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{{short description|Hypothesized Neoproterozoic supercontinent from the end of the Precambrian}}
[[File:Panotiaggg.jpg|thumb|Pannotia was centred on the South Pole, hence its name.]]
'''Pannotia''' (from Greek: ''[[wikt:pan-|pan-]]'', "all", ''[[wikt:νότος|-nótos]]'', "south"; meaning "all southern land"), also known as the '''Vendian supercontinent''', '''Greater Gondwana''', and the '''Pan-African supercontinent''', was a relatively short-lived [[Neoproterozoic]] [[supercontinent]] that formed at the end of the [[Precambrian]] during the [[Pan-African orogeny]] (650–500 [[Megaannum|Ma]]), during the [[Cryogenian]] period and broke apart 560 Ma with the opening of the [[Iapetus Ocean]], in the late [[Ediacaran]] and early [[Cambrian]].<ref>{{Harvnb|Scotese|2009|loc=Reconstruction of Rodinia and Pannotia, p. 68}}</ref>
Pannotia formed when [[Laurentia]] was located adjacent to the two major South American [[craton]]s, [[Amazonian Craton|Amazonia]] and [[Río de la Plata Craton|Río de la Plata]]. The opening of the [[Iapetus Ocean]] separated Laurentia from [[Baltica]], Amazonia, and Río de la Plata.<ref>{{Harvnb|Unrug|1997|loc=pp. 3–4, Fig. 3}}</ref> InA 2022 thepaper wholeargues concept ofthat Pannotia hasnever beenfully putexisted, intoreinterpreting question by scientists who argue its existence is not supported bythe [[geochronology|geochronological]], evidence: "the supposed landmass had begun to break up well before it was fully assembled".<ref>{{Cite journal |title=Pannotia: To be or not to be? |journal=[[Earth-Science Reviews]] |lastlast1=Nance |firstfirst1=R. Damian |volume=232 |last2=Evans |first2=David A.D. |doi=10.1016/j.earscirev.2022.104128 |year=2022 |last3=Murphy |first3=J. Brendan|page=104128 }}</ref> However, the assembly of the next supercontinent [[Pangaea]] is well established.
 
==Origin of concept==
J. D. A. Piper was probably the first to propose a Proterozoic supercontinent preceding [[Pangaea]], today known as [[Rodinia]].<ref>{{Harvnb|Piper|1976}} </ref><ref>For a more detailed description of the concept(s) of the supercontinent cycle see: {{Harvnb|Nance|Murphy|Santosh|2014|loc=Indications of pre-Pangean supercontinents, pp. 6, 8}}</ref> At that time he simply referred to it as "the Proterozoic super-continent",<ref>{{Harvnb|Piper|1976|loc=Geological and Geophysical implications, p. 478}}</ref> but much later he named this "symmetrical crescent-shaped analogue of Pangaea" 'Palaeopangaea' and in 2000 he still insisted that there is neither a need nor any evidences for Rodinia or its daughter supercontinent Pannotia or a series of other proposed supercontinents since [[Archean|Archaean]] times.<ref>{{Harvnb|Piper|2000|loc=Abstract}}; {{Harvnb|Piper|2010|loc=Abstract}}</ref>▼
{{Life timeline}}
▲J. D. A. Piper was probably the first to propose a Proterozoic supercontinent preceding Pangaea, today known as [[Rodinia]].<ref>{{Harvnb|Piper|1976}} </ref><ref>For a more detailed description of the concept(s) of the supercontinent cycle see: {{Harvnb|Nance|Murphy|Santosh|2014|loc=Indications of pre-Pangean supercontinents, pp. 6, 8}}</ref> At that time he simply referred to it as "the Proterozoic super-continent",<ref>{{Harvnb|Piper|1976|loc=Geological and Geophysical implications, p. 478}}</ref> but much later he named this "symmetrical crescent-shaped analogue of Pangaea" 'Palaeopangaea' and in 2000 he still insisted that there is neither a need nor any evidences for Rodinia or its daughter supercontinent Pannotia or a series of other proposed supercontinents since Archaean times.<ref>{{Harvnb|Piper|2000|loc=Abstract}}; {{Harvnb|Piper|2010|loc=Abstract}}</ref>
 
The existence of a Latelate Proterozoic supercontinent, much different from Pangaea, was, nevertheless, first proposed by {{Harvnb|McWilliams|1981}} based on [[Paleomagnetism|paleomagnetic]] data, and the break-up of this supercontinent around 625–550 Ma was documented by {{Harvnb|Bond|Nickeson|Kominz|1984}}.<ref>{{Harvnb|Murphy|Nance|1991|loc=Introduction, p. 469}}</ref> The reconstruction of Bond et al. is virtually identical to that of {{Harvnb|Dalziel|1997}} and others.<ref>{{Harvnb|Meert|Powell|2001|loc=Fig. 1, p. 2}}</ref>
 
