Artículos de revistas: "Lithospheric Deformation"

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Dérerová, Jana, Miroslav Bielik, Mariana Pašiaková, Igor Kohút y Petra Hlavńová. "Calculation of temperature distribution and rheological properties of the lithosphere along transect II in the Western Carpathian-Pannonian Basin region". Contributions to Geophysics and Geodesy 44, n.º 2 (1 de junio de 2014): 149–60. http://dx.doi.org/10.2478/congeo-2014-0009.

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Abstract The temperature model of the lithosphere along transect II passing through the Western Carpathians and the Pannonian Basin has been calculated using 2D integrated geophysical modelling methodology. Based on the extrapolation of failure criteria, lithology and calculated temperature distribution, we derived the rheology model of the lithosphere in the area. Our results indicate a decrease of the lithospheric strength from the European platform and the Western Carpathians towards the Pannonian Basin. The largest strength can be observed within the upper crust which suggests rigid deformation in this part of the lithosphere. In the lithospheric mantle, strength almost disappears which allows us to assume that the ductile deformation dominates in this part of the lithosphere

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2

Kelly, Sean, Christopher Beaumont y Jared P. Butler. "Inherited terrane properties explain enigmatic post-collisional Himalayan-Tibetan evolution". Geology 48, n.º 1 (28 de octubre de 2019): 8–14. http://dx.doi.org/10.1130/g46701.1.

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Abstract Observations highlight the complex tectonic, magmatic, and geodynamic phases of the Cenozoic post-collisional evolution of the Himalayan-Tibetan orogen and show that these phases migrate erratically among terranes accreted to Asia prior to the Indian collision. This behavior contrasts sharply with the expected evolution of large, hot orogens formed by collision of lithospheres with laterally uniform properties. Motivated by this problem, we use two-dimensional numerical geodynamical model experiments to show that the enigmatic behavior of the Himalayan-Tibetan orogeny can result from crust-mantle decoupling, transport of crust relative to the mantle lithosphere, and diverse styles of lithospheric mantle delamination, which emerge self-consistently as phases in the evolution of the system. These model styles are explained by contrasting inherited mantle lithosphere properties of the Asian upper-plate accreted terranes. Deformation and lithospheric delamination preferentially localize in terranes with the most dense and weak mantle lithosphere, first in the Qiangtang and then in the Lhasa mantle lithospheres. The model results are shown to be consistent with 11 observed complexities in the evolution of the Himalayan-Tibetan orogen. The broad implication is that all large orogens containing previously accreted terranes are expected to have an idiosyncratic evolution determined by the properties of these terranes, and will be shown to deviate from predictions of uniform lithosphere models.

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3

McNutt, Marcia. "Lithospheric stress and deformation". Reviews of Geophysics 25, n.º 6 (1987): 1245. http://dx.doi.org/10.1029/rg025i006p01245.

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4

Lamarque, Gaelle y Jordi Julià. "Lithospheric and sublithospheric deformation under the Borborema Province of northeastern Brazil from receiver function harmonic stripping". Solid Earth 10, n.º 3 (21 de junio de 2019): 893–905. http://dx.doi.org/10.5194/se-10-893-2019.

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Abstract. The depth-dependent anisotropic structure of the lithosphere under the Borborema Province in northeast Brazil has been investigated via harmonic stripping of receiver functions developed at 39 stations in the region. This method retrieves the first (k=1) and second (k=2) degree harmonics of a receiver function dataset, which characterize seismic anisotropy beneath a seismic station. Anisotropic fabrics are in turn directly related to the deformation of the lithosphere from past and current tectonic processes. Our results reveal the presence of anisotropy within the crust and the lithospheric mantle throughout the entire province. Most stations in the continental interior report consistent anisotropic orientations in the crust and lithospheric mantle, suggesting a dominant northeast–southwest pervasive deformation along lithospheric-scale shear zones developed during the Brasiliano–Pan-African orogeny. Several stations aligned along a northeast–southwest trend located above the (now aborted) Mesozoic Cariri–Potiguar rift display large uncertainties for the fast-axis direction. This non-azimuthal anisotropy may be related to a complex anisotropic fabric resulting from a combination of deformation along the ancient collision between Precambrian blocks, Mesozoic extension and thermomechanical erosion dragging by sublithospheric flow. Finally, several stations along the Atlantic coast reveal depth-dependent anisotropic orientations roughly (sub)perpendicular to the margin. These results suggest a more recent overprint, probably related to the presence of frozen anisotropy in the lithosphere due to stretching and rifting during the opening of the South Atlantic.

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5

Wilson, Terry J. "Processes of continental Lithospheric Deformation". Geochimica et Cosmochimica Acta 54, n.º 10 (octubre de 1990): 2899–900. http://dx.doi.org/10.1016/0016-7037(90)90030-o.

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6

Dehler, S. A. y C. E. Keen. "Effects of rifting and subsidence on thermal evolution of sediments in Canada's east coast basins". Canadian Journal of Earth Sciences 30, n.º 9 (1 de septiembre de 1993): 1782–98. http://dx.doi.org/10.1139/e93-158.

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Regional maps of lithospheric deformation and thermal history have been derived for the eastern continental margin of Canada. Subsidence associated with the rifting and cooling stages of rifted margin formation was calculated from gridded maps of sediment thickness and bathymetry along the Labrador, Grand Banks, and Nova Scotian margins. A two-layer lithospheric extension model was used to compute the deformation and thermal evolution of each region. Deformation results show that the crust and lower lithosphere have generally stretched by different amounts, and that either crustal or subcrustal lithospheric stretching dominates beneath the various basins. Thermal modelling results for the older Nova Scotian and Grand Banks margins show a strong correlation between thermal gradient, crustal stretching, and sediment thickness, and the predicted thermal gradient pattern for the younger Labrador margin correlates extremely well with predicted stretching of the still-cooling subcrustal lithosphere. Predictions of sediment maturity (vitrinite reflectance) of basin deposits were obtained from the derived time – temperature histories. Model results have been constrained with observations from individual boreholes and extrapolated away from these well-constrained areas into regions beyond the frontiers of present exploration. Results are presented as maps showing depths to present-day peak thermal maturity zones and the ages at which earliest post-rift sediments reached peak maturity levels. This reconnaissance approach has led to predictions of thermal maturity zones suitable for oil or gas generation in western Orphan Basin and beneath the continental slopes.

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7

Dérerová, Jana, Miroslav Bielik, Igor Kohút y Dominika Godová. "Calculation of temperature distribution and rheological properties of the lithosphere along transect IV in the Western Carpathian-Pannonian Basin region". Contributions to Geophysics and Geodesy 49, n.º 4 (1 de diciembre de 2019): 497–510. http://dx.doi.org/10.2478/congeo-2019-0026.

