The Superior Craton is a stable crustal block covering Quebec, Ontario, and southeast Manitoba in Canada, and northern Minnesota in the United States. It is the biggest craton among those formed during the Archean period. [1] A craton is a large part of the Earth's crust that has been stable and subjected to very little geological changes over a long time. [2] The size of Superior Craton is about 1,572,000 km2. [3] The craton underwent a series of events from 4.3 to 2.57 Ga. These events included the growth, drifting and deformation of both oceanic and continental crusts. [1]
Researchers have divided the Superior Craton into many different domains based on rock types and deformation styles. [4] These domains (grouped into western and eastern superior provinces), include the North Superior Superterrane and Wawa Terrane, among others [4] (shown in the table below).
Studies on the formation of the Superior Craton varied in progress between the western and the eastern part. For the western part, five major orogenies were involved. They include the Northern Superior Orogeny (2720 Ma), the Uchian Orogeny (2720–2700 Ma), the Central Superior Orogeny (2700 Ma), the Shebandowanian Orogeny (2690 Ma), and the Minnesotan Orogeny (2680 Ma). [4] For the eastern part, two models are suggested. The first model by Percival and Skulski (2000) focuses on the collision between the terranes. [5] The second model by Bédard (2003) [6] and Bédard et al. (2003) [7] focuses on the effect of an active anorogenic magmatic activity.
The Superior Craton covers central Canada; it occupies the northern and central part of Quebec, extending across the central and the southern part of Ontario, and also covers southeast Manitoba, with its tip reaching the boundary between the U.S. states of South Dakota and Minnesota. [8]
The Archean Superior Craton extends over 1572000 km2 of the North American continent. [3] Forming the core of the Canadian Shield, the Archean Superior craton is encompassed by early Proterozoic orogens. [1] The western to the northeastern part of the craton is bound by the Trans-Hudson orogens. [9] To the eastern and the southeastern side are the neighbouring Grenville orogens. [4] The southern side meets the Keweenawan rift, while the southernmost tip of the craton in Minnesota reaches the Central Plain orogen. [10]
Regarding the faults, there are three major trends of subparallel faults slicing the craton into linear subprovinces. In the northwestern part, faulting occurs in a west–northwest direction. The northeastern part has northwest-trending faults. [8] The faults in the remaining southern part possess an east–west direction. [4]
The craton-forming terranes are created from very diverse settings, such as oceanic arc, ancient forearc, oceanic tectonic melange, uplift within the craton, fold-thrust belt and extra. Common among them is that these features were mostly formed in a compression setting.
Some terranes, such as the Western Wabigoon Terrane, are formed from the setting of an oceanic arc. An oceanic arc is a chain of volcanoes which formed above and parallel to the subduction zones. Due to tectonic activities in the Earth, the relevant continental and oceanic crusts collided before 2.70 Ga. [1] The denser oceanic crust subducted underneath the continental crust and melted into the mantle, which generated more magma. The huge amount of magma then rose up, penetrated through the crust above and erupted. The continuous eruption of volcanic material cooled down and accumulated around the centers of eruption, forming a chain of volcanoes in the shape of an arc. [11]
Some terranes, such as the Quetico Terrane, were forearcs in the past. A forearc is the region between the volcanic arc and the subduction zone. It includes several components, including the subduction trench, the outer arc high of the oceanic crust, the accretionary wedges, and the sedimentary basin. The outer arc high is formed by the flexural upward motion of the oceanic crust edge before it enters the subduction zone. The accretionary wedges are formed from the accumulation of marine sediment scraped off from the oceanic crust before it is subducted. The sedimentary basin is formed from the accumulation of erosive material from the volcanoes, which lying flatly between the volcanoes and the topographic high of the accretionary wedge. [11]
Some terranes, such as the Kapuskasing Uplift, were formed from the uplifting of the crustal block. For example, during 1.85 Ga, the American Midcontinent and the Superior Craton collided. The collision between the two cratons triggered an Archean reverse fault, the Ivanhoe Lake fault. The upward movement of the hanging wall causes the uplift of a crustal block, known as the Kapuskasing Uplift. [12]
Some terranes, such as the Pontiac Terrane, were previously a fold-thrust belt. A fold-thrust belt is a zone consisting of a series of thrusts (reverse faults) and fault-bend folds separated by main thrust faults. The fold-thrust belt is formed in a compression setting like crust collision. when the crust is compressed, thrusts dipping towards where the compression comes formed. The hanging walls of the thrusts slide up along the fault plane and stacks above the footwall, forming a ramp anticline or fault-bend fold. [13]
The Superior Province can be divided into three parts. The first part is the northwestern region characterized by high-grade gneiss, such as Minto and Pikwitonei. [8] [14] The second part is the northeastern region, which is characterized by pervasive metamorphic rocks of granulite-facies. [8] The last part is the southern region like the Minnesota River Valley, which are metavolcanic or metasedimentary subprovinces with an east–west orientation. [8] [14]
The general geological characteristics of the terranes are listed below.
