THE PLATE TECTONIC APPROXIMATION: Plate Nonrigidity, Diffuse Plate Boundaries, and Global Plate Reconstructions

Full-plate reconstructions describe the history of both past continental motions and how plate boundaries have evolved to accommodate these motions. The fluxes of material into and out of the mantle at plate boundaries is thought to deeply influence the evolution of deep Earth structure, surface environments and biological systems through deep time. Traditionally, plate tectonic reconstructions have relied on geophysical data from the oceans, which provides details of how Pangea broke apart (since ca. 200 Myr) while paleomagnetism is the primary quantitative constraint prior to Pangea formation. However, these data do not directly constrain the extent of subduction zones or other plate boundaries, so reconstructing the past plate configurations of past supercontinents must rely on alternative methods. One source of data that can resolve this problem is to use observations from detrital zircons. Previous studies have proposed classification schemes to determine tectonic settings where samples were deposited, based on the different characteristic shapes of detrital zircon age spectra found in convergent, collisional and extensional settings.Here, we investigate the applicability of this method to test and refine global full-plate tectonic reconstructions in deep time, using a published database of zircon ages. We first use reconstructions for relatively recent times (<100 Ma), where reconstructions are reasonable well constrained, to evaluate the effectiveness of the classification method. For older times, where uncertainties in the reconstructions are far larger, we can use the results to discriminate between competing models. We analysed the proximity between reconstructed plate boundaries and zircon sample sites assigned to different tectonic classifications, and found that the classification method does well (~64&#65293;79% success depending on distance threshold used) in distinguishing convergent settings. The ability of the classification to define extensional settings such as rift basins is less clear, though samples in this class do lie preferentially further from convergent settings. Based on these insights, we apply the method to evaluate full-plate reconstructions for the Neoproterozoic as well as other competing models for the configuration of Rodinia.

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Uncertainties in break-up markers along the Iberia–Newfoundland margins illustrated by new seismic data

Solid Earth ◽

10.5194/se-11-397-2020 ◽

2020 ◽

Vol 11 (2) ◽

pp. 397-417 ◽

Cited By ~ 1

Author(s):

Annabel Causer ◽

Lucía Pérez-Díaz ◽

Jürgen Adam ◽

Graeme Eagles

Keyword(s):

Seismic Data ◽

Direct Consequence ◽

Magnetic Anomalies ◽

Oceanic Lithosphere ◽

High Amplitude ◽

Plate Tectonic ◽

Plate Models ◽

Plate Reconstructions ◽

Tectonic Reconstructions ◽

Break Up

Abstract. Plate tectonic modellers often rely on the identification of “break-up” markers to reconstruct the early stages of continental separation. Along the Iberian-Newfoundland margin, so-called break-up markers include interpretations of old magnetic anomalies from the M series, as well as the “J anomaly”. These have been used as the basis for plate tectonic reconstructions are based on the concept that these anomalies pinpoint the location of first oceanic lithosphere. However, uncertainties in the location and interpretation of break-up markers, as well as the difficulty in dating them precisely, has led to plate models that differ in both the timing and relative palaeo-positions of Iberia and Newfoundland during separation. We use newly available seismic data from the Southern Newfoundland Basin (SNB) to assess the suitability of commonly used break-up markers along the Newfoundland margin for plate kinematic reconstructions. Our data show that basement associated with the younger M-series magnetic anomalies is comprised of exhumed mantle and magmatic additions and most likely represents transitional domains and not true oceanic lithosphere. Because rifting propagated northward, we argue that M-series anomaly identifications further north, although in a region not imaged by our seismic, are also unlikely to be diagnostic of true oceanic crust beneath the SNB. Similarly, our data also allow us to show that the high amplitude of the J Anomaly is associated with a zone of exhumed mantle punctuated by significant volcanic additions and at times characterized by interbedded volcanics and sediments. Magmatic activity in the SNB at a time coinciding with M4 (128 Ma) and the presence of SDR packages onlapping onto a basement fault suggest that, at this time, plate divergence was still being accommodated by tectonic faulting. We illustrate the differences in the relative positions of Iberia and Newfoundland across published plate reconstructions and discuss how these are a direct consequence of the uncertainties introduced into the modelling procedure by the use of extended continental margin data (dubious magnetic anomaly identifications, break-up unconformity interpretations). We conclude that a different approach is needed for constraining plate kinematics of the Iberian plate pre-M0 times.

