Article

Radioactivity and Earth Movements

Authors:
To read the full-text of this research, you can request a copy directly from the author.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the author.

... The central task of the plate tectonics theory at present is to understand mantle convection in general and mantle flow on varying scale in particular. Yet, one of the most popular perceptions in classrooms and textbooks gives an apparently simple picture of coupled flows between the oceanic lithosphere and the subjacent asthenosphere (Fig. 1b,c), following Arthur Holmes' concept of mantle convection in the form of ''convective current" [10], which is useful in telling the reader that the Earth's mantle does convect, but has been used by many to argue that the seafloor spreading (the motion of oceanic lithosphere) is viscously dragged by subjacent mantle ''convective current" (Fig. 1b,c). On the other hand, still others believed the other way round, i.e., the motion of the oceanic lithosphere in response to subducting slab pull induces the subjacent asthenosphere to flow with it. ...
... In summary, the discovery of plate tectonics and its further understanding have proved the long-held view of mantle convection, in which the subducting oceanic lithosphere dictates the first order pattern of mantle convection [5] (Fig. 1a) although details of mantle convection remain speculative. Influenced by the idea of ''convective current" [10], the apparently sensible and popular speculation is the coupled motion of the spreading seafloor lithosphere with the subjacent asthenosphere (Fig. 1b,c), which is erroneous. In terms of basic physics such as mass conservation and the principle of flow continuity, the materials in the LVZ must flow towards the ridge against the spreading seafloor lithosphere to supply the materials needed to form the magmatic ocean crust at the ridge and for continued mantle lithosphere accretion beneath young (t < 70 Ma) lithosphere. ...
... The central task of the plate tectonics theory at present is to understand mantle convection in general and mantle flow on varying scale in particular. Yet, one of the most popular perceptions in classrooms and textbooks gives an apparently simple picture of coupled flows between the oceanic lithosphere and the subjacent asthenosphere (Fig. 1b,c), following Arthur Holmes' concept of mantle convection in the form of ''convective current" [10], which is useful in telling the reader that the Earth's mantle does convect, but has been used by many to argue that the seafloor spreading (the motion of oceanic lithosphere) is viscously dragged by subjacent mantle ''convective current" (Fig. 1b,c). On the other hand, still others believed the other way round, i.e., the motion of the oceanic lithosphere in response to subducting slab pull induces the subjacent asthenosphere to flow with it. ...
... In summary, the discovery of plate tectonics and its further understanding have proved the long-held view of mantle convection, in which the subducting oceanic lithosphere dictates the first order pattern of mantle convection [5] (Fig. 1a) although details of mantle convection remain speculative. Influenced by the idea of ''convective current" [10], the apparently sensible and popular speculation is the coupled motion of the spreading seafloor lithosphere with the subjacent asthenosphere (Fig. 1b,c), which is erroneous. In terms of basic physics such as mass conservation and the principle of flow continuity, the materials in the LVZ must flow towards the ridge against the spreading seafloor lithosphere to supply the materials needed to form the magmatic ocean crust at the ridge and for continued mantle lithosphere accretion beneath young (t < 70 Ma) lithosphere. ...