Another term for the supercontinent that is thought to have existed at the end of [[Neoproterozoic]] time is "Greater Gondwanaland", suggested by {{Harvnb|Stern|1994}}. This term recognizes that the supercontinent of [[Gondwana]], which formed at the end of the Neoproterozoic, was once part of the much larger end-Neoproterozoic supercontinent.<ref>{{Harvnb|Stern|1994|loc=Fig. 1, p. 321; fig. 5, p. 329}}</ref>
 
Pannotia was named by {{Harvnb|Powell|1995}},<ref>{{Harvnb|Powell|1995|p=1053}}</ref> based on the term "Pannotios" originally proposed by {{Harvnb|Stump|1987}} for "the cycle of tectonic activity common to the Gondwana continents that resulted in the formation of the supercontinent."<ref>{{Harvnb|Stump|1987|loc=Abstract}}; {{Harvnb|Stump|1992|loc=Pannotios tectonism, pp. 30–31}}</ref> {{Harvnb|Young|1995}} proposed renaming the older Proterozoic supercontinent (now known as Rodinia) "Kanatia", the [[St. Lawrence Iroquoians|St. Lawrence Iroquoian]] word from which the name 'Canada' is derived, while keeping the name Rodinia for the latter Neoproterozoic supercontinent (now known as Pannotia).<ref>{{Harvnb|Young|1995|p=154}}</ref> Powell, however, objected to this renaming and instead proposed Stump's term for the latter supercontinent.
 
[[File:Pannotia - 2.png|250px|thumb|left|An artist's impression of Pannotia, about 600 million years ago, in the [[Ediacaran]] period.]]
 
==Formation==
[[File:Pannotia.svg|thumb|Pannotia 545 Ma, view centred on the South Pole; rotated 180° relative to the reconstruction of Rodinia above, after {{Harvnb|Dalziel|1997}}<ref>{{Harvnb|Dalziel|1997|loc=Fig. 12, p. 31}}</ref>]]
The formation of Pannotia began during the [[Pan-African orogeny]] when the [[Congo Craton|Congo continent]] gotwas caughtlodged between the northern and southern halves of the previous supercontinent [[Rodinia]] some 750 Ma. The peak in this mountain building event was around 640–610 Ma, but these continental collisions may have continued into the Earlyearly Cambrian some 530 Ma. The formation of Pannotia was the result of Rodinia turning itself inside out.<ref name="Scotese-2009-Pannotia">{{Harvnb|Scotese|2009|loc=Reconstruction of Pannotia, pp. 71–72}}</ref>
 
When Pannotia had formed, Africa was located at the centre surrounded by the rest of Gondwana: South America, Arabia, Madagascar, India, Antarctica, and Australia. Laurentia, which 'escaped' out of Rodinia, [[Baltica]], and [[Siberia (continent)|Siberia]] kept the relative positions they had in Rodinia. The [[Cathaysia|Cathaysian]] and [[Cimmeria (continent)|Cimmerian terranes]] (continental blocks of southern Asia) were located along the northern margins of east Gondwana. The [[Avalonia]]n-[[Cadomian Orogeny|Cadomian]] terranes (later to become central Europe, Britain, the North American east coast, and Yucatán) were located along the active northern margins of western Gondwana. This [[orogeny]] probably extended north into the [[Ural Mountains|Uralian]] margin of Baltica.<ref name="Scotese-2009-Pannotia" />
 
Pannotia formed by [[subduction]] of exterior oceans (a mechanism called extroversion)<ref>{{Harvnb|Murphy|Nance|2013|loc=Introduction, pp. 185–187}}</ref> over a [[geoid]] low, whereas Pangaea formed by subduction of interior oceans (introversion) over a geoid high<ref>{{Harvnb|Murphy|Nance|2013|loc=Discussion, p. 191}}</ref> perhaps caused by [[superplume]]s and [[Supercontinent#Supercontinents and volcanism|slab avalanche events]].<ref>{{Harvnb|Murphy|Nance|2013|loc=Conclusions, p. 192}}</ref>
The oceanic crust subducted by Pannotia formed within the [[MirovoiMirovia]] superocean that surrounded Rodinia before its 830–750 Ma break-up and were accreted during the Latelate Proterozoic [[orogeny|orogenies]] that resulted from the assembly of Pannotia.<ref name="Murphy-etal-2009-p412">{{Harvnb|Murphy|Nance|Cawood|2009|loc=Assembly of Pannotia, pp. 412–13}}</ref>
 
One of the major of these orogenies was the collision between Easteastern and Westwestern Gondwana or the [[East African Orogeny]].<ref name="Murphy-etal-2009-p410">{{Harvnb|Murphy|Nance|Cawood|2009|loc=Development of concepts, pp. 410–11}}</ref> The [[Trans-Saharan Belt]] in West Africa is the result of the collision between the [[Saharan Metacraton|East Saharan Shield]] and the [[West African Craton]] when 1200–710 Ma-old volcanic and arc-related rocks were accreted to the margin of this craton.<ref name="Murphy-etal-2009-p412" />
600–500Between 600 and 500 Ma, two Brazilian interior orogeniesorogens gotwere highly deformed and metamorphosed between a series of colliding cratons: [[Amazonian Craton|Amazonia]], [[West African Craton|West Africa]]-[[São Luís Craton|São Luís]], and [[Sao Francisco Craton|São Francisco]]-[[Congo Craton|Congo]]-[[Kasai Craton|Kasai]]. The material that was accreted included, 950–850 Ma, [[mafic]] meta-igneous complexes and younger arc-related rocks.<ref name="Murphy-etal-2009-p412" />
 