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Abstract 2D integrated modelling algorithm was used to calculate the temperature distribution in the lithosphere along the transect IV located in the Western Carpathian-Pannonian Basin area. Based on the determined temperature field and given rheological parameters of the rocks, it was possible to calculate the strength distribution for both compressional and extensional regimes, construct the strength envelopes for chosen columns of the main tectonic units of the model, and thus construct a simple rheological model of the lithosphere along transect IV. The obtained results indicate decrease of the lithospheric strength from the European platform and the Western Carpathians towards the Pannonian Basin. The largest strength (valid for all tectonic units) can be observed within the upper crust with its maxima on the boundary between upper and lower crust, decreasing towards lower crust and disappearing in the lithospheric mantle, suggesting mostly rigid deformation occurring in the upper crust. A local increase in the values of strength can be observed in the eastern segment of the Western Carpathians where crustal thickening accompanies the lithospheric thickening (formation of the lithospheric root), unlike the previous models along transects I and II, that pass through the western segment of the Western Carpathians and their lithosphere-asthenosphere boundary is almost flat and therefore no accompanying crustal thickening is observed and the decrease in strength is slow and steady.

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8

Singh, Ramesh P., Q. Li y E. Nyland. "Lithospheric deformation beneath the Himalayan region". Physics of the Earth and Planetary Interiors 61, n.º 3-4 (enero de 1990): 291–96. http://dx.doi.org/10.1016/0031-9201(90)90112-b.

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9

Wu, Fu-Yuan, Jin-Hui Yang, Yi-Gang Xu, Simon A. Wilde y Richard J. Walker. "Destruction of the North China Craton in the Mesozoic". Annual Review of Earth and Planetary Sciences 47, n.º 1 (30 de mayo de 2019): 173–95. http://dx.doi.org/10.1146/annurev-earth-053018-060342.

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The North China Craton (NCC) was originally formed by the amalgamation of the eastern and western blocks along an orogenic belt at ∼1.9 Ga. After cratonization, the NCC was essentially stable until the Mesozoic, when intense felsic magmatism and related mineralization, deformation, pull-apart basins, and exhumation of the deep crust widely occurred, indicative of destruction or decratonization. Accompanying this destruction was significant removal of the cratonic keel and lithospheric transformation, whereby the thick (∼200 km) and refractory Archean lithosphere mantle was replaced by a thin (<80 km) juvenile one. The decratonization of the NCC was driven by flat slab subduction, followed by a rollback of the paleo-Pacific plate during the late Mesozoic. A global synthesis indicates that cratons are mainly destroyed by oceanic subduction, although mantle plumes might also trigger lithospheric thinning through thermal erosion. Widespread crust-derived felsic magmatism and large-scale ductile deformation can be regarded as petrological and structural indicators of craton destruction. ▪ A craton, a kind of ancient continental block on Earth, was formed mostly in the early Precambrian (>1.8 Ga). ▪ A craton is characterized by a rigid lithospheric root, which provides longevity and stability during its evolutionary history. ▪ Some cratons, such as the North China Craton, can be destroyed by losing their stability, manifested by magmatism, deformation, earthquake, etc.

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10

Dombrádi, Endre, Dimitrios Sokoutis, Gábor Bada, Sierd Cloetingh y Frank Horváth. "Modelling recent deformation of the Pannonian lithosphere: Lithospheric folding and tectonic topography". Tectonophysics 484, n.º 1-4 (marzo de 2010): 103–18. http://dx.doi.org/10.1016/j.tecto.2009.09.014.

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11

Byrne, Paul K., Richard C. Ghail, A. M. Celâl Şengör, Peter B. James, Christian Klimczak y Sean C. Solomon. "A globally fragmented and mobile lithosphere on Venus". Proceedings of the National Academy of Sciences 118, n.º 26 (21 de junio de 2021): e2025919118. http://dx.doi.org/10.1073/pnas.2025919118.

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Venus has been thought to possess a globally continuous lithosphere, in contrast to the mosaic of mobile tectonic plates that characterizes Earth. However, the Venus surface has been extensively deformed, and convection of the underlying mantle, possibly acting in concert with a low-strength lower crust, has been suggested as a source of some surface horizontal strains. The extent of surface mobility on Venus driven by mantle convection, however, and the style and scale of its tectonic expression have been unclear. We report a globally distributed set of crustal blocks in the Venus lowlands that show evidence for having rotated and/or moved laterally relative to one another, akin to jostling pack ice. At least some of this deformation on Venus postdates the emplacement of the locally youngest plains materials. Lithospheric stresses calculated from interior viscous flow models consistent with long-wavelength gravity and topography are sufficient to drive brittle failure in the upper Venus crust in all areas where these blocks are present, confirming that interior convective motion can provide a mechanism for driving deformation at the surface. The limited but widespread lithospheric mobility of Venus, in marked contrast to the tectonic styles indicative of a static lithosphere on Mercury, the Moon, and Mars, may offer parallels to interior–surface coupling on the early Earth, when global heat flux was substantially higher, and the lithosphere generally thinner, than today.

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12

Larionov, Igor, Evgeny Malkin y Vladimir Uvarov. "Deformation-Electromagnetic Relations in Lithospheric Activity Manifestations". E3S Web of Conferences 62 (2018): 03002. http://dx.doi.org/10.1051/e3sconf/20186203002.

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It has been shown that dipole radiation of accelerated charges, described by Larmor relation, is the basis of the known mechanic-electromagnetic processes of rock deformation. Comparison of crust deformation acceleration with natural electromagnetic field parameters of ELF-VLF range showed good relation. It manifests in the maxima of occurrence frequency density of synchronous deformation-electromagnetic events on two dimensional histograms. The data of a laser strain-meter and a recorder of natural electromagnetic radiation of ELF-VLF range, recorded in a zone of increased seismic activity (Kamchatka, Karymshina site), were used. The authors made an assumption on the existence of stationary regions of deformation process and mechanic-electromagnetic transformations corresponding to regions with different mechanic properties and rock petrographic composition.

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13

Pandey, O. P. y P. K. Agrawal. "Lithospheric Mantle Deformation beneath the Indian Cratons". Journal of Geology 107, n.º 6 (noviembre de 1999): 683–92. http://dx.doi.org/10.1086/314373.

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14

Liu, Han-Shou. "Deformation and Instability of Underthrusting Lithospheric Plates". Geophysical Journal of the Royal Astronomical Society 35, n.º 1-3 (15 de septiembre de 2009): 185–93. http://dx.doi.org/10.1111/j.1365-246x.1973.tb02421.x.

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15

Dong, Xingpeng, Dinghui Yang y Hejun Zhu. "Adjoint Tomography of the Lithospheric Structure beneath Northeastern Tibet". Seismological Research Letters 91, n.º 6 (23 de septiembre de 2020): 3304–12. http://dx.doi.org/10.1785/0220200135.