Article
Full-text available
Evidence of seafloor spreading [1,2] proved the seafloor-spreading hypothesis [3] and led to the discovery of plate tectonics. A further observation-based analysis showed that seafloor-spreading results from downward pulling of the subducting slab [4], which drives plate tectonics and dictates the first order pattern of mantle convection [5] (Fig. 1a). Continental drift is understood as a passive response to trench retreat under gravity due to seafloor subduction [6]. All this, plus the understanding that ocean ridges are passive features [7], has completed the paradigm of the plate tectonics theory. However, a fundamental issue concerning mantle flow subjacent to the spreading oceanic lithosphere remains widely misperceived (Fig. 1b,c), which needs correction so as to better appreciate the efficacies of the plate tectonics theory and to correctly understand the origin and evolution of oceanic lithosphere as well as processes of chemical differentiation of the Earth. Correctly, materials in the seismic low velocity zone (LVZ, top portion of the asthenosphere) beneath ocean basins must flow towards ocean ridges against the spreading oceanic lithosphere above, especially beneath seafloors younger than ~ 70 Ma (Fig. 1d). Given the fundamental importance of this issue, I endeavor in this short communication to convince the reader in simple clarity that oceanic lithosphere-LVZ decoupling is required for the functioning of plate tectonics in terms of mass conservation and continuity principle of fluid mechanics, which is also revealed by geochemical studies [8]. Note that the discussion and illustrations presented here use understood geological and physical principles that are transparent and demonstrative rather than using interpretations based on dynamic/numerical modeling. The latter is useful and important but is often opaque and not unambiguous for understanding the key issue discussed in this paper (e.g., [9]). The central task of the plate tectonics theory at present is to understand mantle convection in general and mantle flow on varying scale in particular. Yet, one of the most popular perceptions in classrooms and textbooks gives an apparently simple picture of coupled flows between the oceanic lithosphere and the subjacent asthenosphere (Fig. 1b,c), following Arthur Holmes' concept of mantle convection in the form of "convective current" [10], which is useful in telling the reader that the Earth's mantle does convect, but has been used by many to argue that the seafloor spreading (the motion of oceanic lithosphere) is viscously dragged by subjacent mantle "convective current" (Fig. 1b,c). On the other hand, still others believed the other way round, i.e., the motion of the oceanic lithosphere in response to subducting slab pull induces the subjacent asthenosphere to flow with it. In either scenario, the lithosphere-asthenosphere motion is closely coupled because of the believed cause-and-effect connection between the two, moving in the same direction away from ocean ridges (Fig. 1b,c). Such coupled motion, as taught in classrooms and illustrated in textbooks, is still popular in current modelling research such as "plug flow in Earth's asthenosphere" [9]. According to the concept of mass conservation and continuity principle of fluid mechanics, it is straightforward that the oceanic lithosphere-LVZ movement is necessarily decoupled, especially beneath young (< 70 Ma) seafloors [11,12] (Fig. 1d). Because ocean ridges are passive features [7], plate separation creates a gravitational void to allow the asthenosphere to rise and melt by Accepted Sci Bull manuscript-20240815 < 2 > decompression to produce the magmatic ocean crust with the residues accreting to the growth of the oceanic lithosphere [13]. That is, continued seafloor spreading leads to continued oceanic lithosphere formation (magmatic crust + mantle lithosphere) and thus continued asthenosphere material supply. In simple words, the mass of the lithosphere accreted per unit time (mL) must be the same as the mass of the asthenosphere supply per unit time (mA; mL= mA). In addition to the contribution of ridge melting residues, the oceanic lithosphere thickens with age by accreting asthenosphere material from below until reaching its full thickness (L) of ~ 90 km at the age (t) of ~ 70 Ma as the result of conductive heat loss to the seafloor, which is expressed by L ∝ t 1/2 [5,7,11]. It follows that the lithosphere accretion is fastest towards the ridge with ~ 50% of the full thickness completed in the first ~17.5 Myrs (i.e., t1/2 = [0.5*70 1/2 ] 2). All this demonstrates in simple clarity that the LVZ, the top portion of the asthenosphere, beneath ocean ridges represents regions of the lowest pressure in the entire mantle that drives the ridgeward flow both locally and globally. The latter is described physically as ridge suction [8] in the context of discussing plume-ridge interactions. The asthenosphere materials needed for the lithosphere accretion at and near ridges can be supplied both vertically from below at great depths and transported laterally by ridge suction (Fig. 1d). However, the LVZ has the lowest viscosity with the top defined by the LAB (lithosphere-asthenosphere boundary) [11] and the base defined by the Lehmann Discontinuity at ~220±30 km (Fig. 1d) that marks the sudden seismic velocity and viscosity increase at depths [14], which informs that the seismic LVZ is also a zone of rheological low viscosity (lvz) [12]. These observations and reasoning, together with the presence of a melt-rich layer close beneath the LAB [11], make the seafloor spreading possible with little resistance [11,12] and make the ridgeward LVZ flow against plate motion physically straightforward while also satisfying the principles of mass conservation and flow continuity. Hence, the lithosphere-LVZ decoupling is required for the functioning