| Subprovince | Age | Dominating rock | Possible tectonic event | Mineral deposit |
|---|---|---|---|---|
| Western Superior Province | ||||
| Northern Superior Superterrane (NSS) | - Granitic and gneissic rocks [15] - Mafic-intermediate volcanic rocks [4] [16] [17] | - Granitoid magmatism [18] - Amphibolite-forming metamorphism caused by tectonic accretion [4] | - Lode gold deposits [19] - Diamond-containing kimberlite pipes [19] | |
| Oxford-Skull Domain (OSD) | - Basalt (Hayers River Assemblage) [20] - Volcaniclastic rocks (Oxford Lake assemblage) [20] - Underlain by tonalitic, granodioritic, granitic pluton with mafic intrusion [4] | - Oceanic setting [4] - Sealed the sediment after the collision of NSS and NCS [4] | - Lode gold deposits [21] (like Monument Bay gold deposit) | |
| North Caribou Superterrane (NCS) | - Plutonic base overlain by arc sequences [22] - Pervasive granitic to tonalitic pluton in the central region [4] | - Dominating plutonism [4] | - Gold deposits (like Red Lake Gold Camp) [4] - Massive sulphide deposits [23] | |
| English River Domain (ERT) | - Sedimentary rocks like wackes [24] | - Related to the suture of the NCS and WRT [26] | / | |
| Winnipeg River Terrane (WRT) | - Gneiss and foliated tonalite [27] [28] [29] - Granite [28] | - Tonalitic plutonism followed by granitic plutonism [4] | - Iron deposits [4] [30] | |
| Wabigoon Terrane (WwT/EwT) | - Mafic volcanic rocks and tonalitic pluton in the West [31] - Greenstone belts intruded by granitoid pluton in the East [4] | - Oceanic arc setting in the West [32] [33] [34] [35] - Continental margin setting in the East [36] | / | |
| Quetico Terrane (QT) | - Mainly greywacke, migmatite, granite [4] - Metarsedimentary successions intruded by tonalite, [4] nepheline, syenite, carbonatite [37] and granite [38] | - Ancient forearc [31] [39] [40] | / | |
| Wawa Terrane (WT) | - Calc-alkalic to alkalic rocks [41] | - Oceanic tectonic mélange [42] [43] [44] | - Michipicoten-Mishubishu belt (Fe, Au, Cu and minor Ni) [45] - Shebandowan-Schreiber belt (Fe, Au, [45] VMS, [46] Ni) [47] | |
| Kapuskasing Uplift (KU) | - Tonalite, paragneiss and anorthosite | - Intracratonic Uplift [48] | / | |
| Eastern Superior Province | ||||
| Abitibi Terrane (AT) | - North: Layered-intrusion-related volcanic rocks [4] [49] - Central: Plutonic rocks and minor volcanic rocks [50] - South: Younger greywackes, conglomerate and alkaline volcanic rocks [51] | / | - North: Massive sulphide deposits, Cu-Zn vein deposits, lode gold deposits [4] - Central: Massive sulphide deposits and vein gold deposits [50] - South: Gold deposits, Cu-Zn massive sulphide deposits, intrusive Ni deposits, and minor porphyry deposits [4] [52] | |
