Journal articles: 'Craton margins'

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Wang, Xu, Peimin Zhu, Timothy M. Kusky, Na Zhao, Xiaoyong Li, and Zhensheng Wang. "Dynamic cause of marginal lithospheric thinning and implications for craton destruction: a comparison of the North China, Superior, and Yilgarn cratons." Canadian Journal of Earth Sciences 53, no. 11 (November 2016): 1121–41. http://dx.doi.org/10.1139/cjes-2015-0110.

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We present a comparative tectonic analysis of the North China Craton (NCC), which has lost parts of its root, with the Yilgarn and Superior cratons, which preserve their roots. We compare the geophysical structure and tectonic histories of these cratons to search for reasons why some cratons lose their roots, while others retain them. Based on the comparison and analysis of geological, geophysical, and geochemical data, it is clear that the lithospheric thinning beneath craton margins is a common phenomenon, which may be caused by convergence between plates. However, craton destruction is not always accompanied by lithospheric thinning, except for cratons that suffered subduction and collision from multiple sides. The Western Block (also known as the Ordos Block) of the NCC, Yilgarn and Superior cratons have not experienced craton destruction; the common ground among them is that they are surrounded by weak zones (e.g., mobile belts or orogens) that sheltered the cratons from deformation, which contributes greatly to the long-term stability of the craton. Subduction polarity controlled the water released by the subducting plate, and if subducting plates dip underneath the craton, they release water that hydroweakens the overlying mantle, and makes it easy for delamination or sub-continental lithospheric mantle erosion to take place in the interior of the craton. Thus, subduction polarity during convergence events is an important element in determing whether a craton retains or loses its root.

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Dalziel, Ian W. D. "Antarctica and supercontinental evolution: clues and puzzles." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 104, no. 1 (March 2013): 3–16. http://dx.doi.org/10.1017/s1755691012000096.

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ABSTRACTAntarctica has been known as the “keypiece” of the Gondwana supercontinent since publication of Du Toit's 1937 classic bookOur Wandering Continents. It is also important to reconstruction of the early Neoproterozoic supercontinent Rodinia. Laurentia, with its circumferential late Precambrian rifted margins, can be regarded as the ‘keypiece’ of Rodinia. TheSouthwest US–EastAntarctica (SWEAT) hypothesis suggested former juxtaposition of the Pacific margins of Laurentia and East Antarctica. Several new lines of evidence support this hypothesis in a revised form, but must be reconciled with opening of the Pacific Ocean basin predating amalgamation, not only of Gondwana, but even of today's East Antarctic craton. The sequence of events is envisaged to have been: (1) formation prior to 1·6 Ga of a craton, including Laurentia and the Mawson craton, that extended from South Australia along the present Transantarctic margin to the Shackleton Range; (2) suturing of southernmost Laurentia to the Kalahari craton along the Grenville, Namaqua–Natal–Maud orogenic belt ca. 1·0 Ga; (3) rifting of the East Antarctic margin (Mawson craton) from western Laurentia ca. 0·7 Ga; (4) pan-African suturing of the Mawson craton to southernmost Laurentia as Gondwana amalgamated, forming the ephemeral Pannotia supercontinent; and (5) end-Precambrian separation of Laurentia as Iapetus opened.

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Pearson, N. J., S. Y. O'Reilly, and W. L. Griffin. "The crust-mantle boundary beneath cratons and craton margins: a transect across the south-west margin of the Kaapvaal craton." Lithos 36, no. 3-4 (December 1995): 257–87. http://dx.doi.org/10.1016/0024-4937(95)00021-6.

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Hoffman, Paul F. "The Origin of Laurentia: Rae Craton as the Backstop for Proto-Laurentian Amalgamation by Slab Suction." Geoscience Canada 41, no. 3 (August 29, 2014): 313. http://dx.doi.org/10.12789/geocanj.2014.41.049.

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Proto-Laurentia (i.e. pre-Grenvillian Laurentia) is an aggregate of six or more formerly independent Archean cratons that amalgamated convulsively in geons 19 and 18 (Orosirian Period), along with non-uniformly distributed areas of juvenile Paleoproterozoic crust. Subduction polarities and collision ages have been provisionally inferred between the major cratons (and some minor ones), most recently between the Rae and Hearne cratons. The oldest Orosirian collisions bound the Rae craton: 1.97 Ga (Taltson-Thelon orogen) in the west, and 1.92 Ga (Snowbird orogen) in the southeast. All other Orosirian collision ages in proto-Laurentia are < 1.88 Ga. The Rae craton was the upper plate during (asynchronous) plate convergence at its western and, tentatively, southeastern margins. Subsequent plate convergence in the Wopmay and Trans-Hudson orogens was complex, with the Rae craton embedded in the lower plate prior to the first accretion events (Calderian, Reindeer and Foxe orogenies), but in the upper plate during major subsequent convergence and terminal collisions, giving rise to the Great Bear and Cumberland magmatic arcs, respectively. The ‘orthoversion’ theory of supercontinental succession postulates that supercontinents amalgamate over geoidal lows within a meridional girdle of mantle downwellings, orthogonal to the lingering superswell at the site of the former supercontinent. If the downwelling nodes develop through positive feedback from the descent of cold oceanic slabs, then viscous traction should contribute to drawing the cratons together over the downwelling node. Viewed in this way, the Rae craton was the first to settle over the downwelling node and became the backstop for the other cratons that were drawn towards it by subduction. It was, literally, the origin of Laurentia. Whether the Rae craton was also the origin of Nuna, the hypothetical cogenetic supercontinent, depends on ages and subduction polarities of Orosirian sutures beyond proto-Laurentia.SOMMAIRELa proto-Laurentie (c.-à-d. la Laurentie pré-grenvillienne) est un agrégat d’au moins six cratons archéens indépendants qui se sont amalgamés convulsivement durant les géons 19 et 18 (Orosirien), le long de zones de croûtes juvéniles paléoprotérozoïques réparties de manière hétérogène. Les polarités de subduction et les âges de collision entre les grands cratons (et d’autres moins grands) ont été provisoirement déduits, le plus récemment entre le craton de Rae et le craton de Hearne. Les plus anciennes collisions orosiriennes ont soudé le craton de Rae : 1,97 Ga (orogène de Taltson-Thelon) dans l’ouest, et 1,92 Ga (orogène de Snowbird) dans le sud-est. Tous les autres âges de collision en proto-Laurentie sont inférieurs à 1,88 Ga. Le craton de Rae constituait la plaque supérieure durant la convergence de plaque (asynchrone) à sa marge ouest, et peut-être aussi à ses marges sud-est. La convergence de plaque subséquente dans les orogènes de Wopmay et Trans-Hudson a été complexe, le craton de Rae étant encastré dans la plaque inférieure avant les premiers événements d’accrétion (orogènes caldérienne, de Reindeer et de Fox), puis dans la plaque supérieure durant la grande convergence subséquente et les collisions terminales, ce qui a créé les arcs magmatiques de Great Bear et de Cumberland respectivement. La théorie de « l’orthoversion » de la succession des supercontinents présuppose que les supercontinents s’amalgament au-dessus de creux géoïdaux en deça d’une gaine méridienne de convections mantéliques descendantes, à angle droit d’un super-renflement persistant au site d’un ancien supercontinent. Si le nœud de convection descendante s’établit par rétroaction positive de la descente de plaques océaniques froides, la traction visqueuse devrait contribuer à entraîner les cratons ensembles au-dessus du nœud de convection descendante. Vu de cette façon, le craton de Rae a été le premier à s’établir au-dessus du nœud de convection descendante, ce qui en a fait la butée des autres cratons entraînés par la subduction. Littéralement, telle a été l’origine de la Laurentie. Quant à savoir si c’est le craton de Rae qui a été à l’origine de Nuna, cet hypothétique surpercontinent cogénétique, cela dépend des âges et des polarités de subduction des sutures orosiriennes au-delà de la proto-Laurentie.