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Abstract Northeastern Tibet is still in the primary stage of tectonic deformation and is the key area for studying the lateral expansion of the Tibetan plateau. In particular, the existence of lower crustal flow, southward subduction of the Asian lithosphere, and northward subduction of the Indian lithosphere beneath northeastern Tibet remains controversial. To provide insights into these issues, a high-resolution 3D radially anisotropic model of the lithospheric structure of northeastern Tibet is developed based on adjoint tomography. The Tibetan plateau is characterized as a low S-wave velocity lithosphere, in contrast with the relatively high S-wave velocities of the stable Asian blocks. Our tomographic result indicates that the low-velocity zone (LVZ) within the deep crust extends northeastward from Songpan–Ganzi to Qilian, which is interpreted as a channel flow within the crust. The upper mantle of Alxa and Qinling–Qilian are dominated by a rather homogeneous LVZ, which is inconsistent with the hypothesis that the Asian lithospheric mantle is being subducted southward beneath northeastern Tibet. Furthermore, high-velocity regions are observed in the southern Songpan–Ganzi region at depths ranging from 100 to 200 km, indicating that the northward-subducting Indian plate has probably reached the Xianshuihe fault.

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16

Clowes, Ron M., Don J. White y Zoltan Hajnal. "Mantle heterogeneities and their significance: results from Lithoprobe seismic reflection and refraction – wide-angle reflection studiesThis 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.Lithoprobe Contribution 1486." Canadian Journal of Earth Sciences 47, n.º 4 (abril de 2010): 409–43. http://dx.doi.org/10.1139/e10-009.

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Within Lithoprobe’s 10 transects, data from more than 20 000 km of multichannel seismic (MCS) reflection profiling and 12 refraction – wide-angle reflection (R/WAR) surveys were acquired. While the main results related to crustal structure, the data also indicated substantial heterogeneity in the lithospheric mantle. Images of fossilized subduction zones from the Eocene to the Neoarchean demonstrate that current plate tectonic processes have been active for more than 2.6 Ga. The Canadian Cordillera has a thin (50–60 km) lithosphere that is likely receiving some dynamic support from the asthenosphere below. Vestiges of the last stage of accretionary tectonic processes that formed the Archean Superior craton are indicated by an unusual anisotropic high velocity layer that may represent relic oceanic lithosphere. Within the Paleoproterozoic Trans-Hudson Orogen, a restricted region of upper mantle P-wave velocity anisotropy is identified with the continental collision between the bounding Hearne and Superior cratons. In the Archean Hearne and Wyoming provinces, two dipping structures within the sub-crustal lithosphere are interpreted as subduction features related to the assembly of the two cratons. Finite-difference modeling of long-offset data (over 1300 km) reveals fine-scale heterogeneities within a layer between 90 and 150 km in the continental lithosphere, perhaps formed through lateral flow or deformation within the upper mantle. Based on Lithoprobe data, heterogeneities within the lithospheric mantle are reasonably common. They have a wide range of seismic signatures, include many different types and show differing scales. Nevertheless, their extent in the lithospheric mantle is considerably less than in the crust.

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17

Tavani, S. "Plate kinematics in the Cantabrian domain of the Pyrenean orogen". Solid Earth 3, n.º 2 (3 de septiembre de 2012): 265–92. http://dx.doi.org/10.5194/se-3-265-2012.

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Abstract. The Cantabrian domain represents the western portion of the Pyrenean orogen, in the area where the Iberian continental lithosphere was subducted toward the north underneath the transitional to oceanic lithosphere of the Bay of Biscay. There, the about 100 km of orogenic convergence have been mostly accommodated in the northern portion of the orogen (i.e. the retro wedge) developed in the Bay of Biscay abyssal plain, while only crustal-scale folding with limited internal deformation occurred in the Cantabrian southern wedge (pro-wedge). Integrated meso- and macrostructural analyses and a reappraisal of available information from the transitional area between the Pyrenean and Cantabrian domains are presented in this work, allowing to set geometric and kinematic constraints on the entire Meso-Cenozoic history of the northern portion of the Iberian Plate, including subduction initiation and evolution in the western portion of the Pyrenean orogen. The structural record of the Late Jurassic to Early Cretaceous deformation stage, which was associated with rifting and seafloor spreading in the Bay of Biscay, indicates a ridge perpendicular (NNE-SSW oriented) extension, with no evidence of relevant strike-slip components during rifting. A Cenozoic NNW-SSE oriented shortening stage followed, related to the limited (about 100 km) north-directed subduction of the Iberian continental lithosphere underneath the transitional to oceanic lithosphere of the Bay of Biscay. Subduction led to the formation of the poorly-developed Cantabrian pro-wedge, which is laterally juxtaposed to the well-developed Pyrenean pro-wedge to the east. During this convergence stage, the structural framework in the Cantabrian pro-wedge, and particularly along its transition with the Pyrenean wedge to the east, was severely complicated by the reactivation of Paleozoic and Mesozoic inherited structures. Data presented in this work fully support the development of the Cantabrian Mountains as related to indentation and consequent thickening of the Bay of Biscay transitional lower crust during north-directed subduction of Iberian continental lithosphere. In essence, the Cantabrian pro-wedge is a lithospheric south-verging fault-propagation anticline developing above the subduction plane. The structural record in the area indicates that a lithospheric fault-propagation folding stage was predated, during the very early stages of orogenic shortening, by the development of a lithospheric-scale open syncline overlying the nucleation point of lithosphere sinking. Such a syncline is today partially preserved and represents one of the few natural examples of subduction initiation.

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Osei Tutu, Anthony, Bernhard Steinberger, Stephan V. Sobolev, Irina Rogozhina y Anton A. Popov. "Effects of upper mantle heterogeneities on the lithospheric stress field and dynamic topography". Solid Earth 9, n.º 3 (16 de mayo de 2018): 649–68. http://dx.doi.org/10.5194/se-9-649-2018.

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Abstract. The orientation and tectonic regime of the observed crustal/lithospheric stress field contribute to our knowledge of different deformation processes occurring within the Earth's crust and lithosphere. In this study, we analyze the influence of the thermal and density structure of the upper mantle on the lithospheric stress field and topography. We use a 3-D lithosphere–asthenosphere numerical model with power-law rheology, coupled to a spectral mantle flow code at 300 km depth. Our results are validated against the World Stress Map 2016 (WSM2016) and the observation-based residual topography. We derive the upper mantle thermal structure from either a heat flow model combined with a seafloor age model (TM1) or a global S-wave velocity model (TM2). We show that lateral density heterogeneities in the upper 300 km have a limited influence on the modeled horizontal stress field as opposed to the resulting dynamic topography that appears more sensitive to such heterogeneities. The modeled stress field directions, using only the mantle heterogeneities below 300 km, are not perturbed much when the effects of lithosphere and crust above 300 km are added. In contrast, modeled stress magnitudes and dynamic topography are to a greater extent controlled by the upper mantle density structure. After correction for the chemical depletion of continents, the TM2 model leads to a much better fit with the observed residual topography giving a good correlation of 0.51 in continents, but this correction leads to no significant improvement of the fit between the WSM2016 and the resulting lithosphere stresses. In continental regions with abundant heat flow data, TM1 results in relatively small angular misfits. For example, in western Europe the misfit between the modeled and observation-based stress is 18.3°. Our findings emphasize that the relative contributions coming from shallow and deep mantle dynamic forces are quite different for the lithospheric stress field and dynamic topography.