of plate tectonics [8]. It follows from the above that the extent of lithosphere-LVZ decoupling must increase with increasing ridge spreading rate because the material needs to form the lithosphere increase with increasing spreading rate. As the full thickness of mature oceanic lithosphere (LFull = ~ 90 km) for seafloors > 70 Ma is independent of spreading rate, the volume of the lithosphere (V) formed per unit time per unit length parallel to the ridge can be calculated using a globally valid form of V = R1/2 * LFull, where R1/2 is the half-spreading rate. As LFull is constant, V ∝ R1/2, and LFull is thus a simple proportionality. By using L = 11t 1/2 [15], it is straightforward to calculate the thickness and volume of the lithosphere formed per unit ridge length as a function of spreading rate for seafloors < 70 Ma. Fig. 2a, as an example, compares V = f(R1/2) formed for the first one million years for scenarios of R1/2 = 10 and 60 mm/yr, respectively. As expected, V[R1/2 = 60 mm/a]/V[R1/2 = 10 mm/a] = 440 km 3 /73.33 km 3 = 6, confirming the linear relationship V ∝ R1/2 that is valid for lithosphere growth globally for active accreting for t < 70 Ma and for the overall net growth calculated from mature lithosphere for t > 70 Ma. Fig. 2b shows such linearity in terms of material supply required for lithosphere formation due to cooling in the first one million years as a function of R1/2. If a ~ 5 km thick magmatic crust is assumed, the material supply would be much greater. In summary, the discovery of plate tectonics and its further understanding have proved the long-held view of mantle convection, in which the subducting oceanic lithosphere dictates the first order pattern of mantle convection [5] (Fig. 1a) although details of mantle convection remain speculative. Influenced by the idea of "convective current" [10], the apparently sensible and popular speculation is the coupled motion of the spreading seafloor lithosphere with the subjacent asthenosphere (Fig. 1b,c), which is erroneous. In terms of basic physics such as mass conservation and the principle of flow continuity, the materials in the LVZ must flow towards the ridge against the spreading seafloor lithosphere to supply the materials needed to form the magmatic ocean crust at the ridge and for continued mantle lithosphere accretion beneath young (t < 70 Ma) lithosphere. The extent of this lithosphere-asthenosphere decoupling increases with increasing seafloor spreading rate, which is illustrated with demonstrations by geochemical systematics of near-ridge hotline seamount lavas as a function of distance to the ridge axis (e.g., The Easter hotline and Foundation hotline seamount chains in the southeast Pacific) [8]. The nature of the low viscosity of the seismic LVZ (i.e., low viscosity zone, lvz) [12] and the presence of a melt-rich layer close beneath the LAB [11,12] makes seafloor spreading possible with little shear friction, which establishes a fundamental condition for the functioning of plate tectonics.
... En 1912, Wegener jette les fondations de la théorie de la dérive des continents, mais sans en expliquer le moteur. Holmes (1930Holmes ( , 1931 propose que la convection est l'une des forces susceptibles d'être à l'origine des mouvements horizontaux de la surface terrestre. ...
... In 1912, Wegener established the foundations of the theory of continental drift, but without explaining its driving force. Holmes (1930Holmes ( , 1931 proposed that convection is one of the forces that may be responsible for horizontal movement of the Earth's surface. ...
Thesis
Full-text available
Crustal Fault Zones (CFZ) are an interesting geological target for high-temperature geothermal resources in naturally frac-tured and deep basement zones. Field and laboratory studies have already shown the ability of these systems to favor fluid flow down to brittle-ductile-transition. However, several key questions about exploration still exist, in particular the role of structural dip, permeability, and the effect of mechanical stress and more broadly the fundamental role of tectonic regimes on fluid flow in naturally fractured basement domains. Considering 2D and 3D numerical modelling, with TH and THM cou-plings, two trends can be identified and integrated for the exploration of these targets (i) vertical faults concentrate the high-est temperature anomalies at the shallowest depths (ii) strike-slip systems favor the largest temperature anomalies. Geologi-cal and geophysical data suggest that, the Pontgibaud fault zone (French Massif Central) is a CFZ that host an active hydro-thermal system at a depth of a few kilometers. We conducted an integrated study to assess its high temperature geothermal potential. Field measurements are used to control the 3D geometry of the geological structures. 2D (thin-section) and 3D (X-ray microtomography) observations point to a well-defined spatial propagation of fractures and voids, exhibiting the same fracture architecture on different scales (2.5 μm to 2 mm). Moreover, measurements of porosity and permeability confirm that the highly fractured and altered samples are characterized by high permeability values, with one sample characterized by a permeability as high as 10-12 m2. Finally, a large-scale 3D numerical model of the Pontgibaud CFZ, based on THM cou-pling and the comparison with field data (temperature, heat flux, and electrical resistivity), allowed to explore the spatial ex-tent of the 150°C isotherm, which rises up to a depth of 2.3 km. Though based on simplified hypotheses, our model repro-duces field data. A multi-disciplinary integrative approach based on coupled 3D modeling proved to be an efficient way to assess the geothermal potential of CFZ and predict temperature distributions. It can be used as a predictive tool to develop high-temperature geothermal operations within basement rocks hosting large-scale fault systems.