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Likhanov, Igor I. "Provenance, Age, and Tectonic Settings of Rock Complexes (Transangarian Yenisey Ridge, East Siberia): Geochemical and Geochronological Evidence." Geosciences 12, no. 11 (October 29, 2022): 402. http://dx.doi.org/10.3390/geosciences12110402.

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The tectonic evolution of the Siberian Cratonic margins offers important clues for global paleogeographic reconstructions, particularly with regard to the complex geological history of Central Asia and Precambrian supercontinents Columbia/Nuna and Rodinia and its subsequent breakup with the opening of the Paleo-Asian Ocean. Here, we present an overview of geochemical, petrological, and geochronological data from a suite of various rocks to clarify the age, tectonic settings, and nature of their protolith, with an emphasis on understanding the tectonic history of the Yenisey Ridge fold-and-thrust belt at the western margin of the Siberian Craton. These pre-Grenville, Grenville, and post-Grenville episodes of regional crustal evolution are correlated with the synchronous successions and similar style of rocks along the Arctic margin of Nuna-Columbia and Rodinia and support the possible spatial proximity of Siberia and North Atlantic cratons (Laurentia and Baltica) over a long period ~1.4-0.55 Ga.

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Ernst, Richard, and Wouter Bleeker. "Large igneous provinces (LIPs), giant dyke swarms, and mantle plumes: significance for breakup events within Canada and adjacent regions from 2.5 Ga to the PresentThis article is one of a selection of papers published in this Special Issue on the the theme Lithoprobe—parameters, processes, and the evolution of a continent.Lithoprobe Contribution 1482. Geological Survey of Canada Contribution 20100072." Canadian Journal of Earth Sciences 47, no. 5 (May 2010): 695–739. http://dx.doi.org/10.1139/e10-025.

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Large igneous provinces (LIPs) are high volume, short duration pulses of intraplate magmatism consisting mainly of flood basalts and their associated plumbing system, but also may include silicic components and carbonatites. Many LIPs have an associated radiating diabase dyke swarm, which typically converges on a cratonic margin, identifies a mantle plume centre, and is linked to breakup or attempted breakup to form that cratonic margin. We hypothesize that every major breakup margin in Canada can be associated with a LIP, and we attempt to identify this LIP. To this end, we focus mainly on high-precision age determinations and the distribution of diabase dyke swarms, which are uniquely valued for preserving the record of magmatic events. The analysis extends from the Phanerozoic to the Neoarchean, but our most complete information is for the Superior craton. There, events at 2.50–2.45, 2.22–2.17, and 2.12–2.08 Ga (LIP and plume) are linked with rifting and breakup or attempted breakup of the south-southeastern, northeastern, and southern margins, respectively. Events at 2.00–1.97 Ga are probably linked with the northern margin (Ungava promontory), while the Circum-Superior event at ca. 1.88 Ga is linked to the north to northwestern margins during a time of Manikewan Ocean closure. Similar linkages for other cratons of North America improve understanding of the breakup history to help identify which blocks were nearest neighbours to Canadian crustal blocks in Precambrian supercontinents. Such interpretations provide a framework for interpreting other geological features of these margins to further test models for the timing and location of breakup.

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Manighetti, Isabelle, André Michard, and Omar Saddiqi. "The West African Craton and its margins. Foreword." Comptes Rendus Geoscience 350, no. 6 (September 2018): 233–35. http://dx.doi.org/10.1016/j.crte.2018.07.001.

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Hoffman, Paul F., Samuel A. Bowring, Robert Buchwaldt, and Robert S. Hildebrand. "Birthdate for the Coronation paleocean: age of initial rifting in Wopmay orogen, CanadaThis article is one of a series of papers published in this Special Issue on the theme of Geochronology in honour of Tom Krogh." Canadian Journal of Earth Sciences 48, no. 2 (February 2011): 281–93. http://dx.doi.org/10.1139/e10-038.

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The 1.9 Ga Coronation “geosyncline” to the west of Slave craton was among the first Precambrian continental margins to be identified, but its duration as a passive margin has long been uncertain. We report a new U–Pb (isotope dilution – thermal ionization mass spectrometry (ID–TIMS)) 207Pb/206Pb date of 2014.32 ± 0.89 Ma for zircons from a felsic pyroclastic rock at the top of the Vaillant basalt, which underlies the passive margin sequence (Epworth Group) at the allochthonous continental slope. A sandstone tongue within the basalt yields Paleoproterozoic (mostly synvolcanic) and Mesoarchean detrital zircon dates, of which the latter are compatible with derivation from the Slave craton. In contrast, detrital zircon grains from the Zephyr arkose in the accreted Hottah terrane have Paleoproterozoic and Neoarchean dates. The latter cluster tightly at 2576 Ma, indistinguishable from igneous zircon dates reported here from the Badlands granite, which is faulted against the Vaillant basalt and underlying Drill arkose. We interpret these data to indicate that Badlands granite belongs to the hanging wall of the collisional geosuture between Hottah terrane and the Slave margin, represented by the Drill–Vaillant rift assemblage. If 2014.32 ± 0.89 Ma dates the rift-to-drift transition and 1882.50 ± 0.95 Ma (revised from 1882 ± 4 Ma) the arrival of the passive margin at the trench bordering the Hottah terrane, the duration of the Coronation passive margin was ∼132 million years, close to the mean age of extinct Phanerozoic passive margins of ∼134 million years (see Bradley 2008).

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Currie, Claire A., and Jolante van Wijk. "How craton margins are preserved: Insights from geodynamic models." Journal of Geodynamics 100 (October 2016): 144–58. http://dx.doi.org/10.1016/j.jog.2016.03.015.

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Gorczyk, W., D. R. Mole, and S. J. Barnes. "Plume-lithosphere interaction at craton margins throughout Earth history." Tectonophysics 746 (October 2018): 678–94. http://dx.doi.org/10.1016/j.tecto.2017.04.002.

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PENG, PENG, MINGGUO ZHAI, JINGHUI GUO, HUAFENG ZHANG, and YANBIN ZHANG. "Petrogenesis of Triassic post-collisional syenite plutons in the Sino-Korean craton: an example from North Korea." Geological Magazine 145, no. 5 (June 10, 2008): 637–47. http://dx.doi.org/10.1017/s0016756808005037.

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AbstractMore than ten Triassic syenite plutons are revealed to be distributed in North Korea along the boundary to South Korea. The Tokdal Complex is one of these but is unique in its incorporation of early pyroxenite cumulate in the clinopyroxene/amphibole/biotite/nepheline-bearing syenite main body. A SHRIMP U–Pb zircon age of 224 ± 4 Ma was obtained from a biotite syenite sample. Clinopyroxene in pyroxenite is zoned, with either phlogopite and apatite inclusion or ilmenite and magnetite exsolution, and may have resulted from crystallization at high pressure in an active continental margin arc environment followed by ascent and decompression. The pyroxenite and syenite are enriched in light REE and LILE, but strongly depleted in HFSE, with 87Sr/86Srt values of ~0.7115 and ϵNdt values of −14 to −20 (t = 224 Ma). The Tokdal Complex could have originated from an enriched lithospheric mantle and undergone assimilation of juvenile materials during differentiation. It indicates an extension of post-collisional magmatism in the Sino-Korean craton. This complex along with many other Triassic plutons in the Sino-Korean craton together constitute three syenite belts along the northern, southern and eastern margins of the craton, possibly resulting in its final configuration in eastern Asia.