| Pontiac Terrane (PT) | - North: schists and paragneiss [53] - South: volcanic rocks [53] | - Fold-thrust belt [54] | - Quartz-vein-hosted gold deposits [4] | |
| Opatica Subprovince (OcS) | - Tonalite, granodiorite, granite and pegmatite [55] [56] [57] | - West-verging shearing followed by south-vergent movement [57] | - Volcanogenic massive sulphide (VMS) deposits, Cu-Au vein deposits, Intrusion-hosted Ni-Cu deposits and iron formation [4] | |
| Opinaca Subprovince (OnS) | - metagreywacke [58] - massive leucogranite intrusion [59] | / | - Rare metals in peraluminous granites and pegmatites [4] | |
| Ashuanipi Complex (AC) | - Tonalite and diorite [60] - Granulite [61] - Intrusion of diatexite, [61] syenite, granodiorite and granite [4] [62] | / | / | |
| La Grande Subprovince (LG) | - Gneissic basement [63] | / | - Porphyry and igneous mineralization [4] | |
| Bienville Subprovince (BS) | - North: granitic and granodioritic intrusions [64] | / | / | |
| Northeastern Superior Province(NESP) | - I: tonalite and tonalitic gneiss [4] - II: pyroxene-bearing plutonic rocks [4] - IV: metasedimentary and pyroxene-bearing pluton [66] - V: pyroxene-bearing pluton with minor tonalite [4] - VI: magnetic pyroxene-bearing pluton [67] - VII: tonalitic complex [7] [6] | / | - Syngenetic: Algoma-type iron formation, volcanogenic massive sulphide, Ni-Cu deposits, Fe-Ti-V deposits (hosted by mafic intrusions), and U-Th-Mo bearing porphyry deposits [4] - Epigenetic: Cu, Ni, Ag, Au, rare earth elements (REE) and limited U deposits [4] | |
Research of the Superior Craton in the past focused on how the western part formed. This leaves uncertainties in the linkage between the west and the east. [68]
The western Superior Craton is formed by different terranes stitching with each other continuously during the Neoarchean period. [39] [69] [70] [71] Such a progressive assembly can be explained by five discrete orogenies (mountain-building processes). They are, from the oldest event to the youngest event, the Northern Superior Orogeny, the Uchian Orogeny, the Central Superior Orogeny, the Shebandowanian Orogeny and the Minnesotan Orogeny. [71] These events show that the timeline of accretions starts from the north with a southward assembling direction. [68]
For these accretions, the North Caribou Terrane acted as the accretion nuclei onto which other terranes dock on its northern and southern side.