... En 1912, Wegener jette les fondations de la théorie de la dérive des continents, mais sans en expliquer le moteur. Holmes (1930Holmes ( , 1931 propose que la convection est l'une des forces susceptibles d'être à l'origine des mouvements horizontaux de la surface terrestre. ...
... In 1912, Wegener established the foundations of the theory of continental drift, but without explaining its driving force. Holmes (1930Holmes ( , 1931 proposed that convection is one of the forces that may be responsible for horizontal movement of the Earth's surface. ...
Thesis
Full-text available
Crustal Fault Zones (CFZ) are an interesting geological target for high-temperature geothermal resources in naturally frac-tured and deep basement zones. Field and laboratory studies have already shown the ability of these systems to favor fluid flow down to brittle-ductile-transition. However, several key questions about exploration still exist, in particular the role of structural dip, permeability, and the effect of mechanical stress and more broadly the fundamental role of tectonic regimes on fluid flow in naturally fractured basement domains. Considering 2D and 3D numerical modelling, with TH and THM cou-plings, two trends can be identified and integrated for the exploration of these targets (i) vertical faults concentrate the high-est temperature anomalies at the shallowest depths (ii) strike-slip systems favor the largest temperature anomalies. Geologi-cal and geophysical data suggest that, the Pontgibaud fault zone (French Massif Central) is a CFZ that host an active hydro-thermal system at a depth of a few kilometers. We conducted an integrated study to assess its high temperature geothermal potential. Field measurements are used to control the 3D geometry of the geological structures. 2D (thin-section) and 3D (X-ray microtomography) observations point to a well-defined spatial propagation of fractures and voids, exhibiting the same fracture architecture on different scales (2.5 μm to 2 mm). Moreover, measurements of porosity and permeability confirm that the highly fractured and altered samples are characterized by high permeability values, with one sample characterized by a permeability as high as 10-12 m2. Finally, a large-scale 3D numerical model of the Pontgibaud CFZ, based on THM cou-pling and the comparison with field data (temperature, heat flux, and electrical resistivity), allowed to explore the spatial ex-tent of the 150°C isotherm, which rises up to a depth of 2.3 km. Though based on simplified hypotheses, our model repro-duces field data. A multi-disciplinary integrative approach based on coupled 3D modeling proved to be an efficient way to assess the geothermal potential of CFZ and predict temperature distributions. It can be used as a predictive tool to develop high-temperature geothermal operations within basement rocks hosting large-scale fault systems.
... Largely because of the reports by Anglo-Persian, Oil Search Limited was incorporated in Port Moresby on 17 January 1929 having previously carried out exploration in Queensland. Shortly after its incorporation, the company acquired Oriomo Oil Company, which had drilled 16 shallow wells in Papua between 1927and 1928(Rickwood 1990. The company showed tremendous resilience, faith and patience -it received its first production revenues in 1992, 63 years after its incorporation (https://www.oilsearch.com/whowe-are/history). ...
... 30, 31) and said of him: "developing the great new highway of thought blazed by Wegener, has prepared a masterly synthesis of the Gondwana continents for the Palaeozoic and Mesozoic eras" (Carey 1938b, p. 81). • He quoted Professor Arthur Holmes (Holmes 1928) making 'an important contribution from the theoretical side and discussed sub-crustal convection movements arising from differential radio-active heating as a mechanism of orogenesis' and that Holmes' theory of sub-crustal convection movement satisfactorily accounts for the tectonic facts of Melanesia (Carey 1938b, p. 88). • He also quoted Andrews (1938): 'Wegner by this imaginative excursion, was led to infer the impermanence of position of the major structures of the Earth, such as the continents and oceans' (Carey 1938b, p. 93). ...
