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1. Do continental lithospheric discontinuities control tectonic plate motion directions

   Kuiper, YD (June 2024, National Association of Geoscience Teachers)

   Plate-tectonic reconstructions use Euler poles about which plates rotate in small circle patterns. These small circle patterns are outlined by oceanic transform faults and contiguous fracture zones. Because oceanic lithosphere older than ~200 Ma is preferentially destroyed by subduction, pre-Mesozoic plate-tectonic reconstructions lack such constraints from oceanic fracture zones. Based on high-resolution bathymetry, geological and geophysical data, some fracture zones are shown to be contiguous with pre-existing discontinuities in adjacent continents. Combined with results from published analog and numerical models, continental rift zones and oceanic spreading ridges that are initially oblique to these discontinuities are demonstrated to evolve into orientations perpendicular to them, while fracture zones and transform faults develop parallel to them. Consequently, oceanic spreading directions, or plate movement directions, are controlled by pre-existing continental lithospheric discontinuities. This hypothesis constitutes a paradigm shift, from the widespread belief that transform fault and fracture zone orientations are controlled by plate motions, to one where they are inherited from pre-existing continental discontinuities, and control plate movement directions. If so, identifying such discontinuities in ancient continental lithosphere may constrain plate motions in deep geologic time. 

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2. Do continental lithospheric discontinuities exert control on tectonic plate motion directions?

   https://doi.org/10.1016/j.gsf.2025.102154  

   Kuiper, Yvette D (November 2025, Geoscience Frontiers)

   Plate motion directions, and the orientations of rift zones and oceanic spreading ridges, and of transform faults and fracture zones that are perpendicular to these ridges, are generally controlled by tectonic forces such as slab pull, mantle convection, and mantle plumes. Here, it is hypothesized that within the confines of these general orientations, the exact orientations of these structures, and therefore plate motion directions, are partially controlled by suitably oriented sets of steep continental lithospheric discontinuities (CLDs), which work in concert with these larger tectonic forces. Previously, the observation has been made that oceanic fracture zones are contiguous with CLDs, such as suture zones and other lithospheric fault zones. Based on high-resolution bathymetry, geological and geophysical data, it is demonstrated here that continents have multiple sets of lineaments parallel to such CLDs, or contiguous with CLDs where they occur farther inland and do not reach the ocean. Published analog experiments suggest that the orientations of transform faults and fracture zones are controlled by these CLDs if the angle between the spreading direction and the CLDs is no more than ∼45°. Spreading ridge segments evolve in an orientation perpendicular to these transform faults and fracture zones, so that the spreading direction becomes parallel to the transform faults and fracture zones. The implication is that the exact plate motion directions are controlled by CLDs, if a set of CLDs is orientated at low angle with the spreading direction. When plate motion directions need to change due to tectonic forces, the new hypothesis predicts that the exact directions may be controlled by a different set of suitably orientated CLDs. During later stages of oceanic spreading, the larger tectonic forces such as slab pull, mantle convection, and mantle plumes become increasingly dominant and plate motion directions may no longer be controlled by the CLDs. While the hypothesis needs further testing, it has potentially far-reaching implications. For example, Euler pole reconstructions are commonly based on small circle patterns formed by fracture zones and transform faults in the oceanic lithosphere. Oceanic crust older than ∼200 Ma is typically destroyed by subduction, and pre-Mesozoic Euler poles can therefore not be reconstructed based on that method. If the hypothesis presented above is correct, the orientations of CLDs and associated lineament sets may be used as proxies for orientations of past transform faults and fracture zones, at least during early oceanic spreading. The locations of past Euler poles may thus be better estimated based on these CLDs and lineaments, and pre-Mesozoic plate tectonic reconstructions may be much improved in deep geologic time. 

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3. Do continental lithospheric discontinuities exert control on tectonic plate motion directions?

   https://doi.org/10.5194/egusphere-egu26-8469  

   Kuiper, Yvette (March 2026, European Geosciences Union)