Before 2720 Ma, there were many pieces of microcontinent fragments which E-W trending conduit-like ocean crusts (with unknown extent) separates them. [70] During 2720 Ma, active subduction along the Northern Superior Superterrane and the North Caribou Terrane caused the southward drifting of the Northern Superior Superterrane. Over time, it united the North Caribou Superterrane and confined the Oxford-Stull domain, which contains rock assemblages related to the continental margin and oceanic crust. [70] [71] The combination of the Northern Superior Superterrane and the North Caribou Superterrane by subduction marked the initiation of the Superior Craton formation. The southward movement of the Northern Superior Superterrane to the North Caribou Superterrane driven by subduction activity is evident by a) arc-related magmatism in Oxford-Stull domain during 2775-2733 Ma; [71] b) the south-over-north shearing zone at the contact between the two terranes. [72] The suture zone of the subduction is inferred to be the margin of the North Kenyon Fault. [71] The docking of the Northern Superior Superterrane is evident by the >3.5 Ga detrital zircons found in synorogenic (meaning that it forms during an orogenic event) sedimentary rocks aged <2.711 Ga. [71] The docking also initiated the eruption of shoshonitic volcanic rocks during 2710 Ma and the regional shortening. The regional shortening had undergone folding and foliation to form right-lateral, NW-trending shear zones. [70] [71]
During this period, the Winnipeg River Terrane at the south docked northward onto the North Caribou Terrane. The two terranes then sutured to form the English River belt, which was no earlier than <2705 Ma. [71]
During the orogeny, at the south-central North Caribou Superterrane, rocks were deformed thoroughly (from 2718 to 2712 Ma). After the deformation, plutons were emplaced in the area after the tectonic movements and cooled by about 2700 Ma. Following the cooling of the pluton was the swift burial and melting of the rocks in the English River belt and Winnipeg River Terrane, as well as the overthrusting of the North Caribou Superterrane onto the English River Basin in a southward direction. [71] Arc-related magmatic activities sustained in other areas of the southern North Caribou Superterrane margin at <2710 Ma. What was following is the deformation penetrative in both eastern (occurred at 2714-2702 Ma) and western (occurred at <2704 Ma) margins, followed by ductile-brittle faults. [70] [71]
The Central Orogeny is significant as it involves the accretion of the younger Western Wabigoon terrane to the southwestern margin of the Winnipeg River Terrane. [71]
Two types of models were proposed to illustrate the process accretion with distinctive subduction polarity: Sanborn-Barrie and Skulski (2006) [73] suggested that the accretion was achieved by the northeastward subduction of the Western Wabigoon Terrane underneath the Winnipeg River Terrane. This model is supported by evidence like the formation of the tonalitic and pyroclastic rocks in 2715-2700Ma and the deformation style of the Warclub turbidite assemblage which infers the over-riding of Winnipeg River Terrane on Western Wabigoon Terrane. [71]
Another type of Models was suggested by Davis and Smith (1991), [74] Percival et al. (2004a) [75] and Melnyk et al. (2006), [29] which suggested an opposite direction of subduction (Southwestward). These models are supported by the ductile rock textures in the lower plate of the Winnipeg River Terrane and the open folds in the Western Wabigoon Terrane, implying the overriding role of Western Wabigoon Terrane instead of Winnipeg River Terrane shown in the previous model. [71]
Shebandowanian orogeny marks the accretion of the Wawa-Abitibi terrane to the composite Superior superterrane at the southern margin of the Wabigoon terranes. [1]
The northward direction of the subduction is evident due to the ceased arc magmatism in Winnipeg River superterrane at about 2695 Ma. Apart from the ceased magmatism, the sanukitoid plutons formed in the area during 2695-2685 Ma (which inferred the breakoff of a subduction slab) also indicated the subduction towards the north. After the subduction, the two terranes were sutured under the Quetico belt. This also trapped the clastic sediments fluxing into the belt, marking its transition from an accretionary wedge to a foreland basin. [71] At the northern Wawa-Abitibi terrane, researchers identified two events of deformation occurred during the orogeny. The first one (D1 deformation event) is the intra-arc deformation accompanied by calc-alkaline magmatism during 2695 Ma. The second one (D2 deformation event) is the transpressive deformation at the margin between the Wawa-Abitibi Terrane and the Wabigoon terranes during 2685-2680 Ma. [71]