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Schmitt, Renata da Silva, Rudolph Trouw, William Randall Van Schmus, Richard Armstrong, and Natasha S. Gomes Stanton. "The tectonic significance of the Cabo Frio Tectonic Domain in the SE Brazilian margin: a Paleoproterozoic through Cretaceous saga of a reworked continental margin." Brazilian Journal of Geology 46, suppl 1 (June 2016): 37–66. http://dx.doi.org/10.1590/2317-4889201620150025.

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ABSTRACT: The Cabo Frio Tectonic Domain is composed of a Paleoproterozoic basement tectonically interleaved with Neoproterozoic supracrustal rocks (Buzios-Palmital successions). It is in contact with the Neoproterozoic-Cambrian Ribeira Orogen along the SE Brazilian coast. The basement was part of at least three continental margins: (a) 1.97 Ga; (b) 0.59 - 0.53 Ga; (c) 0.14 Ga to today. It consists of continental magmatic arc rocks of 1.99 to 1.94 Ga. Zircon cores show a 2.5 - 2.6 Ga inheritance from the ancient margin of the Congo Craton. During the Ediacaran, this domain was thinned and intruded by tholeiitic mafic dykes during the development of an oceanic basin at ca. 0.59 Ma. After the tectonic inversion, these basin deposits reached high P-T metamorphic conditions, by subduction of the oceanic lithosphere, and were later exhumed as nappes over the basement. The Cabo Frio Tectonic Domain collided with the arc domain of the Ribeira Orogen at ca. 0.54 Ga. It is not an exotic block, but the eastern transition between this orogen and the Congo Craton. Almost 400 m.y. later, the South Atlantic rift zone followed roughly this suture, not coincidently. It shows how the Cabo Frio Tectonic Domain was reactivated as a continental margin in successive extensional and convergent events through geological time.

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Eakin, Caroline. "Seismicity, Minerals, and Craton margins: The Lake Eyre Basin Seismic Deployment." ASEG Extended Abstracts 2019, no. 1 (November 11, 2019): 1–2. http://dx.doi.org/10.1080/22020586.2019.12072989.

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Griffin, W. "The evolution of lithospheric mantle beneath the Kalahari Craton and its margins." Lithos 71, no. 2-4 (December 2003): 215–41. http://dx.doi.org/10.1016/j.lithos.2003.07.006.

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Siegesmund, Siegfried, Miguel Basei, and Pedro Oyhantçabal. "Multi-accretional tectonics at the Rio de la Plata Craton margins: preface." International Journal of Earth Sciences 100, no. 2-3 (November 19, 2010): 197–200. http://dx.doi.org/10.1007/s00531-010-0616-0.

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Ashton, K. E., L. M. Heaman, J. F. Lewry, R. P. Hartlaub, and R. Shi. "Age and origin of the Jan Lake Complex: a glimpse at the buried Archean craton of the Trans-Hudson Orogen." Canadian Journal of Earth Sciences 36, no. 2 (February 1, 1999): 185–208. http://dx.doi.org/10.1139/e98-038.

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The largely buried Sask Craton is a continental fragment or microcontinent that collided with and underthrust the Paleoproterozoic Flin Flon - Glennie protocontinent along the Pelican Décollement Zone at 1840-1830 Ma. Rocks of the Sask Craton are exposed in three tectonic windows. Those of the Pelican Window have been named the Jan Lake Complex and comprise [Formula: see text] 2960 Ma arc-derived leucocratic orthogneisses, migmatitic paragneisses, and a tholeiitic, within-plate igneous suite comprising 2488 Ma dioritic to gabbroic rocks and 2450 Ma enderbitic and charnockitic rocks including the Sahli Granite. Ages of ca. 2450 Ma are also common from the other two tectonic windows to the Sask Craton, suggesting that emplacement of the igneous suite was widespread and perhaps part of the coeval Matachewan Igneous Event. The absence of rocks in the [Formula: see text] 2960 and ca. 2450 Ma age ranges on both the adjacent Superior and Rae-Hearne cratonic margins makes it improbable that the Sask Craton was derived by simple fragmentation without large-scale tectonic transport. The overthrust Paleoproterozoic rocks represent a high-grade northwestern extension of the Flin Flon volcanic belt and include 1856 Ma leucotonalite and 1843 Ma quartz monzodiorite. An 1830 Ma suite of homogeneous, calc-alkaline enderbitic rocks, which intrude Burntwood semipelitic migmatites throughout the Kisseynew Domain, has also been emplaced in mylonites of the Pelican Décollement Zone. Zircon and monazite ages in the 1812-1803 Ma range record a high-grade metamorphic event that resulted from collision between the Sask Craton and Flin Flon - Glennie Complex.

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Bostock, M. G., and J. F. Cassidy. "Upper mantle stratigraphy beneath the southern Slave craton." Canadian Journal of Earth Sciences 34, no. 5 (May 1, 1997): 577–86. http://dx.doi.org/10.1139/e17-046.

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A large teleseismic data set comprising 724 broadband, three-component P-wave seismograms has been compiled for the southern Slave craton with the objective of characterizing underlying mantle stratigraphy. Coherent P to S wave conversions are identified by simultaneously deconvolving seismograms as functions of epicentral distance and along theoretical moveout curves corresponding to possible mantle phases. Clear PDs conversions are observed from the 410 and 660 km discontinuities at times that are only slightly faster than those predicted from the IASP91 model, and over 1.0 s slower than corresponding times observed at other stations on the Canadian Shield and the south African Kaapvaal craton. The PDs times show very little azimuthal variation, implying an absence of major lateral velocity variations in the lithospheric mantle underlying the Slave craton, and adjacent Wopmay orogen and Taltson magmatic zone. Considered in light of other geophysical and geological evidence, these results suggest that the root underlying the Slave province has been modified along its margins and may remain intact only toward a central core. Another important result involves the observation of a PDs conversion from a negative velocity contrast interface at approximately 360 km depth. It and a similar phase, observed on the Kaapvaal craton, would appear not to be directly related to tectospheric structure, but may originate at the top of a layer containing a dense silicate partial melt just above the mantle transition zone.

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Wang, Junpeng, Xiawen Li, Wenbin Ning, Timothy Kusky, Lu Wang, Ali Polat, and Hao Deng. "Geology of a Neoarchean suture: Evidence from the Zunhua ophiolitic mélange of the Eastern Hebei Province, North China Craton." GSA Bulletin 131, no. 11-12 (April 24, 2019): 1943–64. http://dx.doi.org/10.1130/b35138.1.

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Abstract Mélanges characterize Phanerozoic convergent plate boundaries, but have rarely been reported from Archean orogens. In this paper, we document a Neoarchean ophiolitic mélange in the Eastern Hebei Province of the North China Craton. The Zunhua ophiolitic mélange is composed of a structural mixture of metapelites, ortho- and para-gneisses, and magnetite-quartzite mixed with exotic tectonic mafic blocks of metabasalts, metagabbroic rocks, and metadiabases, along with ultramafic blocks of serpentinized peridotites and podiform chromitites. The Zunhua ophiolitic mélange shows typical “block in matrix” structures. All units of the mélange have been intruded by granitic dikes and quartz veins that clearly cross-cut the foliation of blocks and matrix of the mélange. Laser-ablation–inductively coupled plasma–mass spectrometry zircon U-Pb dating of detrital zircons from the meta-sedimentary mélange matrix and intruding granitic dikes constrains the formation time of the Zunhua mélange to be between 2.52 and 2.46 Ga. Metamorphic rims on zircons from meta-sedimentary mélange matrix have ages of 2467 ± 27 Ma, confirming metamorphism of the mélange occurred at ca. 2.47 Ga. High-precision (scale 1:20 and 1:50) litho-structural mapping, along with detailed structural observations along several transects documents the internal fabrics and kinematics of the mélange, revealing a northwest to southeast directed transportation. The asymmetric structures in the mélange with folding and faulting events in the Zunhua mélange record kinematic information and are similar to the tectonic style of an accretionary wedge. Field relationships and geochemical analysis of various mafic blocks show that these blocks formed in an arc-related subduction tectonic environment. We suggest that the Zunhua mélange marks the suture zone of a Neoarchean arc-continent collisional event in the Central Orogenic Belt of the North China Craton. Combined with our previous studies, we demonstrate that a ca. 2.5 Ga tectonic suture exists between an arc/accretionary prism terrane in the Central Orogenic Belt and the Eastern Block of the North China Craton. We correlate this segment of the suture with other similar zones along strike, for >1000 km, including sections of the ca. 2.5 Ga in Dengfeng greenstone belt in the southern margin of the Central Orogenic Belt, and the ca. 2.5 Ga Zanhuang ophiolitic mélange in the center of the orogen. These relationships demonstrate that tectonic processes in the late Archean included subduction/accretion at convergent margins, and the horizontal movement of plates, in a style similar to modern-day accretionary convergent margins.