... We often say that Earth's internal heat powers most geological processes, but precisely speaking the powering mechanism is Earth's heat loss to surface. This can be understood because relative to Earth's deep interiors, the shallow mantle loses heat readily, making the shallow mantle material cool, dense, and tend to sink due to gravity, while displacing the warm deep mantle material to rise due to thermal buoyancy, forming the classic mantle convection current circuit proposed by Arthur Holmes (Holmes, 1931). Although this convection current picture is too simplistic and is likely incorrect as we understand today, it nevertheless correctly depicts the concept of thermal convection as the result of Earth's cooling. ...
... Cartoons on the right are my interpretations to show that ridge push (F RP ) and basal drag (F BD ), which, considered two other important forces, are in fact unimportant or less important if any for plate motion. potential driving force (Holmes, 1931), "magma engine" (Sun, 2019), "six geospheric poles" (Li et al., 2019a,b) and perhaps many others, but the physical and geological validity and rigor of these ideas need comprehensive testing. At the time of this writing, I accept the theory of plate tectonics as we understand today including the driving mechanisms because this theory has undergone hot debate and scrutiny of over a century, including the ∼60-year "continental drift" debate and over 50-year improvements since its acceptance (e.g., Wilson, 1963aWilson, ,b, 1965Wilson, , 1966McKenzie & Parker, 1967;Sykes, 1967;Morgan, 1968;Isacks & Oliver, 1968;Le Pichon, 1968). ...
Article
Full-text available
Earth’s continents can come together to form supercontinents and the supercontinents can break apart into fragments of varying size scattering around the globe through a hypothetical process called continental drift. The continental drift hypothesis had survived after ∼ 60 years debate and evolved into the powerful theory of plate tectonics with unquestionable and irrefutable lines of evidence. This narrative statement is familiar and acceptable to everyone in the scientific community, but scientists differ when talking about the cause of continental breakup. Some advocate mantle plumes, especially superplumes, as the cause (“bottom up”), whereas others emphasize plate tectonics to be the cause (“top down”) and still some believe both are needed. In this short paper, I do not wish to enter the debate, but offer a readily understandable geological analysis on the likely driving mechanisms of plate tectonics and mantle plumes, which leads to the conclusion that continental breakup is a straightforward consequence of plate tectonics without requiring mantle plumes. Mantle plumes, if needed, may be of help at the early rifting stage, but cannot lead to complete breakup, let alone to drive long distance dispersal of broken continents. Superplumes invoked by many do not exist. The debate may continue, but I encourage enthusiastic debaters to consider these straightforward concepts and principles of geology and physics given in this analysis.
... We often say that Earth's internal heat powers most geological processes, but precisely speaking the powering mechanism is Earth's heat loss to surface. This can be understood because relative to Earth's deep interiors, the shallow mantle loses heat readily, making the shallow mantle material cool, dense, and tend to sink due to gravity, while displacing the warm deep mantle material to rise due to thermal buoyancy, forming the classic mantle convection current circuit proposed by Arthur Holmes (Holmes, 1931). Although this convection current picture is too simplistic and is likely incorrect as we understand today, it nevertheless correctly depicts the concept of thermal convection as the result of Earth's cooling. ...
... Cartoons on the right are my interpretations to show that ridge push (F RP ) and basal drag (F BD ), which, considered two other important forces, are in fact unimportant or less important if any for plate motion. potential driving force (Holmes, 1931), "magma engine" (Sun, 2019), "six geospheric poles" (Li et al., 2019a,b) and perhaps many others, but the physical and geological validity and rigor of these ideas need comprehensive testing. At the time of this writing, I accept the theory of plate tectonics as we understand today including the driving mechanisms because this theory has undergone hot debate and scrutiny of over a century, including the ∼60-year "continental drift" debate and over 50-year improvements since its acceptance (e.g., Wilson, 1963aWilson, ,b, 1965Wilson, , 1966McKenzie & Parker, 1967;Sykes, 1967;Morgan, 1968;Isacks & Oliver, 1968;Le Pichon, 1968). ...