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Petrescu, Laura, Graham Stuart, Gregory Houseman y Ian Bastow. "Upper mantle deformation signatures of craton–orogen interaction in the Carpathian–Pannonian region from SKS anisotropy analysis". Geophysical Journal International 220, n.º 3 (13 de enero de 2020): 2105–18. http://dx.doi.org/10.1093/gji/ggz573.

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SUMMARY Since the Mesozoic, central and eastern European tectonics have been dominated by the closure of the Tethyan Ocean as the African and European plates collided. In the Miocene, the edge of the East European Craton and Moesian Platform were reworked in collision during the Carpathian orogeny and lithospheric extension formed the Pannonian Basin. To investigate the mantle deformation signatures associated with this complex collisional-extensional system, we carry out SKS splitting analysis at 123 broad-band seismic stations in the region. We compare our measurements with estimates of lithospheric thickness and recent seismic tomography models to test for correlation with mantle heterogeneities. Reviewing splitting delay times in light of xenolith measurements of anisotropy yields estimates of anisotropic layer thickness. Fast polarization directions are mostly NW–SE oriented across the seismically slow West Carpathians and Pannonian Basin and are independent of geological boundaries, absolute plate motion direction or an expected palaeo-slab roll-back path. Instead, they are systematically orthogonal to maximum stress directions, implying that the indenting Adria Plate, the leading deformational force in Central Europe, reset the upper-mantle mineral fabric in the past 5 Ma beneath the Pannonian Basin, overprinting the anisotropic signature of earlier tectonic events. Towards the east, fast polarization directions are perpendicular to steep gradients of lithospheric thickness and align along the edges of fast seismic anomalies beneath the Precambrian-aged Moesian Platform in the South Carpathians and the East European Craton, supporting the idea that craton roots exert a strong influence on the surrounding mantle flow. Within the Moesian Platform, SKS measurements become more variable with Fresnel zone arguments indicating a shallow fossil lithospheric source of anisotropy likely caused by older tectonic deformation frozen in the Precambrian. In the Southeast Carpathian corner, in the Vrancea Seismic Zone, a lithospheric fragment that sinks into the mantle is sandwiched between two slow anomalies, but smaller SKS delay times reveal weaker anisotropy occurs mainly to the NW side, consistent with asymmetric upwelling adjacent to a slab, slower mantle velocities and recent volcanism.

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20

Fernández-Lozano, J., G. Gutiérrez-Alonso, E. Willingshofer, D. Sokoutis, G. de Vicente y S. Cloetingh. "Shaping of intraplate mountain patterns: The Cantabrian orocline legacy in Alpine Iberia". Lithosphere 11, n.º 5 (2 de agosto de 2019): 708–21. http://dx.doi.org/10.1130/l1079.1.

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Abstract The present-day topography in Iberia is related to geodynamic processes dealing with lithospheric-scale deformation. However, little attention has been paid to the role of inherited crustal- or lithospheric-scale structures involved in the recent observed large-scale topographic patterns. Whereas the analysis of brittle structures focuses on the evolution of Mesozoic sedimentary basins and their subsequent response to tectonic inversion, their contribution to mountain building has been underestimated. Large numbers of structures, from ductile to brittle, which affected the whole lithosphere, were developed during the evolution of the Cantabrian orocline (ca. 310–300 Ma). The contribution of these Paleozoic post-Variscan structures, together with lithospheric mantle evolution and replacement during orocline development in the Mesozoic and Cenozoic geological evolution of Iberia, remains unexplored. To explore the role of these inherited structures on the final configuration of topography during N-S Pyrenean shortening, we carried out a series of analogue experiments complemented by surface velocity field analyses. Our experiments indicate that strain was concentrated along preexisting crustal- to lithospheric-scale discontinuities, and they show several reactivation events marked by differences in the velocity vector field. Differences in fault displacement were also observed in the models depending upon preexisting fault trends. The obtained results may explain the different amount of displacement observed during the reactivation of some of the post-orocline structures in Iberia during the Cenozoic, indicating the key role of unveiled structures, which probably have accommodated most of the Alpine shortening.

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Jaquet, Yoann, Thibault Duretz y Stefan M. Schmalholz. "Dramatic effect of elasticity on thermal softening and strain localization during lithospheric shortening". Geophysical Journal International 204, n.º 2 (11 de diciembre de 2015): 780–84. http://dx.doi.org/10.1093/gji/ggv464.

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Abstract We present two-dimensional numerical simulations for shortening a viscoelastoplastic lithosphere to quantify the impact of elasticity on strain localization due to thermal softening. The model conserves energy and mechanical work is converted into heat or stored as elastic strain energy. For a shear modulus G = 1010 Pa, a prominent lithospheric shear zone forms and elastic energy release increases the localization intensity (strain rate amplification). For G = 5 × 1010 Pa shear zones still form but deformation is less localized. For G = 1012 Pa, the lithosphere behaves effectively viscoplastic and no shear zones form during homogeneous thickening. Maximal shearing-related increase of surface heat flux is 15–25 mW m−2 and of temperature at lower crustal depth is ∼150 °C, whereby these peak values are transient (0.1–1 My). Elasticity and related energy release can significantly contribute to strain localization and plate-like behaviour of the lithosphere required for plate tectonics.

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22

MacDougall, Malcolm D. J., Alexander Braun y Georgia Fotopoulos. "Evidence of Lithospheric Boudinage in the Grand Banks of Newfoundland from Geophysical Observations". Geosciences 11, n.º 2 (28 de enero de 2021): 55. http://dx.doi.org/10.3390/geosciences11020055.

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The evolution of the passive margin off the coast of Eastern Canada has been characterized by a series of rifting episodes which caused widespread extension of the lithosphere and associated structural anomalies, some with the potential to be classified as a result of lithospheric boudinage. Crustal thinning of competent layers is often apparent in seismic sections, and deeper Moho undulations may appear as repeating elongated anomalies in gravity and magnetic surveys. By comparing the similar evolutions of the Grand Banks and the Norwegian Lofoten-Vesterålen passive margins, it is reasonable to explore the potential of the same structures being present. This investigation supplements our knowledge of analogous examples in the Norwegian Margin and the South China Sea with a thorough investigation of seismic, gravity and magnetic signatures, to determine that boudinage structures are evident in the context of the Grand Banks. Through analysis of geophysical data (including seismic, gravity and magnetic observations), a multi-stage boudinage mechanism is proposed, which is characterized by an upper crust short-wavelength deformation ranging from approximately 20–80 km and a lower crust long-wavelength deformation exceeding 200 km in length. In addition, the boudinage mechanism caused slightly different structures which are apparent in the block geometry and layeredness. Based on these results, there are indications that boudinage wavelength increases with each successive rifting phase, with geometry changing from domino style to a more shearband/symmetrical style as the scale of deformation is increased to include the entire lithosphere.

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Zaporozan, Taras, Andrew W. Frederiksen, Alexey Bryksin y Fiona Darbyshire. "Surface-wave images of western Canada: lithospheric variations across the Cordillera–craton boundary". Canadian Journal of Earth Sciences 55, n.º 8 (agosto de 2018): 887–96. http://dx.doi.org/10.1139/cjes-2017-0277.