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Thomas, Robert J., Christopher Spencer, Alphonce M. Bushi, Nick Baglow, Nelson Boniface, Gerrit de Kock, Matthew S. A. Horstwood, et al. "Geochronology of the central Tanzania Craton and its southern and eastern orogenic margins." Precambrian Research 277 (May 2016): 47–67. http://dx.doi.org/10.1016/j.precamres.2016.02.008.

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Dalziel, Ian W. D. "A global perspective on the Scottish Caledonides." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 91, no. 3-4 (2000): 405–20. http://dx.doi.org/10.1017/s0263593300008269.

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ABSTRACTThe Scottish Caledonides constitute less than 10% of the length of the Caledonian-Appalachian orogen, the rocks of which define one major margin of the Laurentian craton in Neoproterozoic-Palaeozoic times. Scotland was located, however, in a critical position at the tip of a major cratonic promontory bounded by the Caledonian and Appalachian segments of that margin. Isotopic dates from minerals and rocks collected in the Scottish Highlands have been regarded for 40 years as indicating a Neoproterozoic history of compressive orogenesis that is absent in N America and Greenland. They have therefore been taken by some authors to indicate an origin exotic to Laurentia for rocks of the Northern and Grampian Highlands S and E of the Moine thrust belt. An alternative explanation is that the Neoproterozoic rocks in the Scottish Highlands are all related to the two-stage ‘breakout’ of a discrete rift-bounded Laurentian continent from the core of the Rodinian supercontinent, believed to have assembled at the end of the Mesoproterozoic.Traditional reconstructions of the late Neoproterozoic–Early Palaeozoic Earth oppose the proto-Caledonian/Appalachian margin of Laurentia and the W African craton of the newly assembled Gondwanaland. However, consideration of the global inventory of late Precambrian rifted margins, their relation to Grenvillian orogenic belts and of scale, leads to the hypothesis that the conjugate was the proto-Andean margin of S America. Recent recognition that the Cambrian and Lower Ordovician strata of the northwestern Argentine Precordillera and their underlying Grenvillian basement are unquestionably of Laurentian derivation, while not definitive, does point in this direction. If correct, this means that even the presence of Neoproterozoic orogenesis need not imply an exotic origin, as Neoproterozoic orogens are widespread in S America.Traditional models show an Early Ordovician lapetus ocean basin approximately 4500 km wide, but the remarkably synchronous Ordovician collision of arcs and other terranes with the Laurentian and Gondwanan cratons from Argentina to the British Isles, suggests that this premise may be incorrect. The Appalachian–Caledonian orogen may rather have resulted from close and complex tectonic interaction between Laurentia and Gondwana, involving intervening volcanic arcs and other terranes. The interaction may have taken place during a clockwise transit of Laurentia around the proto-Andean margin to its late Caledonian–Scandian collision with Baltica, and the final suturing of Pangaea at the close of the Palaeozoic era. A modern analogue may be the interaction between Australia and Asia, involving intervening volcanic arcs and other terranes of the western Pacific Ocean basin, from ~ 50 Ma through the Present, and into the future.

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Harris, M. J., D. TA Symons, W. H. Blackburn, A. Turek, and D. C. Peck. "Paleomagnetism of the Wintering Lake pluton and the Early Proterozoic tectonic motion of the Superior Boundary Zone, Manitoba." Canadian Journal of Earth Sciences 43, no. 7 (July 1, 2006): 1071–83. http://dx.doi.org/10.1139/e06-015.

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This Lithoprobe-funded paleomagnetic study of the Early Proterozoic Wintering Lake granitoid body supports tectonic models that suggest continental accretion of the Trans-Hudson Orogen with the Superior Craton occurred at ~1822 Ma. Thermal demagnetization data for the granitoid specimens suggest that the magnetic remanence carriers are coarse-grained magnetite or titanomagnetite, and saturation isothermal remanence tests suggest that the magnetite is mostly multidomain. Six of seven paleomagnetic contact tests were negative, indicating that the host rocks have been remagnetized and that the granitoid body may have been partially remagnetized near its margins. Acceptable site mean remanence directions for 20 of 21 granitic sites yield a paleopole at 46.8°N, 102.2°W (with semi-axes of the 95% ellipse of confidence about the paleopole of dp = 11° and dm = 11°). The paleopole fits on the extrapolated apparent polar wander path (APWP) for the Superior craton at ~1822 Ma, which is the interpreted emplacement age of the pluton close to the peak of the Trans-Hudson orogeny. This is the first well-constrained paleomagnetic result from the Superior Province that provides direct evidence from concordant paleopoles for the Early Proterozoic accretion of the orogen to the craton. Further, the paleomagnetic results from the pluton's host rocks, along with other recent results from the Superior Boundary Zone, fill in a gap in the APWP for the craton between ~1780 and ~1720 Ma. The Superior path is now shown to form a hairpin as the craton moves from mid to polar paleolatitudes from ~1880 to ~1830 Ma, suffers a stillstand from ~1830 to ~1770 Ma during the peak of the Trans-Hudson orogeny, returns to mid-paleolatitudes from ~1770 to ~1740 Ma, and then moves on to subequatorial paleolatitudes by ~1720 Ma.

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Saha, Dilip, and Sarbani Patranabis-Deb. "Proterozoic evolution of Eastern Dharwar and Bastar cratons, India – An overview of the intracratonic basins, craton margins and mobile belts." Journal of Asian Earth Sciences 91 (September 2014): 230–51. http://dx.doi.org/10.1016/j.jseaes.2013.09.020.

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Adams, John, and John J. Clague. "Neotectonics and large-scale geomorphology of Canada." Progress in Physical Geography: Earth and Environment 17, no. 2 (June 1993): 248–64. http://dx.doi.org/10.1177/030913339301700209.

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Canada includes active convergent and strike-slip plate boundaries, several major mountain systems, two passive continental margins, and a stable craton. Neotectonic activity, as indicated by earthquake occurrence, is highest along the west coast and lowest in the interior of the country. Correlations between tectonics and physiography are strongest in the west. Here, the landscape bears a strong imprint of convergent and strike-slip plate regimes. Late Mesozoic and early Cenozoic tectonic events established the setting in which the present physiography of western Canada developed, but the landscape acquired its present form much more recently, in Pliocene and Quaternary time. In contrast, the neotectonic imprint in eastern and northern Canada is enigmatic, and although major concentrations of earthquakes in many areas are associated with reactivated, early Phanerozoic structures, there has been only limited late Quaternary faulting. The vast Canadian craton, despite its very low seismicity, is deforming isostatically at a moderate rate due to melting of the Laurentide Ice Sheet thousands of years ago.

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Maslov, A. V., and M. V. Isherskaya. "Riphean sedimentary sequences of the eastern and northeastern margins of the Eastern European craton." Russian Journal of Earth Sciences 4, no. 4 (August 16, 2002): 271–76. http://dx.doi.org/10.2205/2002es000097.