Article
Earth’s continents can come together to form supercontinents and the supercontinents can break apart into fragments of varying size scattering around the globe through a hypothetical process called continental drift. The continental drift hypothesis had survived after ∼ 60 years debate and evolved into the powerful theory of plate tectonics with unquestionable and irrefutable lines of evidence. This narrative statement is familiar and acceptable to everyone in the scientific community, but scientists differ when talking about the cause of continental breakup. Some advocate mantle plumes, especially superplumes, as the cause (“bottom up”), whereas others emphasize plate tectonics to be the cause (“top down”) and still some believe both are needed. In this short paper, I do not wish to enter the debate, but offer a readily understandable geological analysis on the likely driving mechanisms of plate tectonics and mantle plumes, which leads to the conclusion that continental breakup is a straightforward consequence of plate tectonics without requiring mantle plumes. Mantle plumes, if needed, may be of help at the early rifting stage, but cannot lead to complete breakup, let alone to drive long distance dispersal of broken continents. Superplumes invoked by many do not exist. The debate may continue, but I encourage enthusiastic debaters to consider these straightforward concepts and principles of geology and physics given in this analysis.
... For about 4 decades, following Wegener's first presentation of his hypothesis, proselytes who publicly defended drift were very few -the most significant geologists supporting drift in a general way were Daly (1923 and1926), Holmes (1928Holmes ( , 1929 and du Toit (1927 and. Both Daly and Holmes had turned to drift due to their problems with the classical concepts -such as thermal contraction, fixed continents and permanent ocean basins, and the isostasy models. ...
... To the knowledge of the present author, the paradoxical palaeoclimate problem posed by Antarctica seems not to have been discussed at all by the opponents of drift. For example, Arthur Holmes (1928Holmes ( , 1929Holmes ( and 1944, one of Wegener's few faithful supporters, either ignored or explained away Northern Hemisphere Permo-Carboniferous traces of glacial activity and though he admitted that "the position to be allotted to Antarctica is necessarily uncertain", he did not mention the growing fossil evidence from this continent contradicting the ancient polar location which was a first order assumption in the drift hypothesis. As a fan of drift, Holmes reiterated contemporary ideas on convective solid state flow in the mantle (Bull, 1921 and) -as an adequate causal mechanism of drift and its supposedly related driver of mountain formation. ...
Article
Full-text available
The question of distribution of medium density depending on changes of deformations is studied and shown that this dependence for various geological media is instable. Distinguishing the various forms of instability is shown, that depending on geometric forms of bodies and structures of medium these processes contribute to emergence of structures, which are favorable for formation of deconsolidation zones. Comparing the received theoretical results with results of known experimental researches is shown that the processes of loss of stability of elastic equilibrium state on geometric shape change and on “internal” instability precedes to the processes of phase transitions of various mineral systems. These questions are studied using non classical linearized approach within framework of theory of small and large initial deformations involving various elastic potentials. Keywords: dynamics of the Earth, deformation, consolidation, deconsolidation, stability, phase transition
... For about 4 decades, following Wegener's first presentation of his hypothesis, proselytes who publicly defended drift were very few -the most significant geologists supporting drift in a general way were Daly (1923 and1926), Holmes (1928Holmes ( , 1929 and du Toit (1927 and. Both Daly and Holmes had turned to drift due to their problems with the classical concepts -such as thermal contraction, fixed continents and permanent ocean basins, and the isostasy models. ...
... To the knowledge of the present author, the paradoxical palaeoclimate problem posed by Antarctica seems not to have been discussed at all by the opponents of drift. For example, Arthur Holmes (1928Holmes ( , 1929Holmes ( and 1944, one of Wegener's few faithful supporters, either ignored or explained away Northern Hemisphere Permo-Carboniferous traces of glacial activity and though he admitted that "the position to be allotted to Antarctica is necessarily uncertain", he did not mention the growing fossil evidence from this continent contradicting the ancient polar location which was a first order assumption in the drift hypothesis. As a fan of drift, Holmes reiterated contemporary ideas on convective solid state flow in the mantle (Bull, 1921 and) -as an adequate causal mechanism of drift and its supposedly related driver of mountain formation. ...