As the last significant accretion event, The Minnesotan Orogeny is associated with the accretion of the oceanic Minnesota River Valley Terrane and the composite Superior Craton. Subduction between the two terranes drove the Minnesota River Valley Terrane northward to meet the gigantic craton, which the two terranes sutured along the Great Lake tectonic zone. [71]
The northward direction of the subduction is proven by the peraluminous granitoid magmatism in the southern margin of the Abitibi terrane, as well as the isotopic signature of the ancient crust underneath it. [71]
The Minnesotan orogeny accounts for most of the deformation events in the Wawa-Abitibi Terrane and Minnesota River Valley Terrane. Research in the past regarded the Minnesota River Valley Terrane as a stiff crust with higher resistance relative to the weaker zones between the Minnesota River Valley Terrane and the Wawa-Abitibi Terrane, like a rigid "jaw" juxtaposing a weak zone in the "vice" models suggested by Ellis et al. (1998). [76] However, the study of seismic reflection images by Percival et al. [71] reveals that Minnesota River Valley Terrane positions at the bottom of a thrust sequence, providing evidence that it is an oceanic slab. [71]
| Time | Event | Description |
|---|---|---|
| 2720 Ma | Northern Superior Orogeny | Northern Superior Superterrane moves southward to dock onto the North Caribou Terrane. [70] [71] |
| 2700 Ma | Uchian Orogeny | Winnipeg River Terrane docked northward onto the North Caribou Terrane. [71] |
| 2720-2700 Ma | Central Superior Orogeny | Sanborn-Barrie and Skulski (2006): [73] Western Wabigoon Terrane docked northeastward to the Winnipeg River Terrane. Davis and Smith (1991), [74] Percival et al. (2004a) [75] and Melnyk et al. (2006): [29] The young craton moved southwestward to fuse with the Western Wabigoon Terrane. |
| 2690 Ma | Shebandowanian Orogeny | The Wawa-Abitibi terrane moved northward to collide with the growing craton. [1] |
| 2680 Ma | Minnesotan Orogeny | Minnesotan River Valley Terrane moved northward to collide with the pre-mature craton. [71] |
The correlations of different building processes of the NE Superior Craton remains sophisticated. Still, there are two general understandings to unveil the relationships among the overlapping magmatic and metamorphic events.
The first one is suggested by Percival and Skulski (2000). [5] It is a collisional model which at 2700 Ma, the Rivière terrane from the east collided with the Hudson Bay terrane located at the west side. This collision leads to the high-grade metamorphism followed by a regional folding event. Apart from this, the model relates the collision with the Uchian orogeny concurrently happening at the south and the west. [71]
The second one is suggested by Bédard (2003) [77] and Bédard et al. (2003). [78] This model puts emphasis on the role of magmatic diapirism in the linear structure and metamorphism of the NE superior craton, implying an active anorogenic magmatism during the accretion of the southern Superior Craton.
The Isua Greenstone Belt is an Archean greenstone belt in southwestern Greenland, aged between 3.7 and 3.8 billion years. The belt contains variably metamorphosed mafic volcanic and sedimentary rocks, and is the largest exposure of Eoarchaean supracrustal rocks on Earth. Due to its age and low metamorphic grade relative to many Eoarchaean rocks, the Isua Greenstone Belt has become a focus for investigations on the emergence of life and the style of tectonics that operated on the early Earth.
The Slave Craton is an Archaean craton in the north-western Canadian Shield, in Northwest Territories and Nunavut. The Slave Craton includes the 4.03 Ga-old Acasta Gneiss which is one of the oldest dated rocks on Earth. Covering about 300,000 km2 (120,000 sq mi), it is a relatively small but well-exposed craton dominated by ~2.73–2.63 Ga greenstones and turbidite sequences and ~2.72–2.58 Ga plutonic rocks, with large parts of the craton underlain by older gneiss and granitoid units. The Slave Craton is one of the blocks that compose the Precambrian core of North America, also known as the palaeocontinent Laurentia.
The Trans-Hudson orogeny or Trans-Hudsonian orogeny was the major mountain building event (orogeny) that formed the Precambrian Canadian Shield and the North American Craton, forging the initial North American continent. It gave rise to the Trans-Hudson orogen (THO), or Trans-Hudson Orogen Transect (THOT), which is the largest Paleoproterozoic orogenic belt in the world. It consists of a network of belts that were formed by Proterozoic crustal accretion and the collision of pre-existing Archean continents. The event occurred 2.0–1.8 billion years ago.