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Yang, Li-Qiang, Jun Deng, David I. Groves, M. Santosh, Wen-Yan He, Nan Li, Liang Zhang, Rui-Rui Zhang, and Hong-Rui Zhang. "Metallogenic ‘factories’ and resultant highly anomalous mineral endowment on the craton margins of China." Geoscience Frontiers 13, no. 2 (March 2022): 101339. http://dx.doi.org/10.1016/j.gsf.2021.101339.

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Stephenson, R. A., T. Yegorova, M. F. Brunet, S. Stovba, M. Wilson, V. Starostenko, A. Saintot, and N. Kusznir. "Late Palaeozoic intra- and pericratonic basins on the East European Craton and its margins." Geological Society, London, Memoirs 32, no. 1 (2006): 463–79. http://dx.doi.org/10.1144/gsl.mem.2006.032.01.29.

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Cocks, L. Robin M., and Trond H. Torsvik. "The Palaeozoic geography of Laurentia and western Laurussia: A stable craton with mobile margins." Earth-Science Reviews 106, no. 1-2 (May 2011): 1–51. http://dx.doi.org/10.1016/j.earscirev.2011.01.007.

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Ootes, Luke, William J. Davis, Valerie A. Jackson, and Otto van Breemen. "Chronostratigraphy of the Hottah terrane and Great Bear magmatic zone of Wopmay Orogen, Canada, and exploration of a terrane translation model." Canadian Journal of Earth Sciences 52, no. 12 (December 2015): 1062–92. http://dx.doi.org/10.1139/cjes-2015-0026.

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The Paleoproterozoic Hottah terrane is the westernmost exposed bedrock of the Canadian Shield and a critical component for understanding the evolution of the Wopmay Orogen. Thirteen new high-precision U–Pb zircon crystallization ages are presented and support field observations of a volcano-plutonic continuum from Hottah terrane through to the end of the Great Bear magmatism, from >1950 to 1850 Ma. The new crystallization ages, new geochemical data, and newly published detrital zircon U–Pb data are used to challenge hitherto accepted models for the evolution of the Hottah terrane as an exotic arc and microcontinent that arrived over a west-dipping subduction zone and collided with the Slave craton at ca. 1.88 Ga. Although the Hottah terrane does have a tectonic history that is distinct from that of the neighbouring Slave craton, it shares a temporal history with a number of domains to the south and east — domains that were tied to the Slave craton by ca. 1.97 Ga. It is interpreted herein that Hottah terrane began to the south of its current position and evolved in an active margin over an always east-dipping subduction system that began prior to ca. 2.0 Ga and continued to ca. 1.85 Ga, and underwent tectonic switching and migration. The stratigraphy of the ca. 1913–1900 Ma Hottah plutonic complex and Bell Island Bay Group includes a subaerial rifting arc sequence, followed by basinal opening represented by marginal marine quartz arenite and overlying ca. 1893 Ma pillowed basalt flows and lesser rhyodacites. We interpret this stratigraphy to record Hottah terrane rifting off its parental arc crust — in essence the birth of the new Hottah terrane. This model is similar to rapidly rifting arcs in active margins — for example, modern Baja California. These rifts generally occur at the transition between subduction zones (e.g., Cocos–Rivera plates) and transtensional shear zones (e.g., San Andreas fault), and we suggest that extension-driven transtensional shearing, or, more simply, terrane translation, was responsible for the evolution of Bell Island Bay Group stratigraphy and that it transported this newly born Hottah terrane laterally (northward in modern coordinates), arriving adjacent to the Slave craton at ca. 1.88 Ga. Renewed east-dipping subduction led to the Great Bear arc flare-up at ca. 1876 Ma, continuing to ca. 1869 Ma. This was followed by voluminous Great Bear plutonism until ca. 1855 Ma. The model implies that it was the westerly Nahanni terrane and its subducting oceanic crust that collided with this active margin, shutting down the >120 million year old, east-dipping subduction system.

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Kolb, Jochen, Leon Bagas, and Marco L. Fiorentini. "Metallogeny of the North Atlantic Craton in Greenland." Mineralogical Magazine 79, no. 4 (August 2015): 815–55. http://dx.doi.org/10.1180/minmag.2015.079.4.01.

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AbstractThe North Atlantic Craton (NAC) extends along the coasts of southern Greenland. At its northern and southern margins, Archaean rocks are overprinted by Palaeoproterozoic orogeny or overlain by younger rocks. Typical granite-greenstone and granite-gneiss complexes represent the entire Archaean, with a hiatus from ∼3.55–3.20 Ga. In the granulite- and amphibolite-facies terranes, the metallogeny comprises hypozonal orogenic gold and Ni-PGE-Cr-Ti-V in mafic-ultramafic magmatic systems. Gold occurrences are widespread around and south of the capital, Nuuk. Nickel mineralization in the Maniitsoq Ni project is hosted in the Norite belt; Cr and PGE in Qeqertarssuatsiaq, and Ti-V in Sinarsuk in the Fiskenæsset complex. The lower-grade metamorphic Isua greenstone belt hosts the >1000 Mt Isua iron deposit in an Eoarchaean banded iron formation. Major Neoarchaean shear zones host mesozonal orogenic gold mineralization over considerable strike length in South-West Greenland. The current metallogenic model of the NAC is based on low-resolution data and variable geological understanding, and prospecting has been the main exploration method. In order to generate a robust understanding of the metal endowment, it is necessary to apply an integrated and collective approach. The NAC is similar to other well-endowed Archaean terranes but is underexplored, and is therefore likely to host numerous targets for greenfields exploration.

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Vervaet, François, and Fiona Darbyshire. "Crustal structure around the margins of the eastern Superior craton, Canada, from receiver function analysis." Precambrian Research 368 (January 2022): 106506. http://dx.doi.org/10.1016/j.precamres.2021.106506.

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Sneh, A., and A. Bein. "Platform carbonate cycles of Neocomian to Turonian age at the margins of the Arabian craton." Géologie Méditerranéenne 21, no. 3 (1994): 171–72. http://dx.doi.org/10.3406/geolm.1994.1556.

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Flöttmann, Thomas, and Robin Oliver. "Review of Precambrian-Palaeozoic relationships at the craton margins of southeastern Australia and adjacent Antarctica." Precambrian Research 69, no. 1-4 (October 1994): 293–306. http://dx.doi.org/10.1016/0301-9268(94)90093-0.

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Barley, M. E., T. S. Blake, and D. I. Groves. "The mount bruce megasequence set and eastern yilgarn craton: examples of late archaean to early proterozoic divergent and convergent craton margins and controls on mineralization." Precambrian Research 58, no. 1-4 (October 1992): 55–70. http://dx.doi.org/10.1016/0301-9268(92)90112-2.

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Ivanov, V. L. "Evolution of Antarctic prospective sedimentary basins." Antarctic Science 1, no. 1 (March 1989): 51–56. http://dx.doi.org/10.1017/s095410208900009x.

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No less than 15–20 sedimentary basins are now known on the Antarctic continental landmass and surrounding continental shelves. Reconstruction of their tectonic and stratigraphic evolution is a specialized task. Owing to the polar position of the continent, the Pacific and Atlantic global geostructures are closely spaced there and the interplay between them is strong enough to result in hybridization of the characteristic tectonic features of the various basins. The present morphostructure of the southern polar region of the Earth is characterized by a prominent circumpolar zoning. Therefore, the sedimentary basins form a gigantic ring along the continental margin, including both the shelf proper and the edge of the continent. Within the ring, the basins are associated with different types of margins successively replacing each other, from the Mesozoic magmatic are in the Pacific segment to the classic passive margin off East Antarctica. The formation of the sedimentary basins in the Antarctic segment of the Pacific mobile belt was a part of a single process of geosynclinal development, whereas on the craton flank the process was superposed on the continental structures by rifting during Gondwana fragmentation. During post-break-up tectonism, continental glaciation played an important part in the formation of the sedimentary basins.