Article
Full-text available
The question of distribution of medium density depending on changes of deformations is studied and shown that this dependence for various geological media is instable. Distinguishing the various forms of instability is shown, that depending on geometric forms of bodies and structures of medium these processes contribute to emergence of structures, which are favorable for formation of deconsolidation zones. Comparing the received theoretical results with results of known experimental researches is shown that the processes of loss of stability of elastic equilibrium state on geometric shape change and on “internal” instability precedes to the processes of phase transitions of various mineral systems. These questions are studied using non classical linearized approach within framework of theory of small and large initial deformations involving various elastic potentials
... Esto trajo, por consiguiente, la búsqueda de un proceso que conceptualizara la movilidad de los continentes. En 1929, Holmes propuso el llamado proceso de convección en el manto, con el que intentó explicar el movimiento de los continentes en la teoría de deriva continental (Holmes, 1931). No obstante, la conceptualización de este proceso tuvo que esperar hasta el año de 1962 con el aporte del geólogo estadounidense Harry Hess . ...
Article
Full-text available
La existencia de diferentes capas en el interior de la Tierra fue algo desconocido todavía hacia finales del siglo XIX. Su conformación y desarrollo actual conllevó todo un proceso evolutivo de millones de años por el que tuvo que pasar el planeta entero, el cual sigue siendo objeto de estudio. En este escrito, se describe y explica cómo, a partir de la Sismología como área de estudio, se pudo reconocer la existencia de diferentes capas en el interior de la Tierra. Así mismo, se explica de manera concisa cómo a partir de este reconocimiento, se propusieron las bases para el establecimiento de los procesos y mecanismos dinámicos que hasta el día de hoy han permitido sustentar la formación y evolución de las capas internas y del planeta mismo.
... The long-awaited explanation to these queries has been provided by the concept of mantle convection and plate tectonics theory [1,2]. Arthur Holmes [3,4] was the first to propose the idea of the convection in the mantle. Mantle convection modifies the planetary surfaces and propels geological activity and for a long period of time, it has been the driving mechanism of various physical phenomena [5]. ...
Article
Full-text available
Mantle convection, a fundamental mechanism controlling the dynamics of the Earth's surface and interior, shows different behaviors caused by different factors such as viscosity variation, viscous dissipation, internal heating, and so on. In this paper, the effects of temperature-dependent viscosity, temperature and pressure-dependent viscosity and viscous dissipation on mantle convection are investigated in elongated and narrow cells. The Rayleigh-Bénard convection model is solved numerically with the full form of the Arrhenius viscosity function at a high Rayleigh number for viscosity contrasts up to 10 30. The root mean square velocity and Nusselt number are computed and tabulated. The thermal characteristics and flow dynamics inside the convection cell are presented by temperature profiles and stream function contours. These simulated results indicate that increasing viscosity contrasts with the incorporation of viscous dissipation weakens the convection vigour and heat transfer in the mantle. The selected narrow cell remains stable for a very high viscosity contrast at different viscous pressure number µ, whereas the selected elongated cell with temperature-dependent viscosity and strong viscous dissipation becomes unstable and single-cell pattern breaks down at high viscosity variation.
... The long-awaited explanation to these queries has been provided by the concept of mantle convection and plate tectonics theory [1,2]. Arthur Holmes [3,4] was the first to propose the idea of the convection in the mantle. Mantle convection modifies the planetary surfaces and propels geological activity and for a long period of time, it has been the driving mechanism of various physical phenomena [5]. ...
Article
Mantle convection, a fundamental mechanism controlling the dynamics of the Earth’s surface and interior, shows different behaviors caused by different factors such as viscosity variation, viscous dissipation, internal heating, and so on. In this paper, the effects of temperature-dependent viscosity, temperature and pressure-dependent viscosity and viscous dissipation on mantle convection are investigated in elongated and narrow cells. The Rayleigh-B´enard convection model is solved numerically with the full form of the Arrhenius viscosity function at a high Rayleigh number for viscosity contrasts up to 1030. The root mean square velocity and Nusselt number are computed and tabulated. The thermal characteristics and flow dynamics inside the convection cell are presented by temperature profiles and stream function contours. These simulated results indicate that increasing viscosity contrasts with the incorporation of viscous dissipation weakens the convection vigour and heat transfer in the mantle. The selected narrow cell remains stable for a very high viscosity contrast at different viscous pressure number μ, whereas the selected elongated cell with temperature-dependent viscosity and strong viscous dissipation becomes unstable and single-cell pattern breaks down at high viscosity variation. J. Bangladesh Math. Soc. 44.2 (2024) 077–096
... He was, however, unable to provide robust evidence for the processes that had led to this drift of continents and the theory remained controversial for years. Between 1920 and 1930, the geologist Arthur Holmes published work proposing that plate junctions under the ocean and convective cells and radioactive heat in the Earth's mantle might drive the process of continental drift (Holmes, 1928(Holmes, , 1929. The discovery of the continuous nature of the mid-ocean ridges by Ewing's team in the 1950s and 1960s (e.g. ...