The Wyoming Craton is a craton in the west-central United States and western Canada – more specifically, in Montana, Wyoming, southern Alberta, southern Saskatchewan, and parts of northern Utah. Also called the Wyoming Province, it is the initial core of the continental crust of North America.
Laurentia or the North American Craton is a large continental craton that forms the ancient geological core of North America. Many times in its past, Laurentia has been a separate continent, as it is now in the form of North America, although originally it also included the cratonic areas of Greenland and also the northwestern part of Scotland, known as the Hebridean Terrane. During other times in its past, Laurentia has been part of larger continents and supercontinents and itself consists of many smaller terranes assembled on a network of Early Proterozoic orogenic belts. Small microcontinents and oceanic islands collided with and sutured onto the ever-growing Laurentia, and together formed the stable Precambrian craton seen today.
The Algoman orogeny, known as the Kenoran orogeny in Canada, was an episode of mountain-building (orogeny) during the Late Archean Eon that involved repeated episodes of continental collisions, compressions and subductions. The Superior province and the Minnesota River Valley terrane collided about 2,700 to 2,500 million years ago. The collision folded the Earth's crust and produced enough heat and pressure to metamorphose the rock. Blocks were added to the Superior province along a 1,200 km (750 mi) boundary that stretches from present-day eastern South Dakota into the Lake Huron area. The Algoman orogeny brought the Archean Eon to a close, about 2,500 million years ago; it lasted less than 100 million years and marks a major change in the development of the Earth's crust.
The Great Lakes tectonic zone (GLTZ) is bounded by South Dakota at its tip and heads northeast to south of Duluth, Minnesota, then heads east through northern Wisconsin, Marquette, Michigan, and then trends more northeasterly to skim the northernmost shores of lakes.
The Wopmay orogen is a Paleoproterozoic orogenic belt in northern Canada which formed during the collision between the Hottah terrane, a continental magmatic arc, and the Archean Slave Craton at about 1.88 Ga. The collision lead to the short-lived Calderian orogeny. The formation was named for Wilfrid Reid "Wop" May, OBE, DFC, a Canadian flying ace in the First World War and a leading post-war aviator.
The Grouse Creek block is a Precambrian basement province of 2.45 to 2.70 billion year old orthogneisses. The Grouse Creek block is one of several Proterozoic and Archean accreted terranes that lie to the north and west of the Wyoming craton, including the Farmington Canyon Complex, the Selway terrane, the Medicine Hat block and the Priest River complex. Together, these terranes comprise part of the basement rock of the North American continent and have been critical to studies of crustal accretion in the Precambrian. Ongoing study of the Grouse Creek block will contribute to understanding the paleogeography of the Wyoming craton prior to its incorporation into the supercontinent Laurentia approximately 1.86 billion years ago. The name was proposed by David Foster and others.
The Eastern Pilbara Craton is the eastern portion of the Pilbara Craton located in Western Australia. This region contains variably metamorphosed mafic and ultramafic greenstone belt rocks, intrusive granitic dome structures, and volcanic sedimentary rocks. These greenstone belts worldwide are thought to be the remnants of ancient volcanic belts, and are subject to much debate in today's scientific community. Areas such as Isua and Barberton which have similar lithologies and ages as Pilbara have been argued to be subduction accretion arcs, while others suggest that they are the result of vertical tectonics. This debate is crucial to investigating when/how plate tectonics began on Earth. The Pilbara Craton along with the Kaapvaal Craton are the only remaining areas of the Earth with pristine 3.6–2.5 Ga crust. The extremely old and rare nature of this crustal region makes it a valuable resource in the understanding of the evolution of the Archean Earth.