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Kusky, Timothy M., Xiaoyong Li, Zhensheng Wang, Jianmin Fu, Luo Ze, and Peimin Zhu. "Are Wilson Cycles preserved in Archean cratons? A comparison of the North China and Slave cratons." Canadian Journal of Earth Sciences 51, no. 3 (March 2014): 297–311. http://dx.doi.org/10.1139/cjes-2013-0163.

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A review and comparison of the tectonic history of the North China and Slave cratons reveal that the two cratons have many similarities and some significant differences. The similarities rest in the conclusion that both cratons have a history of a Wilson Cycle, having experienced rifting of an old continent in the late Archean, development of a rift to passive margin sequence, collision of this passive margin with arcs within 100–200 Ma of the formation of the passive margin, reversal of subduction polarity, then eventual climactic collision with another arc terrane, microcontinental fragment, or continent. This cycle demonstrates the operation of Paleozoic-style plate tectonics in the late Archean. The main differences lie in the later tectonic evolution. The Slave’s post-cratonization history is dominated by subduction dipping away from the interior of the craton, and later incorporation into the interior of a larger continent, whereas the North China Craton has had a long history of subduction beneath the craton, including presently being located above the flat-lying Pacific slab resting in the mantle transition zone, placing it in a broad back-arc setting, with multiple mantle hydration events and collisions along its borders. The hydration enhances melting in the overlying mantle, and leads to melts migrating upwards to thermochemically erode the lithospheric root. This major difference may explain why the relatively small Slave craton preserves its thick Archean lithospheric root, whereas the eastern North China Craton has lost it.

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Li, Yilong, Jianping Zheng, Wenjiao Xiao, Guoqing Wang, and Fraukje M. Brouwer. "Circa 2.5 Ga granitoids in the eastern North China craton: Melting from ca. 2.7 Ga accretionary crust." GSA Bulletin 132, no. 3-4 (August 29, 2019): 817–34. http://dx.doi.org/10.1130/b35091.1.

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Abstract The Neoarchean crust-mantle interaction and crustal evolution of the North China craton are controversial and are instructive of the processes of continental crust growth and cratonic evolution. We present here a systematic study of the petrology, geochemistry, and geochronology of Neoarchean granitoids from the eastern North China craton to elucidate their petrogenesis and tectonic setting. The rocks were collected from the Jielingkou, Anziling, and Qinhuangdao plutons, and an amphibole-monzoporphyry dike in the Qinhuangdao pluton. Samples from the Jielingkou pluton, consisting dominantly of monzodiorite and diorite with minor monzonite and granodiorite, contain 52.2–64.4 wt% SiO2, 2.46–4.52 wt% MgO (Mg# = 0.41–0.54), 3.76–5.77 wt% Na2O, and K2O/Na2O ratios of 0.29–0.71. The Anziling pluton samples, comprising syenite and monzonite, display slightly higher SiO2 (60.9–66.7 wt%) and K2O/Na2O ratios (0.70–1.11), but lower MgO (1.54–2.33 wt%) and Mg# (0.40–0.47) values, compared to the Jielingkou rocks. The Qinhuangdao pluton samples, consisting mainly of granite and minor syenite and granodiorite, with some diorite and monzoporphyry dikes, are characterized by the highest SiO2 values (75.7–76.9 wt%) and K2O/Na2O ratios (0.73–1.41) and lowest MgO content (0.14–0.32 wt%) among the studied samples. The amphibole-monzoporphyry dike has intermediate SiO2 (56.3 wt%), high MgO (3.79 wt%), Na2O (5.55 wt%), and Mg# (0.45), and low K2O/Na2O ratio (0.66). Zircon U-Pb laser-ablation–inductively coupled plasma–mass spectrometry dating showed that all plutons have a ca. 2.5 Ga crystallization age. Zircon crystals have mildly positive εHf(t) values (+0.24 to +5.45) and a depleted mantle model age (TDM1) of ca. 2.7 Ga. We interpret the granitoid rocks as sanukitoid-related, Closepet-type granites, potassium-rich adakites, and potassium-rich granitoid rocks that crystallized in the late Neoarchean (2.5 Ga) and were derived from partial melting of mantle peridotite that was metasomatized with the addition of slab melt, thickened alkali-rich juvenile lower crust and juvenile metamorphosed tonalitic rocks. Mantle plume activity ca. 2.7 Ga is thought to have been responsible for the early Neoarchean tectono-thermal event in the eastern North China craton. This activity resulted in a major crustal accretion period in the craton, with subordinate crustal reworking at its margins. A steep subduction regime between ca. 2.55 Ga and ca. 2.48 Ga led to the remelting of older crustal material, with subordinate crustal accretion by magma upwelling from a depleted mantle source resulting in late Neoarchean underplating. This crustal reworking and underplating resulted in the widespread ca. 2.5 Ga plutons in the eastern North China craton. Continental crust growth in the North China craton thus occurred in multiple stages, in response to mantle plume activity, as well as protracted subduction-related granitoid magmatism during the Neoarchean.

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Şengör, A. M. Celâl, Boris A. Natal'in, Gürsel Sunal, and Rob van der Voo. "The Tectonics of the Altaids: Crustal Growth During the Construction of the Continental Lithosphere of Central Asia Between ∼750 and ∼130 Ma Ago." Annual Review of Earth and Planetary Sciences 46, no. 1 (May 30, 2018): 439–94. http://dx.doi.org/10.1146/annurev-earth-060313-054826.

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The largest mountain belt in Central Asia (∼9 million km2) is called the Altaids. It was assembled between ∼750 and ∼130 Ma ago around the western and southern margins of the Siberian Craton, partly on an older collisional system (the “Urbaykalides”). Geological, geophysical, and geochemical data—mostly high-resolution U-Pb ages—document the growth of only three arc systems in Central and Northwest Asia during this time period, an interval throughout which there were no major arc or continental collisions in the area. While the Altaids were being constructed as a Turkic-type orogen, continental crust grew in them by 1/3 of the global total. The Altaids thus added some 3 million km2to the continental crust over a period of 0.6 billion years, typical of Phanerozoic crustal growth rates.

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Stanley, George D. "Exotic terranes, late Paleozoic to early Mesozoic fossils and circum-Pacific events." Paleontological Society Special Publications 6 (1992): 277. http://dx.doi.org/10.1017/s2475262200008376.

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In addition to the breakup of Pangea, other major events occurring in the ancient Pacific during late Paleozoic and early Mesozoic time were the development and dispersal of exotic terranes which now characterize large portions of the eastern and western Pacific margins. While the terrane concept made sense out of the geologic crazy quiltwork pattern of these regions, considerable uncertainties still exist concerning terrane origins and their paleogeographic histories. Did terranes of the eastern and western pacific merely border Pangea or did they once exist within far-flung reaches of the ancient Pacific Ocean? Paleontology is now exploring and seeking answers to such issues based on benthic invertebrate fossils.Like examples in the western Pacific rim of Asia, the American Cordillera contains volcanic terranes with fossil content and history quite different from coeval rocks of the adjacent craton. Some terranes may have developed close to ancient North America, but others show evidence of having existed in settings far-removed from the craton. Over time, some terranes could have experienced considerable geographic displacement via tectonic processes (faulting, rift volcanism, seafloor spreading).Many terranes experienced protracted volcanic episodes of oceanic history during Permian and Triassic time. Terrane amalgamations occurred during Triassic and Jurassic time, and later in the Mesozoic were followed by accretion to the North American Craton. Some terranes such as Quesnellia, Cache Creek, Stikine, Wallowa, Eastern Klamath, and Wrangellia yield excellent benthic marine fossils—many of tropical Tethyan derivation, but other fossil assemblages are of mixed paleogeographic affiliations. Two island arc terranes, Stikinia and Wallowa, contribute to evolutionary and biogeographic issues with Triassic and Jurassic, tropical to temperate marine fossils. These include calcareous algae, sponges and corals occurring in reef sequences which can be related to better known examples from Asia and the former Tethys region. Continuing paleontological investigations into fossils from exotic terranes of the Cordilleran region, offer promise in the resolution of late Paleozoic and early Mesozoic circum-Pacific events and in the attainment of unified views of global paleogeography.