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Plate tectonic raster reconstruction in GPlates

Solid Earth Discussions ◽

10.5194/sed-6-793-2014 ◽

2014 ◽

Vol 6 (1) ◽

pp. 793-830

Author(s):

J. Cannon ◽

E. Lau ◽

R. D. Müller

Keyword(s):

Graphics Hardware ◽

Plate Tectonic ◽

Geological Time ◽

Raster Data ◽

Tectonic Plates ◽

Tectonic Reconstruction ◽

Reconstruction Software ◽

Plate Reconstructions ◽

Simple Implementation ◽

Novel Method

Abstract. We describe a novel method implemented in the GPlates plate tectonic reconstruction software to interactively reconstruct arbitrarily high-resolution raster data to past geological times using a rotation model. The approach is based on the projection of geo-referenced raster data into a cube map followed by a reverse projection onto rotated tectonic plates on the surface of the globe. This decouples the rendering of a geo-referenced raster from its reconstruction, providing a number of benefits including a simple implementation and the ability to combine rasters with different geo-referencing or inbuilt raster projections. The cube map projection is accelerated by graphics hardware in a wide variety of computer systems manufactured over the last decade. Furthermore, by integrating a multi-resolution tile partitioning into the cube map we can provide on-demand tile streaming, level-of-detail rendering and hierarchical visibility culling enabling researchers to visually explore essentially unlimited resolution geophysical raster data attached to tectonic plates and reconstructed through geological time. This capability forms the basis for interactively building and improving plate reconstructions in an iterative fashion, particularly for tectonically complex regions.

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Investigating the plate kinematics of continental blocks and their role on the deformation experienced along the Iberia-Eurasia plate boundary using deformable plate tectonic models

10.5194/egusphere-egu21-1402 ◽

2021 ◽

Author(s):

Michael King ◽

Kim Welford ◽

Patricia Cadenas ◽

Julie Tugend

Keyword(s):

Plate Boundary ◽

Magnetic Anomalies ◽

Collective Impact ◽

Plate Tectonic ◽

Alpine Orogeny ◽

Tectonic Plates ◽

Plate Models ◽

Plate Reconstructions ◽

Kinematic Models ◽

Plate Kinematics

The kinematics of the Iberian plate during Mesozoic extension and subsequent Alpine compression and their implications on the partitioning of strain experienced across the Iberia-Europe plate boundary continue to be a subject of scientific interest, and debate. To date, the majority of plate tectonic models only consider the motion of rigid tectonic plates. In addition, the lack of consideration for the kinematics of intra-continental domains and intervening continental blocks in-between has led to numerous discrepancies between rigid plate kinematic models of Iberia, based mainly on tight-fit reconstruction of M-series magnetic anomalies, and their ability to reconcile geological and geophysical observations. To address these discrepancies, deformable plate tectonic models constrained by previous plate reconstructions, geological, and geophysical studies are built using the GPlates software to study the evolution of deformation experienced along the Iberia-Eurasia plate boundary from the Triassic to present day. These deformable plate models consider the kinematics of small intra-continental blocks such as the Landes High and Ebro Block situated between large tectonic plates, their interplay with pre-existing structural trends, and the collective impact of these phenomena on the deformation experienced during Mesozoic rifting and Alpine compressional re-activation along the Iberia-European plate boundary. Preliminary results suggest that the independent kinematics of the Landes High played a key role on the distribution of oblique extension between different rift arms and resultant deformation within the Bay of Biscay. Within the Pyrenean realm, deformation experienced prior to and during the Alpine Orogeny was more largely controlled by the interplay between the Ebro Block kinematics and rift segmentation induced by the orientation of inherited trends.

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Emergence of plate tectonic during the Archean: insights from 3D numerical modelling.

10.5194/egusphere-egu21-8809 ◽

2021 ◽

Author(s):

Andrea Piccolo ◽

Boris Kaus ◽

Richard White ◽

Nicolas Arndt ◽

Nicolas Riel

Keyword(s):