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Two-station surface-wave analysis was used to measure Rayleigh-wave phase velocities between 105 station pairs in western Canada, straddling the boundary between the tectonically active Cordillera and the adjacent stable craton. Major variations in phase velocity are seen across the boundary at periods from 15 to 200 s, periods primarily sensitive to upper mantle structure. Tomographic inversion of these phase velocities was used to generate phase velocity maps at these periods, indicating a sharp contrast between low-velocity Cordilleran upper mantle and high-velocity cratonic lithosphere. Depth inversion along selected transects indicates that the Cordillera–craton upper mantle contact varies in dip along the deformation front, with cratonic lithosphere of the Taltson province overthrusting Cordilleran asthenosphere in the northern Cordillera, and Cordilleran asthenosphere overthrusting Wopmay lithosphere further south. Localized high-velocity features at sub-lithospheric depths beneath the Cordillera are interpreted as Farallon slab fragments, with the gap between these features indicating a slab window. A high-velocity feature in the lower lithosphere of the Slave province may be related to Proterozic or Archean subduction.

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Jing, Z., F. Bihong, S. Pilong y G. Qiang. "INVESTIGATION OF LITHOSPHERIC STRUCTURE IN MONGOLIA: INSIGHTS FROM INSAR OBSERVATIONS AND MODELLING". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W7 (13 de septiembre de 2017): 609–16. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w7-609-2017.

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The western Mongolia is a seismically active intracontinental region, with ongoing tectonic deformation and widespread seismicity related to the far-field effects of India-Eurasia collision. During the 20th century, four earthquakes with the magnitude larger than 8 occurred in the western Mongolia and its surrounding regions, providing a unique opportunity to study the geodynamics of intracontinental tectonic deformations. The 1957 magnitude 8.3 Gobi-Altai earthquake is one of the largest seismic events. The deformation pattern of rupture zone associated with this earthquake is complex, involving left-lateral strike-slip and reverse dip-slip faulting on several distinct geological structures in a 264&thinsp;×&thinsp;40&thinsp;km wide zone. To understand the relationship between the observed postseismic surface deformation and the rheological structure of the upper lithosphere, Interferometric Synthetic Aperture Radar (InSAR) data are used to study the 1957 earthquake. Then we developed a postseismic model in a spherical, radially layered elastic-viscoelastic Earth based on InSAR results, and further analysed the dominant contribution to the surface deformation. This work is important for understanding not only the regional tectonics, but also the structure and dynamics of the lithosphere. <br><br> SAR data were acquired from the ERS1/2 and Envisat from 1996 to 2010. Using the Repeat Orbit Interferometry Package (ROI_PAC), 124 postseismic interferograms are produced on four adjacent tracks. By stacking these interferograms, the maximum InSAR line-of-sight deformation rate along the Gobi-Altai fault zone is obtained. The main results are as follows: (1) The maximum InSAR line-of-sight deformation velocity along this large fault zone is about 6&thinsp;mm/yr; (2) The modelled surface deformation suggests that the viscoelastic relaxation is the most reasonable mechanism to explain the observed surface motion; (3) The optimal model cover the Gobi-Altai seismogenic thickness is 10&thinsp;km; (4) The lower bound of Maxwell viscosity of lower crust and upper mantle is approximately 9&thinsp;×&thinsp;10<sup>19</sup>&thinsp;Pa&thinsp;s, and the Maxwell relaxation time corresponding to this viscosity is 95.13 years.

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25

Keep, Myra. "Models of lithospheric-scale deformation during plate collision: effects of indentor shape and lithospheric thickness." Tectonophysics 326, n.º 3-4 (noviembre de 2000): 203–16. http://dx.doi.org/10.1016/s0040-1951(00)00123-2.

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26

Larionov, Igor, Yuriy Marapulets y Mikhail Mishchenko. "Results of atmospheric-lithospheric observations of acoustic radiation in Kamchatka". E3S Web of Conferences 127 (2019): 02023. http://dx.doi.org/10.1051/e3sconf/201912702023.

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Simultaneous atomspheric-lithospheric acoustic observations have been carried out during autumn-spring periods of 2017-2019 in Kamchatka at “Karymshina” observation site located in the zone of different-rank tectonic faults. A laser strainmeter-interferometer, a seismoacoustic receiver and a microbarometer were installed to realize the observations. It was detected that during deformation disturbances, geoacoustic signals are generated in rocks with relative deformations of 10-5 – 10-7 at the place of recording. These signals pass the Earth-atmosphere boundary and are recorded in the air by the ground surface.

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27

Singh, Harshpal y Rezene Mahatsente. "Lithospheric Structure of Eastern Tibetan Plateau from Terrestrial and Satellite Gravity Data Modeling: Implication for Asthenospheric Underplating". Lithosphere 2020, n.º 1 (1 de septiembre de 2020): 1–19. http://dx.doi.org/10.2113/2020/8897964.

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Abstract The lithosphere of the eastern Tibetan plateau is underlain by a low-velocity zone at shallow depths which is interpreted as asthenospheric material in the upper-most mantle in various seismic tomography studies. The driving mechanism for the presence of asthenospheric material in the upper-most mantle is not well understood, and the spatial extent of the asthenospheric material is not well delineated. We use 2.5D gravity models to assess what drove the asthenospheric flow upwards in the past and determine the lateral extent of the asthenospheric material in the upper-most mantle. The models also allow us to determine the Indian slab configuration below the Tibetan plateau. The gravity models show that lithospheric thickness increases from ~120 km in the central and eastern parts of the plateau to ~150 km in the west, indicating that the lithosphere in the central and eastern parts of the plateau may have been delaminated. The ~30 km shallower Lithosphere-Asthenosphere Boundary in the central and eastern Tibetan plateau may indicate that asthenospheric flow could have been induced in the past by a combination of lithospheric delamination and a slab break-off event of the Greater Indian slab. The spatial extent of the asthenospheric material in the upper-most mantle beneath the Tibetan plateau is ~15,000 km2 (N−S length=500 km and thickness=30 km) between 85°E and 88°E, which could even extend east of 92°E. The Indian slab is dipping more steeply in the east. The slab dip along the Indian plate increases from ~10° in the west to ~18° in the central (~87°E) and ~25° in the eastern part (~91°E) of the plateau, indicating that the style of lithospheric deformation changes from underthrusting to slab roll-back from west to east.

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28

Sandiford, Mike, John Foden, Shaohua Zhou y Simon Turner. "Granite genesis and the mechanics of convergent orogenic belts with application to the southern Adelaide Fold Belt". Earth and Environmental Science Transactions of the Royal Society of Edinburgh 83, n.º 1-2 (1992): 83–93. http://dx.doi.org/10.1017/s026359330000777x.