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39

Bogossian, Jessica, Anthony I. S. Kemp, and Steffen G. Hagemann. "Linking Gold Systems to the Crust-Mantle Evolution of Archean Crust in Central Brazil." Minerals 11, no. 9 (August 30, 2021): 944. http://dx.doi.org/10.3390/min11090944.

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The Goiás Archean Block (GAB) in central Brazil is an important gold district that hosts several world-class orogenic gold deposits. A better comprehension of the crustal, tectono-magmatic, and metallogenic settings of the GAB is essential to accurately define its geological evolution, evaluate Archean crustal growth models, and target gold deposits. We present an overview of gold systems, regional whole-rock Sm-Nd analyses that have been used to constrain the geological evolution of the GAB, and augment this with new in situ zircon U-Pb and Hf-O isotope data. The orogenic gold deposits show variable host rocks, structural settings, hydrothermal alteration, and ore mineralogy, but they represent epigenetic deposits formed during the same regional hydrothermal event. The overprinting of metamorphic assemblages by ore mineralogy suggests the hydrothermal event is post-peak metamorphism. The metamorphic grade of the host rocks is predominantly greenschist, locally reaching amphibolite facies. Isotope-time trends support a Mesoarchean origin of the GAB, with ocean opening at 3000–2900 Ma, and reworking at 2800–2700 Ma. Crustal growth was dominated by subduction processes via in situ magmatic additions along lithospheric discontinuities and craton margins. This promoted a crustal architecture composed of young, juvenile intra-cratonic terranes and old, long-lived reworked crustal margins. This framework provided pathways for magmatism and fluids that drove the gold endowment of the GAB.

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Sawant, Sariput S., K. Vijaya Kumar, V. Balaram, D. V. Subba Rao, K. S. Rao, and R. P. Tiwari. "Geochemistry and Genesis of Craton-derived Sediments from Active Continental Margins: Insights from the Mizoram Foreland Basin, NE India." Chemical Geology 470 (October 2017): 13–32. http://dx.doi.org/10.1016/j.chemgeo.2017.08.020.

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Kravchenko, Alexander, Boris Gerasimov, Evgeniy Loskutov, Alexander Okrugin, Larisa Galenchikova, and Vasily Beryozkin. "Statistical Models of the Distribution of Chemical Elements in Precambrian Rocks of the Siberian Craton." Separations 8, no. 3 (February 25, 2021): 23. http://dx.doi.org/10.3390/separations8030023.

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Natural chemical systems are an excellent object for studying the properties of various elements. The most diverse and informative geological complexes are crystalline rocks of the Precambrian. These rocks are exposed near the northern and southern margins of the Siberian craton. The chemical composition of rocks, the contents of impurity elements, and metals were studied by us using chemical and spectral analysis methods. Microprobe studies were performed. Using regression and multivariate statistical methods of analysis, the regularities of the distribution of chemical elements were found. It is shown that the distribution of precious metals and carbon dioxide in rocks is attributed to their chemical properties and comparable with close in-chemical properties’ rock-forming elements. It is found that the factor analysis reflects the uniform regularities of the distribution of elements in different regions and rocks. These regularities are similar on macro and micro levels. Comparison of the distribution patterns with the results of geochemical and petrological studies of other authors shows the leading role of the redox potential and acidity of the environment in the formation of rocks and minerals. The role of mathematical statistics for solving problems of chemical petrology and chemical systems analysis is underlined.

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Culshaw, Nicholas G., and D. Barrie Clarke. "Structural history and granite emplacement in the Rottenstone Domain during closure of the Trans-Hudson Orogen, Davin Lake, northern Saskatchewan." Canadian Journal of Earth Sciences 46, no. 4 (April 2009): 287–306. http://dx.doi.org/10.1139/e09-021.

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The Rottenstone Domain at Davin Lake northern Saskatchewan, exhibits structural and granite-emplacement evidence for crustal thickening, and possible Himalayan-style extrusion, overprinted by transpressional strain increasing toward the contact with the Wathaman Batholith. Three discrete Rottenstone subdomains parallel the regional strike of the Trans-Hudson Orogen: (i) the southeast Rottenstone subdomain (SERSD) with gently northwest-dipping migmatitic straight gneiss (S1) and white granitoid rocks with pinch-and-swell structures parallel to the straight gneissosity; (ii) the central Rottenstone subdomain (CRSD), which partly preserves the same NW-dipping fabric (S1) but is overprinted at its margins by tight upright F2 folds and includes a stockwork of pink monzogranitic aplites and pegmatites; and (iii) the northwest Rottenstone subdomain (NWRSD) in which the F2 folds are generally tighter and penetrative and its network of narrow white granitoid rocks is deformed and transposed by the F2 folds; but in the northwestern part, a wide, syn-D2 complex of schlieric white tonalitic and diatexite sheets strikes parallel the orogen. The SERSD D1 straight zone may be a remnant of Himalayan-type extrusion zone although it could be the lowest member of a stack of ductile thrust sheets. The CRSD stockwork may represent fluid-assisted magma injection into extensional fractures above the postulated extrusion zone. The increasing transpressional strain northwestward expressed primarily by the F2 folds in CRSD and NWRSD defines the Davin Lake shear zone, into which the NWRSD granitoid dyke complex represents syntectonic magma injection. Both the postulated extrusion and transpression are related to oblique convergence of the Archean Sask craton with the Archean Rae–Hearne craton.

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Klett, T. R., C. J. Wandrey, and J. K. Pitman. "Assessment of undiscovered petroleum resources of the north and east margins of the Siberian craton north of the Arctic Circle." Geological Society, London, Petroleum Geology Conference series 7, no. 1 (2010): 621–31. http://dx.doi.org/10.1144/0070621.

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Beranek, Luke P., Victoria Pease, Robert A. Scott, and Tonny B. Thomsen. "Detrital zircon geochronology of Ediacaran to Cambrian deep-water strata of the Franklinian basin, northern Ellesmere Island, Nunavut: implications for regional stratigraphic correlations." Canadian Journal of Earth Sciences 50, no. 10 (October 2013): 1007–18. http://dx.doi.org/10.1139/cjes-2013-0026.

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Enigmatic successions of deep-water strata referred to as the Nesmith beds and Grant Land Formation comprise the exposed base of the Franklinian passive margin sequence in northern Ellesmere Island, Nunavut. To test stratigraphic correlations with Ediacaran to Cambrian shallow-water strata of the Franklinian platform that are inferred by regional basin models, >500 detrital zircons from the Nesmith beds and Grant Land Formation were analyzed for sediment provenance analysis using laser ablation (LA–ICP–MS) and ion-microprobe (SIMS) methods. Samples of the Nesmith beds and Grant Land Formation are characterized by 1000–1300, 1600–2000, and 2500–2800 Ma detrital zircon age distributions and indicate provenance from rock assemblages of the Laurentian craton. In combination with regional stratigraphic constraints, these data support an Ediacaran to Cambrian paleodrainage model that features the Nesmith beds and Grant Land Formation as the offshore marine parts of a north- to northeast-directed depositional network. Proposed stratigraphic correlations between the Nesmith beds and Ediacaran platformal units of northern Greenland are consistent with the new detrital zircon results. Cambrian stratigraphic correlations within northern Ellesmere Island are permissive, but require further investigation because the Grant Land Formation provenance signatures agree with a third-order sedimentary system that has been homogenized by longshore current or gravity-flow processes, whereas coeval shallow-water strata yield a restricted range of detrital zircon ages and imply sources from local drainage areas or underlying rock units. The detrital zircon signatures of the Franklinian passive margin resemble those for the Cordilleran and Appalachian passive margins of Laurentia, which demonstrates the widespread recycling of North American rock assemblages after late Neoproterozoic continental rifting and breakup of supercontinent Rodinia.