Phase Transitions ◽

Subduction Zones ◽

Plate Tectonics ◽

Large Scale ◽

Potential Temperature ◽

Secular Change ◽

Plate Boundaries ◽

Plate Tectonic ◽

Subduction Initiation ◽

The Earth

In the plate tectonic convection regime, the external lid is subdivided into discrete plates that move independently. Although it is known that the system of plates is mainly dominated by slab-pull forces, it is not yet clear how, when and why plate tectonics became the dominant geodynamic process in our planet. It could have started during the Meso-Archean (3.0-2.9 Ga). However, it is difficult to conceive a subduction driven system at the high mantle potential temperatures (Tp) that are thought to have existed around that time, because Tp controls the thickness and the strength of the compositional lithosphere making subduction unlikely. In recent years, however, a credible solution to the problem of subduction initiation during the Archean has been advanced, invoking a plume-induced subduction mechanism[1] that seems able to generate plate-tectonic like behaviour to first order. However, it has not yet been demonstrated how these tectonic processes interact with each other, and whether they are able to eventually propagate to larger scale subduction zones.The Archean Eon was characterized by a high Tp[2], which generates weaker plates, and a thick and chemically buoyant lithosphere. In these conditions, slab pull forces are inefficient, and most likely unable to be transmitted within the plate. Therefore, plume-related proto-plate tectonic cells may not have been able to interact with each other or showed a different interaction as a function of mantle potential temperature and composition of the lithosphere. Moreover, due to secular change of Tp, the dynamics may change with time. In order to understand the complex interaction between these tectonic seeds it is necessary to undertake large scale 3D numerical simulations, incorporating the most relevant phase transitions and able to handle complex constitutive rheological model.Here, we investigate the effects of the composition and Tp independently to understand the potential implications of the interaction of plume-induced subduction initiation. We employ a finite difference visco-elasto-plastic thermal petrological code using a large-scale domain (10000 x 10000 x 1000 km along x, y and z directions) and incorporating the most relevant petrological phase transitions. We prescribed two oceanic plateaus bounded by subduction zones and we let the negative buoyancy and plume-push forces evolve spontaneously. The paramount question that we aim to answer is whether these configurations allow the generation of stable plate boundaries. The models will also investigate whether the presence of continental terrain helps to generate plate-like features and whether the processes are strong enough to generate new continental terrains&#160;or assemble them .&#160;[1]&#160;&#160;&#160;&#160;&#160;&#160; T. V. Gerya, R. J. Stern, M. Baes, S. V. Sobolev, and S. A. Whattam, &#8220;Plate tectonics on the Earth triggered by plume-induced subduction initiation,&#8221; Nature, vol. 527, no. 7577, pp. 221&#8211;225, 2015.[2]&#160;&#160;&#160;&#160;&#160;&#160; C. T. Herzberg, K. C. Condie, and J. Korenaga, &#8220;Thermal history of the Earth and its petrological expression,&#8221; Earth Planet. Sci. Lett., vol. 292, no. 1&#8211;2, pp. 79&#8211;88, 2010.[3]&#160;&#160;&#160;&#160;&#160;&#160; R. M. Palin, M. Santosh, W. Cao, S.-S. Li, D. Hern&#225;ndez-Uribe, and A. Parsons, &#8220;Secular metamorphic change and the onset of plate tectonics,&#8221; Earth-Science Rev., p. 103172, 2020.

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Plate tectonic modelling: review and perspectives

Geological Magazine ◽

10.1017/s0016756817001030 ◽

2018 ◽

Vol 156 (2) ◽

pp. 208-241 ◽

Cited By ~ 2

Author(s):

CHRISTIAN VÉRARD

Keyword(s):

Plate Boundaries ◽

Dual Control ◽

Plate Tectonic ◽

Joint Effort ◽

Tectonic Plate ◽

Deep Time ◽

Tectonic Plates ◽

Control Approach ◽

New Frontier ◽

Tectonic Boundaries

AbstractSince the 1970s, numerous global plate tectonic models have been proposed to reconstruct the Earth's evolution through deep time. The reconstructions have proven immensely useful for the scientific community. However, we are now at a time when plate tectonic models must take a new step forward. There are two types of reconstructions: those using a ‘single control’ approach and those with a ‘dual control’ approach. Models using the ‘single control’ approach compile quantitative and/or semi-quantitative data from the present-day world and transfer them to the chosen time slices back in time. The reconstructions focus therefore on the position of tectonic elements but may ignore (partially or entirely) tectonic plates and in particular closed tectonic plate boundaries. For the readers, continents seem to float on the Earth's surface. Hence, the resulting maps look closer to what Alfred Wegener did in the early twentieth century and confuse many people, particularly the general public. With the ‘dual control’ approach, not only are data from the present-day world transferred back to the chosen time slices, but closed plate tectonic boundaries are defined iteratively from one reconstruction to the next. Thus, reconstructions benefit from the wealth of the plate tectonic theory. They are physically coherent and are suited to the new frontier of global reconstruction: the coupling of plate tectonic models with other global models. A joint effort of the whole community of geosciences will surely be necessary to develop the next generation of plate tectonic models.