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ABSTRACTTwo models for the heating responsible for granite generation during convergent deformation may be distinguished on the basis of the length- and time-scales associated with the thermal perturbation, namely: (1) long-lived, lithospheric-scale heating as a conductive response to the deformation, and (2) transient, localised heating as a response to advective heat sources such as mantle-derived melts. The strong temperature dependence of lithospheric rheology implies that the heat advected within rising granites may affect the distribution and rates of deformation within the developing orogen in a way that reflects the thermal regime attendant on granite formation; this contention is supported by numerical models of lithospheric deformation based on the thin-sheet approximation. The model results are compared with geological and isotopic constraints on granite genesis in the southern Adelaide Fold Belt where intrusion spans a 25 Ma convergent deformation cycle, from about 516 to 490 Ma, resulting in crustal thickening to 50–55 km. High-T metamorphism in this belt is spatially restricted to an axis of magmatic activity where the intensity and complexity of deformation is significantly greater, and may have started earlier, than in adjacent low-grade areas. The implication is that granite generation and emplacement is a causative factor in localising deformation, and on the basis of the results of the mechanical models suggests that granite formation occurred in response to localised, transient crustal heating by mantle melts. This is consistent with the Nd- and Sr-isotopic composition of the granites which seems to reflect mixed sources with components derived both from the depleted contemporary mantle and the older crust.

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29

Singh, Sarva Jit y Sunita Rani. "Lithospheric Deformation Associated with Two-Dimensional Strike-Slip Faulting." Journal of Physics of the Earth 42, n.º 3 (1994): 197–220. http://dx.doi.org/10.4294/jpe1952.42.197.

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30

Dayem, Katherine E., Peter Molnar, Marin K. Clark y Gregory A. Houseman. "Far-field lithospheric deformation in Tibet during continental collision". Tectonics 28, n.º 6 (diciembre de 2009): n/a. http://dx.doi.org/10.1029/2008tc002344.

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31

Samae, Vahid, Patrick Cordier, Sylvie Demouchy, Caroline Bollinger, Julien Gasc, Sanae Koizumi, Alexandre Mussi, Dominique Schryvers y Hosni Idrissi. "Stress-induced amorphization triggers deformation in the lithospheric mantle". Nature 591, n.º 7848 (3 de marzo de 2021): 82–86. http://dx.doi.org/10.1038/s41586-021-03238-3.

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32

White, Joseph Clancy y Christopher K. Mawer. "Deep-crustal deformation textures along megathrusts from Newfoundland and Ontario: implications for microstructural preservation, strain rates, and strength of the lithosphere". Canadian Journal of Earth Sciences 29, n.º 2 (1 de febrero de 1992): 328–37. http://dx.doi.org/10.1139/e92-029.

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Lithospheric-scale thrusts from the west Newfoundland ophiolite belt (White Hills Peridotite shear zone) and the south-western Grenville Province (Parry Sound shear zone) involve rocks of lower crustal and (or) upper mantle origin that exhibit intense crystal-plastic deformation of plagioclase, K-feldspar, orthopyroxene, and clinopyroxene, minerals that are commonly viewed as representative of low-ductility phases. The occurrence of this extreme deformation in shear zones that exhibit similar lower crustal syntectonic P–T conditions suggests a phenomenological link between the megathrust environment and both the generation and subsequent preservation of the observed deformation microstructures. An empirical homologous parameter is constructed in an attempt to characterize conditions for similar behaviour among different minerals and to explore the feasibility of refining a threshold recovery–preservation condition within the megathrusts studied. This parameter predicts, at the estimated syntectonic temperature of 800 °C, the similarity of microstructures in highly strained albite and orthopyroxene crystals observed in both megathrusts. This temperature is interpreted as a lower limit for the upper threshold of microstructure preservation in albite and orthopyroxene for the particular megathrust history. Comparison of tectonic constraints with strain rates calculated at the inferred threshold temperature for several minerals with tectonic constraints indicates that strain rates of at least 10−12 s−1 are both rheologically possible and geometrically plausible in shear zones of kilometre-scale widths. The associated lithosphere strength during megathrust displacement is on the order of 1–50 MPa. These data support formation of synkinematic records within shear zones that preserve evidence of lithospheric behaviour over crustal-thickness length scales.

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33

Sadeghi-Bagherabadi, Amir, Farhad Sobouti, Abdolreza Ghods, Khalil Motaghi, Morteza Talebian, Ling Chen, Mingming Jiang, Yinshuang Ai y Yumei He. "Upper mantle anisotropy and deformation beneath the major thrust-and-fold belts of Zagros and Alborz and the Iranian Plateau". Geophysical Journal International 214, n.º 3 (14 de junio de 2018): 1913–18. http://dx.doi.org/10.1093/gji/ggy233.

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SUMMARY We present new SKS splitting measurements obtained from a temporary seismic broad-band network in western Iran across the Arabia–Eurasia collision zone. The average delay time over the entire network was found to be 1.27 ± 0.27 s. In the Zagros where the lithosphere attains its greatest thickness, the fast-axes are predominantly subparallel to the trend of the mountain ranges, suggesting a lithospheric origin of the anisotropy caused by transpressional deformation. In contrast in the Alborz, the fast-axes become subparallel to the absolute plate motion vectors and we propose that anisotropy is mainly controlled by the direction of the asthenospheric flow field. The central Iran region shows a more complex pattern of anisotropy that could be the result of variable and small-scale deformation fields in the crust and the shallow sublithospheric mantle.

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34

Mussi, Alexandre, Maula Nafi, Sylvie Demouchy y Patrick Cordier. "On the deformation mechanism of olivine single crystals at lithospheric temperatures: an electron tomography study". European Journal of Mineralogy 27, n.º 6 (14 de diciembre de 2015): 707–15. http://dx.doi.org/10.1127/ejm/2015/0027-2481.

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35

Parizot, Oriane, Yves Missenard, Pierre Vergely, Frederic Haurine, Aurélie Noret, Guillaume Delpech, Jocelyn Barbarand y Philippe Sarda. "Tectonic Record of Deformation in Intraplate Domains: Case Study of Far-Field Deformation in the Grands Causses Area, France". Geofluids 2020 (15 de julio de 2020): 1–19. http://dx.doi.org/10.1155/2020/7598137.

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Although tectonic plates are usually considered as rigid blocks, intraplate deformation such as lithospheric buckling or diffuse brittle deformation has been recognized for a long time. However, the origin of these deformations remains puzzling. Indeed, whereas the chronology of deformation at plate boundaries can be constrained by numerous methods (syntectonic sedimentary record, thermochronology, etc.), dating of brittle structures (faults, veins, and joints) in the far-field domains remains challenging, preventing a global interpretation of the system as a whole. In this contribution, we have combined a tectonic study with a synkinematical geochronological study of fault-related calcites of the Grands Causses intraplate domain, north of the Pyrenean orogeny. We show that these faults record a much longer history of deformation than previously thought. The Mesozoic extension, usually attributed to an early Jurassic Tethysian rifting event, probably lasted until the Barremian-Aptian epoch, in response to the Pyrenean basin’s opening. The so-called “Pyrenean deformation” of the Grands Causses domain, usually associated with the paroxysm of deformation in the belt during the late Eocene, began much earlier, around 100 Ma, and lasted for more than 60-70 Ma. This study demonstrates the high sensitivity of an intraplate domain (Grands Causses area) to record extensional or compressional deformations occurring at the edge of neighbouring plates.