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Hynes, Andrew, and Toby Rivers. "Protracted continental collision — evidence from the Grenville OrogenThis article is one of a series of papers published in this Special Issue on the theme Lithoprobe — parameters, processes, and the evolution of a continent." Canadian Journal of Earth Sciences 47, no. 5 (May 2010): 591–620. http://dx.doi.org/10.1139/e10-003.

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The Grenville Orogen in North America is interpreted to have resulted from collision between Laurentia and another continent, probably Amazonia, at ca. 1100 Ma. The exposed segment of the orogen was derived largely from reworked Archean to Paleoproterozoic Laurentian crust, products of a long-lived Mesoproterozoic continental-margin arc and associated back arc, and remnants of one or more accreted mid-Mesoproterozoic island-arc terranes. A potential suture, preserved in Grenvillian inliers of the southeastern USA, may separate rocks of Laurentian and Amazonian affinities. The Grenvillian Orogeny lasted more than 100 million years. Much of the interior Grenville Province, with peak metamorphism at ca. 1090–1020 Ma, consists of uppermost amphibolite- to granulite-facies rocks metamorphosed at depths of ca. 30 km, but areas of lower crustal, eclogite-facies nappes metamorphosed at 50–60 km depth also occur and an orogenic lid that largely escaped Grenvillian metamorphism is preserved locally. Overall, deformation and regional metamorphism migrated sequentially to the northwest into the Laurentian craton, with the youngest contractional structures in the northwestern part of the orogen at ca. 1000–980 Ma. The North American lithospheric root extends across part of the Grenville Orogen, where it may have been produced by depletion of sub-continental lithospheric mantle beneath the long-lived Laurentian-margin Mesoproterozoic subduction zone. Both the Grenville Orogen and the Himalaya–Tibet Orogen have northern margins characterized by long-lived subduction before continental collision and protracted convergence following collision. Both exhibit cratonward-propagating thrusting. In the Himalaya–Tibet Orogen, however, the pre-collisional Eurasian-margin arc is high in the structural stack, whereas in the Grenville Orogen, the pre-collisional continental-margin arc is low in the structural stack. We interpret this difference as due to subduction reversal in the Grenville case shortly before collision, so that the continental-margin arc became the lower plate during the ensuing orogeny. The structurally low position of the warm, extended Laurentian crust probably contributed significantly to the ductility of lower and mid-crustal Grenvillian rocks.

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Gan, Haonan, Junlai Liu, Guiling Wang, and Wei Zhang. "Evolution Characteristics through Thermo-Rheological Lithosphere of the Liaonan Metamorphic Core Complex, Eastern North China Craton." Minerals 12, no. 12 (December 6, 2022): 1570. http://dx.doi.org/10.3390/min12121570.

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Metamorphic core complexes are developed in crustal activity belts at the continental margins or within continents, and their main tectonic feature is that the ductile middle crust is exhumed at the surface. The deformation properties are closely related to the geodynamic process affecting the continental crust. However, the evolution of the metamorphic core complexes after their formation is still unclear. The Cretaceous Liaonan metamorphic core complex developed in the eastern North China craton provides an ideal environment to study its evolution. In this study, we estimate the paleo-temperature and paleo-stress at the time of formation of the metamorphic core complex dynamical recrystallization of quartz and calculate the thermo-rheological structure of the present Liaonan metamorphic core complex by one-dimensional steady-state heat conduction equation and power-creep law. The results show that compared with the Cretaceous period, the geothermal heat flow value of the present Liaonan metamorphic core complex decreases from 70–80 mW/m2 to 49.4 mW/m2, the thermal lithosphere thickness increases from 59–75 km to 173 km, and the brittle transition depth increases from 10–13 km to about 70 km, showing coupling of the crust–mantle rheological structure. We speculate that the evolution of the thermo-rheological structure of the Liaonan metamorphic core complex is possibly caused by rapid heat loss or lithospheric mantle flow in the Bohai Bay Basin.

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Toteu, Sadrack Félix, Joseph Penaye, and Yvette Poudjom Djomani. "Geodynamic evolution of the Pan-African belt in central Africa with special reference to Cameroon." Canadian Journal of Earth Sciences 41, no. 1 (January 1, 2004): 73–85. http://dx.doi.org/10.1139/e03-079.

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The Pan-African belt in central Africa has benefited from the many petrographic, structural, and geochronological studies in the recent years that have improved our understanding of the belt. However, those studies have also produced various and often divergent evolutionary models for the belt, some of which do not even involve well-defined cratons. Following a review of the available data in Cameroon, we propose a model of continentcontinent collision that involved the Congo craton and the north-central Cameroon active margin showing Archean to Paleoproterozoic inheritances. This model is based, among others, on (i) the prominent role of the Congo craton as demonstrated by the regional extension of external nappes on its northern edge and the concomitant exhumation of the 620 Ma granulitic rocks believed to have formed at the root of the collision zone, and (ii) the late development of a strike slip fault system in central Cameroon as the result of horizontal movement following the multistage collision. In the general framework of the Pan-Africano Brasiliano belt, a comparison of the kinematic and age of deformation north of the Congo craton to that east of the West African craton, suggests that the overall tectonic evolution of the mobile domain between both cratons is controlled by their relative motion.

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Klett, T. R., C. J. Wandrey, and J. K. Pitman. "Chapter 27 Geology and petroleum potential of the north and east margins of the Siberian Craton, north of the Arctic Circle." Geological Society, London, Memoirs 35, no. 1 (2011): 413–31. http://dx.doi.org/10.1144/m35.27.

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Lubnina, N. V., and A. I. Slabunov. "Karelian сrаtоn in the struсturе of the Nео-Аrсhаеаn supercontinent Kеnоrlаnd: nеw paleomagnetic and isotopic-geochronological data on granulites of the Onega complex." Moscow University Bulletin. Series 4. Geology, no. 5 (October 28, 2017): 3–15. http://dx.doi.org/10.33623/0579-9406-2017-5-3-15.

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New paleomagnetic and isotopic-geochronological data obtained for Neoarchean Onega granulite complex, were used to reconstruct the position of the Karelian craton in the Neoarchean supercontinent Kenorland. Geological correlations were made for the Karelian, Kaapvaal, Pilbara, Superior, and Slave cratons. Comparison of independent geological and paleomagnetic data allowed us to propose a new configuration of the Neoarchean supercontinent Kenorland. The position of the ancient core of the Karelian craton (the Vodlozero terrane), located in the North-Western margin of the supercontinent structure, reconstructed based on the previously paleomagnetic data for the Neoarchean Panozero sanukitoid massif and new one for granulite of Onega complex.

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Tappe, Sebastian, Stephen F. Foley, Andreas Stracke, Rolf L. Romer, Bruce A. Kjarsgaard, Larry M. Heaman, and Nancy Joyce. "Craton reactivation on the Labrador Sea margins: 40Ar/39Ar age and Sr–Nd–Hf–Pb isotope constraints from alkaline and carbonatite intrusives." Earth and Planetary Science Letters 256, no. 3-4 (April 2007): 433–54. http://dx.doi.org/10.1016/j.epsl.2007.01.036.

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Journal articles on the topic 'Craton margins'

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