The Svecofennian orogeny is a series of related orogenies that resulted in the formation of much of the continental crust in what is today Sweden and Finland plus some minor parts of Russia. The orogenies lasted from about 2000 to 1800 million years ago during the Paleoproterozoic Era. The resulting orogen is known as the Svecofennian orogen or Svecofennides. To the west and southwest the Svecofennian orogen limits with the generally younger Transscandinavian Igneous Belt. It is assumed that the westernmost fringes of the Svecofennian orogen have been reworked by the Sveconorwegian orogeny just as the western parts of the Transscandinavian Igneous Belt has. The Svecofennian orogeny involved the accretion of numerous island arcs in such manner that the pre-existing craton grew with this new material from what is today northeast to the southwest. The accretion of the island arcs was also related to two other processes that occurred in the same period; the formation of magma that then cooled to form igneous rocks and the metamorphism of rocks.
Eoarchean geology is the study of the oldest preserved crustal fragments of Earth during the Eoarchean era from 4 to 3.6 billion years ago. Major well-preserved rock units dated Eoarchean are known from three localities, the Isua Greenstone Belt in Southwest Greenland, the Acasta Gneiss in the Slave Craton in Canada, and the Nuvvuagittuq Greenstone Belt in the eastern coast of Hudson Bay in Quebec. From the dating of rocks in these three regions scientists suggest that plate tectonics could go back as early as Eoarchean.
Archean felsic volcanic rocks are felsic volcanic rocks that were formed in the Archean Eon. The term "felsic" means that the rocks have silica content of 62–78%. Given that the Earth formed at ~4.5 billion year ago, Archean felsic volcanic rocks provide clues on the Earth's first volcanic activities on the Earth's surface started 500 million years after the Earth's formation.
The Grenville Province is a tectonically complex region, in Eastern Canada, that contains many different aged accreted terranes from various origins. It exists southeast of the Grenville Front and extends from Labrador southwestern to Lake Huron. It is bounded by the St. Lawrence River/Seaway to the southeast.
The geology of the Northwest Territories has been mapped in different quadrangles by the Canadian government. The region has some of the oldest rocks in the world and among the oldest in North America, formed from several sections of stable craton continental crust, including the Slave Craton, Rae Craton and Hearne Craton. These rocks form the Archean and Proterozoic Precambrian basement rock of the region and are the subject of extensive research to understand continental crust and tectonic conditions on the early Earth.
The Eastern Block of the North China Craton is one of the Earth's oldest pieces of continent. It is separated from the Western Block by the Trans-North China Orogen. It is situated in northeastern China and North Korea. The Block contains rock exposures older than 2.5 billion years. It serves as an ideal place to study how the crust was formed in the past and the related tectonic settings.
The South China Craton or South China Block is one of the Precambrian continental blocks in China. It is traditionally divided into the Yangtze Block in the NW and the Cathaysia Block in the SE. The Jiangshan–Shaoxing Fault represents the suture boundary between the two sub-blocks. Recent study suggests that the South China Block possibly has one more sub-block which is named the Tolo Terrane. The oldest rocks in the South China Block occur within the Kongling Complex, which yields zircon U–Pb ages of 3.3–2.9 Ga.
The Western Block of the North China Craton is an ancient micro-continental block mainly composed of Neoarchean and Paleoproterozoic rock basement, with some parts overlain by Cambrian to Cenozoic volcanic and sedimentary rocks. It is one of two sub-blocks within the North China Craton, located in east-central China. The boundaries of the Western Block are slightly different among distinct models, but the shapes and areas are similar. There is a broad consensus that the Western Block covers a large part of the east-central China.
The Dharwar Craton is an Archean continental crust craton formed between 3.6-2.5 billion years ago (Ga), which is located in southern India and considered as the oldest part of the Indian peninsula.
The geology of the Kimberley, a region of Western Australia, is a rock record of early Proterozoic plate collision, orogeny and suturing between the Kimberley Craton and the Northern Australia Craton, followed by sedimentary basin formation from Proterozoic to Phanerozoic.
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