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36

Granet, Michel, Sebastien Judenherc y Annie Souriau. "Des images du systeme lithosphere-asthenosphere sous la France et leurs implications geodynamiques; l'apport de la tomographie telesismique et de l'anisotropie sismique". Bulletin de la Société Géologique de France 171, n.º 2 (1 de marzo de 2000): 149–67. http://dx.doi.org/10.2113/171.2.149.

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Abstract From seismic tomography and seismic anisotropy, images of the lithosphere-asthenosphere system beneath France for some remarkable tectonic areas have been computed : a continental rift system (the Upper Rhinegraben), an Hercynian structure reactivated by Neogene volcanism (Massif central), a region of a recent continental collision (Pyrenees) and finally a region of an ancient orogeny (Armorican Massif). These images have a horizontal spatial resolution of the order of 10 km and show not only the geometry of the deep geological structures but will also illustrate the link between surface observations and structures detected at depth. The images demonstrate the passive character of the Rhinegraben mainly because no low-velocity was found below the Moho, show the presence of a thermal anomaly beneath the Massif central interpreted as caused by a mantle plume in the decaying phase of its evolution and prove the lithospheric scale of the North Pyrenean fault and of the South-Armorican shear zone. The anisotropic measurements suggest a lithospheric deformation related to the most recent tectonic event. In the Pyrenees, the Armorican Massif or the Rhinegraben areas, the directions of the fast-polarisation azimuth (the polarisation direction of the fast shear wave) are parallel to the tectonic texture of the last events, but suggest also a reactivation of inherited Hercynian discontinuities. In the Massif central, the splitting parameters distinguish between two lithospheric units regions marked by a distinct fast-polarisation azimuth on each side of the Sillon Houiller fault zone.

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37

Telyatnikov, Ilya. "Modeling of deformation processes in lithospheric structures during their static interaction". Thermal Science 23, Suppl. 2 (2019): 591–97. http://dx.doi.org/10.2298/tsci19s2591t.

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We consider a model of lithospheric structures contacting along rectilinear geological faults as a system of composite plates on an elastic foundation. A simplification of the block element method for different-sized blocks is proposed. We also describe an approach that is a modification of the block element method using the method of eigenfunctions. The method is considered on the example of a static interaction problem of extended plates on the surface of an elastic layer for a given surface load. As a result we obtain the representations of solutions describing the surface displacements. The application of the proposed approach will allow us to draw conclusions about the effect of the physical and mechanical properties of lithospheric structures and the type of fault on the nature of displacements in the geological environment which are applicable for studying the structure of faults in the upper part of the earth's crust.

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38

Jiménez-Munt, Ivone, Daniel Garcia-Castellanos y Manel Fernandez. "Thin-sheet modelling of lithospheric deformation and surface mass transport". Tectonophysics 407, n.º 3-4 (octubre de 2005): 239–55. http://dx.doi.org/10.1016/j.tecto.2005.08.015.

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39

Frets, Erwin, Andréa Tommasi, Carlos J. Garrido, José Alberto Padrón-Navarta, Isma Amri y Kamal Targuisti. "Deformation processes and rheology of pyroxenites under lithospheric mantle conditions". Journal of Structural Geology 39 (junio de 2012): 138–57. http://dx.doi.org/10.1016/j.jsg.2012.02.019.

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40

YI, Gui-Xi, Hua-Jian YAO, Jie-Shou ZHU y Robert D. van der Hilst. "Lithospheric Deformation of Continental China from Rayleigh Wave Azimuthal Anisotropy". Chinese Journal of Geophysics 53, n.º 1 (enero de 2010): 121–35. http://dx.doi.org/10.1002/cjg2.1479.

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41

Deng, Yangfan y Will Levandowski. "Lithospheric Alteration, Intraplate Crustal Deformation, and Topography in Eastern China". Tectonics 37, n.º 11 (noviembre de 2018): 4120–34. http://dx.doi.org/10.1029/2018tc005079.

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42

Goodwillie, Andrew M. y Barry Parsons. "Placing bounds on lithospheric deformation in the central Pacific Ocean". Earth and Planetary Science Letters 111, n.º 1 (junio de 1992): 123–39. http://dx.doi.org/10.1016/0012-821x(92)90174-t.

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43

Gordon, Richard G. "Lithospheric Deformation in the equatorial Indian Ocean: Timing and Tibet". Geology 37, n.º 3 (marzo de 2009): 287–88. http://dx.doi.org/10.1130/focus032009.1.

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44

Bendick, R. y L. Flesch. "Reconciling lithospheric deformation and lower crustal flow beneath central Tibet". Geology 35, n.º 10 (2007): 895. http://dx.doi.org/10.1130/g23714a.1.

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45

Ernst, W. G., Norman H. Sleep y Tatsuki Tsujimori. "Plate-tectonic evolution of the Earth: bottom-up and top-down mantle circulation". Canadian Journal of Earth Sciences 53, n.º 11 (noviembre de 2016): 1103–20. http://dx.doi.org/10.1139/cjes-2015-0126.

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Intense devolatilization and chemical-density differentiation attended accretion of planetesimals on the primordial Earth. These processes gradually abated after cooling and solidification of an early magma ocean. By 4.3 or 4.2 Ga, water oceans were present, so surface temperatures had fallen far below low-pressure solidi of dry peridotite, basalt, and granite, ∼1300, ∼1120, and ∼950 °C, respectively. At less than half their T solidi, rocky materials existed as thin lithospheric slabs in the near-surface Hadean Earth. Stagnant-lid convection may have occurred initially but was at least episodically overwhelmed by subduction because effective, massive heat transfer necessitated vigorous mantle overturn in the early, hot planet. Bottom-up mantle convection, including voluminous plume ascent, efficiently rid the Earth of deep-seated heat. It declined over time as cooling and top-down lithospheric sinking increased. Thickening and both lateral extensional + contractional deformation typified the post-Hadean lithosphere. Stages of geologic evolution included (i) 4.5–4.4 Ga, magma ocean overturn involved ephemeral, surficial rocky platelets; (ii) 4.4–2.7 Ga, formation of oceanic and small continental plates were obliterated by return mantle flow prior to ∼4.0 Ga; continental material gradually accumulated as largely sub-sea, sialic crust-capped lithospheric collages; (iii) 2.7–1.0 Ga, progressive suturing of old shields + younger orogenic belts led to cratonal plates typified by emerging continental freeboard, increasing sedimentary differentiation, and episodic glaciation during transpolar drift; onset of temporally limited stagnant-lid mantle convection occurred beneath enlarging supercontinents; (iv) 1.0 Ga–present, laminar-flowing asthenospheric cells are now capped by giant, stately moving plates. Near-restriction of komatiitic lavas to the Archean, and appearance of multicycle sediments, ophiolite complexes ± alkaline igneous rocks, and high-pressure–ultrahigh-pressure (HP–UHP) metamorphic belts in progressively younger Proterozoic and Phanerozoic orogens reflect increasing negative buoyancy of cool oceanic lithosphere, but decreasing subductability of enlarging, more buoyant continental plates. Attending supercontinental assembly, density instabilities of thickening oceanic plates began to control overturn of suboceanic mantle as cold, top-down convection. Over time, the scales and dynamics of hot asthenospheric upwelling versus lithospheric foundering + mantle return flow (bottom-up plume-driven ascent versus top-down plate subduction) evolved gradually, reflecting planetary cooling. These evolving plate-tectonic processes have accompanied the Earth’s thermal history since ∼4.4 Ga.