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Plate tectonic chain reaction constrained from noise in the Cretaceous Quiet Zone

10.5194/egusphere-egu2020-2777 ◽

2020 ◽

Author(s):

Derya Gürer ◽

Roi Granot ◽

Douwe J.J. van Hinsbergen

Keyword(s):

Subduction Zones ◽

Kinematic Model ◽

Plate Boundary ◽

Western Mediterranean ◽

Plate Motion ◽

Plate Boundaries ◽

Plate Tectonic ◽

Test Bed ◽

Chain Reaction ◽

Tectonic Plates

The relative motions of the tectonic plates show remarkable variation throughout Earth&#8217;s history. Major changes in relative motion between the tectonic plates are traditionally viewed as spatially and temporally isolated events linked to forces acting on plate boundaries (i.e., formation of same-dip double subduction zones, changes in the strength of the boundary), or thought to be associated with mantle dynamics. A Cretaceous global plate reorganization event has been postulated to have affected all major plates. The Cretaceous &#8216;swing&#8217; in Africa-Eurasia relative plate motion provides an ideal test-bed for assessing the temporal and spatial evolution of both relative plate motions and surrounding geological markers. Here we show a novel plate kinematic model for the closure of the Tethys Ocean by implementing intra-Cretaceous Quiet Zone time markers and combine the results with the geological constraints found along the convergent plate boundary. Our results allow to assess the order, causes and consequences of geological events and unravel a chain of tectonic events that set off with the onset of horizontally-forced double subduction ~105 Myr ago, followed by a 40 Myr long period of acceleration of the Africa relative to Eurasia that peaked at 80 Myr ago (at rates four times as high as previously predicted). This acceleration, which was likely caused by the pull of two same-dip subduction zones was followed by a sharp decrease in plate velocity, when double subduction terminated with ophiolite obduction onto the African margin. These tectonic forces acted on the eastern half of the Africa-Eurasia plate boundary, which led to counterclockwise rotation of Africa and sparked new subduction zones in the western Mediterranean region. Our analysis identifies the Cretaceous double subduction episode between Africa and Eurasia as a link in the global plate tectonic chain reaction and provides a dynamic view on plate reorganizations.

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Full-plate modelling in pre-Jurassic time

Geological Magazine ◽

10.1017/s0016756817001005 ◽

2017 ◽

Vol 156 (2) ◽

pp. 261-280 ◽

Cited By ~ 6

Author(s):

MATHEW DOMEIER ◽

TROND H. TORSVIK

Keyword(s):

Continental Drift ◽

Oceanic Lithosphere ◽

Plate Boundaries ◽

Plate Tectonic ◽

Plate Models ◽

Fertile Ground ◽

Alternative Means ◽

History Of

AbstractA half-century has passed since the dawning of the plate tectonic revolution, and yet, with rare exception, palaeogeographic models of pre-Jurassic time are still constructed in a way more akin to Wegener's paradigm of continental drift. Historically, this was due to a series of problems – the near-complete absence ofin situoceanic lithosphere older than 200 Ma, a fragmentary history of the latitudinal drift of continents, unconstrained longitudes, unsettled geodynamic concepts and a lack of efficient plate modelling tools – which together precluded the construction of plate tectonic models. But over the course of the last five decades strategies have been developed to overcome these problems, and the first plate model for pre-Jurassic time was presented in 2002. Following on that pioneering work, but with a number of significant improvements (most notably longitude control), we here provide a recipe for the construction of full-plate models (including oceanic lithosphere) for pre-Jurassic time. In brief, our workflow begins with the erection of a traditional (or ‘Wegenerian’) continental rotation model, but then employs basic plate tectonic principles and continental geology to enable reconstruction of former plate boundaries, and thus the resurrection of lost oceanic lithosphere. Full-plate models can yield a range of testable predictions that can be used to critically evaluate them, but also novel information regarding long-term processes that we have few (or no) alternative means of investigating, thus providing exceptionally fertile ground for new exploration and discovery.

