An extensional
margin developed to the east of the Adelaide Rift Com-
plex between 650 and 550 Ma, and is now exposed
in Tasmania and western Victoria (Figure 7). It is
marked by the intrusion of a dolerite dyke swarm, the
eruption of tholeiitic basalts, and the deposition of
associated volcanogenic sediments, carbonates, and
shallow-water siliciclastics. This margin was involved
in an arc–continent collision 505 Ma during the
Delamarian Orogeny, initiating the development of
220 AUSTRALIA/Proterozoic