==Break-up==
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| footer = Pannotia formed as Proto-Laurasia was added to Gondwana c. 600&nbsp;Ma (left) and broke up 550&nbsp;Ma (right) when Laurasia broke apart.<br />View centred on the South Pole.
}}
The break-up of Pannotia was accompanied by sea level rise, dramatic changes in climate and ocean water chemistry, and [[Cambrian explosion|rapid metazoan diversification]].<ref name="Murphy-etal-2009-p410" /> {{Harvnb|Bond|Nickeson|Kominz|1984}} found Neoproterozoic [[passive margin]] sequences worldwide—the first indication of a Late Neoproterozoic supercontinent but also the traces of its demise.<ref name="Meert-Lieberman-2004-p4">{{Harvnb|Meert|Lieberman|2004|loc=Results, Discussion, pp. 4–5}}</ref>
 
The [[Iapetus Ocean]] started to open while Pannotia was being assembled, 200 Ma after the break-up of Rodinia. This opening of the Iapetus and other Cambrian seas coincided with the first steps in the evolution of soft-bodied metazoans, and also made a myriad of habitats available for them; this led to the so-called Cambrian explosion, the rapid evolution of [[Cambrian explosion#Ediacaran–Early Cambrian skeletonisation|skeletalized metazoans]].<ref>{{Harvnb|Dalziel|1997|p=38}}</ref>▼
{{Harvnb|Bond|Nickeson|Kominz|1984}} found Neoproterozoic [[passive margin]] sequences worldwide – the first indication of a Late Neoproterozoic supercontinent but also the traces of its demise.<ref name="Meert-Lieberman-2004-p4">{{Harvnb|Meert|Lieberman|2004|loc=Results, Discussion, pp. 4–5}}</ref>
 
▲The [[Iapetus Ocean]] started to open while Pannotia was being assembled, 200 Ma after the break-up of Rodinia. This opening of the Iapetus and other Cambrian seas coincided with the first steps in the evolution of soft-bodied metazoans, and also made a myriad of habitats available for them; this led to the so-called Cambrian explosion, the rapid evolution of [[Cambrian explosion#Ediacaran–Early Cambrian skeletonisation|skeletalized metazoans]].<ref>{{Harvnb|Dalziel|1997|p=38}}</ref>
 
[[Trilobite]]s originated in the Neoproterozoic and began to diversify before the break-up of Pannotia 600–550&nbsp;Ma, as evidenced by their ubiquitous presence in the fossil record, and the lack of [[vicariance]] patterns in their lineage.<ref name="Meert-Lieberman-2004-p4" />
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* [[Plate tectonics]]
* [[Supercontinent cycle]]
* [[Pan-African orogeny]]
 
==References==
 
===Notes===
{{Reflist|20em}}
 
===Sources= References ==
{{Refbegin|30em}}
* {{Cite journal
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| title = Precambrian Plate Tectonics
| editor-last = Kröner | editor-first = A.
| year = 1981 | journalseries = Developments in Precambrian Geology | volume = 4
| isbn = 9780080869032 | doi = 10.1016/S0166-2635(08)70031-8 }}<!-- {{Harvnb|McWilliams|1981}} -->
* {{Cite journal
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| chapter = Construction of the Pacific margin of Gondwana during the Pannotios cycle
| title = Gondwana Six: Structure, tectonics and geophysics
| journal = Washington DC American Geophysical Union Geophysical Monograph Series
| editor-last = McKenzie | editor-first = G. D.
| year = 1987 | series = American Geophysical Union Monograph | volume = 40 | pages = 77–87
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* {{Cite web |url=http://www.geodynamics.no/GMAP/Methods/Continent_Outlines.htm |title=Palaeozoic Continent Margins: Late Cambrian (500&nbsp;Ma) |last=Torsvik |first=Trond Helge |access-date=18 June 2010 |archive-date=23 July 2011 |archive-url=https://web.archive.org/web/20110723122650/http://www.geodynamics.no/GMAP/Methods/Continent_Outlines.htm |url-status=dead }}
* {{Cite journal
| last1 = Stampfli | firstfirst1 = G. M.
| last2 = von Raumer | first2 = J. F.
| last3 = Borel | first3 = G. D.
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[[Category:Former supercontinents]]
[[Category:Cryogenian]]
[[Category:Ediacaran]]
[[Category:Cambrian]]
[[Category:Plate tectonics]]
[[Category:Proterozoic]]
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