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Phanerozoic paleogeographic, plate tectonic and paleoclimatic reconstructions

The Paleontological Society Special Publications ◽

10.1017/s2475262200008236 ◽

1992 ◽

Vol 6 ◽

pp. 263-263 ◽

Cited By ~ 1

Author(s):

Christopher R. Scotese

Keyword(s):

General Circulation ◽

Subduction Zones ◽

Coastal Upwelling ◽

Hot Spot ◽

Circulation Model ◽

Time Interval ◽

Plate Boundaries ◽

Plate Tectonic ◽

Prevailing Wind Direction ◽

Event Stratigraphy

In 1913, in the concluding remarks to his two volume compendium, Principles of Stratigraphy, Amadeus Grabau wrote, “When the science of Stratigraphy has developed so that its basis is no longer purely or chiefly paleontological, and when the sciences of Lithogenisis and Orogenesis … are given their due share in the comprehensive investigation of the history of the earth, then we may hope that Paleogeography, the youthful daughter science of Stratigraphy will have attained unto that stature that will make it the crowning attraction to the student of earth history.” It has taken nearly 80 years for Grabau's vision to be realized. The fruits of the plate tectonic revolution combined with our new understanding of global eustasy and event stratigraphy, make it now possible to map the changing geography of the earth's surface with unparalleled detail and accuracy.In this poster session, we present 28 paleogeographic maps illustrating the changing configuration of mountains, land, shallow seas, and deep ocean basins during the Phanerozoic. The plate boundaries (spreading ridges, subduction zones, and transform faults) that were active during each time interval are also shown. For the Mesozoic and Cenozoic these plate boundaries are based on a synthesis of linear magnetic anomaly data and fracture zone locations compiled by PALEOMAP Project (International Lithosphere Program). The Mesozoic and Cenozoic orientation of the continents relative to the Earth's axis of rotation has been determined using a combination of paleomagnetic data and hot spot tracks. The location of Paleozoic plate boundaries, though speculative, is based evidence of past subduction and inferred sea floor spreading. The relative longitudinal positions of the continents and the width of the intervening Paleozoic oceans have been adjusted to best explain changing biogeographic and paleoclimatic patterns.The land, sea and mountain distributions portrayed on these 28 paleogeographic reconstructions have been used as input for a series of computer simulations of paleoclimate. The paleoclimatic model, which was developed by C.R. Scotese and M. I. Ross, uses the latitudinal distribution of land and sea, as well as the orientation of ancient mountain belts to predict the distr ibution of high and low pressure cells, prevailing wind direction, relative wetness/dryness, as well as zones of coastal upwelling. This model, which takes a simple parametric approach, makes predictions which are similar to the more robust General Circulation Model (GCM), but requires far less computer resources.

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Recognising spatially and geochemically anomalous arc magmatism (SGAM) and implications for plate tectonic reconstructions

10.5194/egusphere-egu21-6932 ◽

2021 ◽

Author(s):

Gideon Rosenbaum ◽

John Caulfield ◽

Teresa Ubide ◽

Jack Ward ◽

Mike Sandiford ◽

...

Keyword(s):

South America ◽

Volcanic Rocks ◽

Plate Boundaries ◽

Arc Magmatism ◽

Potential Contribution ◽

Plate Tectonic ◽

Geochemical Anomaly ◽

Tectonic Reconstructions ◽

Slab Tearing ◽

Subducting Slab

Subduction zones generate volcanic arcs, but there are many examples where magmatism in convergent plate boundaries occurs in unexpected locations relative to the subducting slab. These magmas are commonly also geochemically anomalous relative to the composition of neighbouring typical subduction-related rocks. The origin of such Spatially and Geochemically Anomalous arc Magmatism (SGAM) may correspond to local variations in subduction parameters, the presence of crustal and lithospheric heterogeneities, or the potential contribution of melts generated by slab tearing and slab edge effects. Using the Holocene volcanoes in South America as a case study, we investigated spatial and geochemical patterns of volcanism along the Andean volcanic belt. Based on a series of geochemical indices, we developed a scoring system for the composition of volcanic rocks, with the lowest and highest scores indicating &#8216;typical&#8217; and &#8216;anomalous&#8217; arc melting processes, respectively. The results show that a number of Holocene volcanoes in South America can be unambiguously defined as SGAM. Volcanism in these localities may correspond to disruptions in the geometry of the subducting slab, or to areas affected by mantle flow in the proximity of the slab edge. To test the potential applicability of this method for plate tectonic reconstructions, we calculated geochemical anomaly scores for whole-rock analyses of volcanic rocks from other convergent boundary settings. The results show that high geochemical anomaly scores are obtained in areas where slab tearing has been documented or postulated, such as in Mount Etna (Sicily). The occurrence of anomalous magmatic rocks in older convergent plate boundary settings (e.g., Neogene rocks from the Gibraltar area) corroborates plate tectonic reconstructions that incorporated processes such as subduction segmentation, slab tearing, and the development of asthenospheric windows. Accordingly, we suggest that the recognition of SGAM from other modern and ancient arc settings may inform on similar types of processes, even in cases where the three-dimensional slab structure is no longer detectable.

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