   Plate motion directions, and the orientations of rift zones and oceanic spreading ridges, and of transform faults and fracture zones that are perpendicular to these ridges, are generally controlled by tectonic forces such as slab pull, mantle convection, and mantle plumes. Here, it is hypothesized that within the confines of these general orientations, the exact orientations of these structures, and therefore plate motion directions, are partially controlled by suitably oriented sets of steep continental lithospheric discontinuities (CLDs), which work in concert with these larger tectonic forces.Previously, the observation has been made that oceanic fracture zones are contiguous with CLDs, such as suture zones and other lithospheric fault zones. Based on high-resolution bathymetry, geological and geophysical data, it is demonstrated here that continents have multiple sets of lineaments parallel to such CLDs, or contiguous with CLDs where they occur farther inland and do not reach the ocean. Published analog experiments suggest that the orientations of transform faults and fracture zones are controlled by these CLDs if the angle between the spreading direction and the CLDs is no more than ~45°. Spreading ridge segments evolve in an orientation perpendicular to these transform faults and fracture zones, so that the spreading direction becomes parallel to the transform faults and fracture zones. The implication is that the exact plate motion directions are controlled by CLDs, if a set of CLDs is orientated at low angle with the spreading direction. When plate motion directions need to change due to tectonic forces, the new hypothesis predicts that the exact directions may be controlled by a different set of suitably orientated CLDs. During later stages of oceanic spreading, the larger tectonic forces such as slab pull, mantle convection, and mantle plumes become increasingly dominant and plate motion directions may no longer be controlled by the CLDs.While the hypothesis needs further testing, it has potentially far-reaching implications. For example, Euler pole reconstructions are commonly based on small circle patterns formed by fracture zones and transform faults in the oceanic lithosphere. Oceanic crust older than ~200 Ma is typically destroyed by subduction, and pre-Mesozoic Euler poles can therefore not be reconstructed based on that method. If the hypothesis presented above is correct, the orientations of CLDs and associated lineament sets may be used as proxies for orientations of past transform faults and fracture zones, at least during early oceanic spreading. The locations of past Euler poles may thus be better estimated based on these CLDs and lineaments, and pre-Mesozoic plate tectonic reconstructions may be much improved in deep geologic time. 

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4. Magmatism controls global oceanic transform fault topography

   https://doi.org/10.1038/s41467-024-46197-9  

   Tian, Xiaochuan; Behn, Mark D; Ito, Garrett; Schierjott, Jana C; Kaus, Boris_J P; Popov, Anton A (December 2024, Nature Communications)

   Abstract Oceanic transform faults play an essential role in plate tectonics. Yet to date, there is no unifying explanation for the global trend in broad-scale transform fault topography, ranging from deep valleys to shallow topographic highs. Using three-dimensional numerical models, we find that spreading-rate dependent magmatism within the transform domain exerts a first-order control on the observed spectrum of transform fault depths. Low-rate magmatism results in deep transform valleys caused by transform-parallel tectonic stretching; intermediate-rate magmatism fully accommodates far-field stretching, but strike-slip motion induces across-transform tension, producing transform strength dependent shallow valleys; high-rate magmatism produces elevated transform zones due to local compression. Our models also address the observation that fracture zones are consistently shallower than their adjacent transform fault zones. These results suggest that plate motion change is not a necessary condition for reproducing oceanic transform topography and that oceanic transform faults are not simple conservative strike-slip plate boundaries. 

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5. Generation of Evolving Plate Boundaries and Toroidal Flow From Visco‐Plastic Damage‐Rheology Mantle Convection and Continents

   https://doi.org/10.1029/2023GC011179  

   Becker, Thorsten W.; Fuchs, Lukas (December 2023, Geochemistry, Geophysics, Geosystems)

   Earth's style of planetary heat transport is characterized by plate tectonics which requires rock strength to be reduced plastically in order to break an otherwise stagnant lithospheric lid, and for rocks to have a memory of past deformation to account for strain localization and the hysteresis implied by geological sutures. Here, we explore ∼10⁷Rayleigh number, visco‐plastic, 3‐D global mantle convection with damage. We show that oceanic lithosphere‐only models generate strong toroidal‐poloidal power ratios and features such as a mix of long‐wavelength tectonic motions and smaller‐scale, back‐arc tectonics driven by downwellings. Undulating divergent plate boundaries can evolve to form overlapping spreading centers and microplates, promoted and perhaps stabilized by the effects of damage with long memory. The inclusion of continental rafts enhances heat flux variability and toroidal flow, including net rotation of the lithosphere, to a level seen in plate reconstructions for the Cenozoic. Both the super‐continental cycle and local rheological descriptions affect heat transport and tectonic deformation across a range of scales, and we showcase both general tectonic dynamics and regionally applied continental breakup scenarios. Our work points toward avenues for renewed analysis of the typical, mean behavior as well as the evolution of fluctuations in geological and model plate boundary evolution scenarios. 

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