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46

Guillot, Stéphane y Anne Replumaz. "Importance of continental subductions for the growth of the Tibetan plateau". Bulletin de la Société Géologique de France 184, n.º 3 (1 de marzo de 2013): 199–223. http://dx.doi.org/10.2113/gssgfbull.184.3.199.

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Abstract How and when the Tibetan plateau developed has long been a puzzling question with implications for the current understanding of the behaviour of the continental lithosphere in convergent zones. We present and discuss recent data acquired in geology and geophysics and through igneous and metamorphic petrology and palaeo-altitude estimates. It appears from this research that Tibet initially resulted from the accretion of the Gondwana continental blocks to the southern Asian margin during the Palaeozoic and Mesozoic eras. These successive accretions have potentially favoured the creation of local landforms, particularly in southern Tibet, but no evidence exists in favour of the existence of a proto-Tibetan plateau prior to the Cenozoic. Moreover, before the India-Asia collision, the Tibetan crust had to be sufficiently cold and rigid to transfer the horizontal forces from India to northern Tibet and localize the deformation along the major strike-slip faults. However, these successive accretions associated with subductions have metasomatized the Tibetan lithospheric mantle and largely explain the potassium- and sodium-rich Cenozoic magmatism. Another consequence of this contamination by fluids is the softening of the Tibetan lithosphere, which favoured intra-continental subductions. The timing and the geochemical signatures of the magmatism and the palaeo-altitudes suggest the early growth of the Tibetan plateau. By the Eocene, the southern plateau and the northern portion of Himalaya would be at an altitude of approximately 4000 meters, while the central and northern Tibetan plateau was at altitudes of approximately 2000 to 3000 meters at the Eocene-Oligocene transition. From all of these data, we propose a model of the formation of the Tibetan plateau coupled with the formation of Himalaya, which accounts for more than 2500 km of convergence accommodated by the deformation of the continental lithospheres. During the early Eocene (55-45 Ma), the continental subduction of the high-strength Indian continental lithosphere dominates, ending with the detachment of the Indian slab. Between 45 and 35 Ma, the continental collision is established, resulting in the thickening of the internal Himalayan region and southern Tibet and the initiation of intra-tibetan subductions. By 35 Ma, the southward subduction of the intra-tibetan Songpan-Ganze terrane ends in slab break-off and is relayed by the oblique subduction of the Tarim the Athyn Tagh propagated northeastward beneath the Qilina Shan. Southward, the dextral Red River fault accommodated the southeastward extrusion of the Indochina block. During the Miocene, specifically, between 25 and 15 Ma, the Indian slab undergoes a second break-off, while the central part of Tibet is extruded eastward. Northward, the continental subduction beneath the Qilian Shan continues. Discontinuous periods of magmatic activity associated with slab detachments play a fundamental role in the convergence process. These periods lead locally to a softening of the mid-crust by magma heat transfer and to the granulitisation of the lower crust, which becomes more resistant. We propose that due to these alternating periods of softening and hardening of the Tibetan crust, the rheological behaviour of the convergence system evolves in space and time, promoting homogeneous thickening periods alternating with periods of localised crustal or lithospheric deformations.

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47

Liu, Junlai, Mo Ji, Jinlong Ni, Liang Shen, Yuanyuan Zheng, Xiaoyu Chen y John P. Craddock. "Inhomogeneous thinning of a cratonic lithospheric keel by tectonic extension: The Early Cretaceous Jiaodong Peninsula–Liaodong Peninsula extensional provinces, eastern North China craton". GSA Bulletin 133, n.º 1-2 (7 de mayo de 2020): 159–76. http://dx.doi.org/10.1130/b35470.1.

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Abstract The mechanisms of lithospheric thinning and craton destruction have been hotly debated in the last decades. The Early Cretaceous Jiaodong and Liaodong extensional provinces (JEP and LEP, respectively) of the eastern North China craton are typical areas where the cratonic Archean lithosphere has been intensely extended and thinned. Various extensional structures, e.g., metamorphic core complexes (MCCs), low-angle detachment faults, and extensional basins, characterize the Early Cretaceous crustal deformation of the two provinces. However, profound differences exist in structural development and related magmatic activities between the two provinces. Distributed small-scale extensional basins were formed in association with exhumation of the Liaonan and Wanfu MCCs in the LEP, whereas the major Jiaolai Basin was developed coevally with exhumation of the Wulian, Queshan, and Linglong MCCs in the JEP. Sr-Nd isotope compositions of volcanic rocks from the basins of the two provinces are compatible with syntectonic magmatic activities of evolving magma sources in the LEP, but multiple and hybrid magma sources in the JEP. It is shown, from variations in structural styles, plutonic and volcanic activities, and thermal evolution of the two extensional provinces, that two stages (ca. 135–120 Ma and 120–100 Ma) of tectonic extension affected the JEP and LEP in the Early Cretaceous. We demonstrate that regional tectonic extension (parallel extension tectonics, or PET) is responsible for the formation of major extensional structures and the occurrence of the magmatic associations. Progressive wide rifting by coupled crust-mantle detachment faulting of a hot LEP lithosphere was accompanied by evolving magma sources from dominant ancient crust and enriched mantle to juvenile crust. Two stages of narrow rifting of a cold JEP lithosphere led to early crustal detachment faulting transitioning to late crust-mantle faulting, which resulted in intense magmatic activity from hybrid to multiple magma sources. These processes contributed to destruction of the craton, with thinning of its lithospheric keel and local transformation of the nature of the lithospheric mantle. It is expected that such a model is also applicable to interpretation of tectonic extension of contiguous areas of the North China craton and the remobilization of other cratons.

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48

Michibayashi, Katsuyoshi, Makoto Suzuki y Naoaki Komori. "Progressive deformation partitioning and recrystallization of olivine in the lithospheric mantle". Tectonophysics 587 (marzo de 2013): 79–88. http://dx.doi.org/10.1016/j.tecto.2012.07.008.

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49

Knoll, Mickaël, Andréa Tommasi, Roland E. Logé y Javier W. Signorelli. "A multiscale approach to model the anisotropic deformation of lithospheric plates". Geochemistry, Geophysics, Geosystems 10, n.º 8 (agosto de 2009): n/a. http://dx.doi.org/10.1029/2009gc002423.

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50

Sabadini, R. y L. L. A. Vermeersen. "Influence of lithospheric and mantle stratification on global post-seismic deformation". Geophysical Research Letters 24, n.º 16 (15 de agosto de 1997): 2075–78. http://dx.doi.org/10.1029/97gl01979.

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