Article
We review discoveries in deep-sea biodiversity since the establishment of the International Hydrographic Organisation in 1921. Over the last century it has been demonstrated that the deep sea harbours a great variety of habitats which host a large diversity of species rivalling that of other marine and terrestrial ecosystems. This was possible through the invention of quantitative sampling methods and deep-submergence technologies as well as advances in fields such as acoustics and marine navigation. Increasing human activities impacting the deep ocean now demand knowledge of the distribution of life in the deep sea is greatly improved through further exploration.
... Ocean basins and mountains were explained by vertical movements, such as those caused by local isostasy or an expanding or shrinking Earth (Dana, 1863;Mantovani, 1889). The formulation of the mantle convection theory, with large-scale flows driven by energy from radiogenic decay and residual heat from Earth's formation, provided an explanation for horizontal plate motions (Holmes, 1931;Dietz, 1961;Hess, 1962). Proof came in the 1950s and 1960s from continental paleomagnetic poles and marine magnetic anomalies (Heezen et al., 1959;Vine and Matthews, 1963;Runcorn, 1965). ...
... Tao and O'Connell, 1992). The lateral compression in these pre-plate tectonics models was proposed to have been caused by basal drag due to convection in the substratum, as proposed earlier by Holmes (1931), that turned vertically downward below the down-buckled crust (Vening-Meinesz, 1934;Escher;1933;Umbgrove, 1934). ...
... The two supercontinents of Gondwanaland and Laurasia were separated by a wide belt of a shallow sea called the Tethys sea and surrounded by a vast ocean called Panthalasa that was the proto-Mediterranean Sea and proto-Pacific ocean respectively ( Arias, 2008 ). Afterward, the discovery of convection current in the mantle by Holmes (1928) due to the heat of radioactive decay may cause for drifting of the continents across the Earth's surface. In the 1940s and 1950s, the development of paleomagnetism and radiometric dating indicates that the position and orientation of magnetic poles in many continental rocks differ from the present time period which also proved that continents are not always in the same position ( Collinson and Runcorn, 1960 ). ...
Article
Full-text available
Global tectonic activities are playing an important role in the occurrences of devastating earthquakes and related long-term changes in the earth's system surface. However, the plate tectonics processes and their interaction with the earth's crust are very much complex, and it is a subject of unending debate. Therefore, tectonism-induced landslide, tsunami, liquefaction, and fire are significant earthquake-related hazards, which have a larger potential and overwhelming impact on life and infrastructural properties throughout the world. In this study, we have emphasized the identification of earthquake hotspot and coldspot zones considering historical earthquake data across the plate boundary of the world. Here, a total of 7773 historical earthquake points were collected as input parameters with three-moment magnitude (Mw) classes (<4.5, 4.5-6.0, and >6.0). Two statistical methods namely hotspot analysis (Getis-Ord GI*) and optimized hotspot analysis were used in the detection of global earthquake hotspot and coldspot zones using the geographic information system (GIS) platform. Hotspot and coldspot zone are identified under 99%, 95%, and 90% confidence levels. Alongside, here we have also discussed the paradigm, evidence of tectonic, and historical earthquakes, and how and why they are formed with the help of the existing theoretical constraints. The result indicates that the Pacific ring of fire, Peru-Chile Trench, and the mid-Atlantic oceanic ridge is fall in the hotspot zones of 99%, 95%, and 90% confidence levels.
... The concept of mantle convection goes back a century to the initial proposal that convection currents in Earth's mantle actively drive continental drift and that crustal deformation is a passive response ( Holmes, 1931 ). In general, the active mantle convection is symmetric and often seen in Early Earth, but the passive mantle convection is asymmetric and usually seen under plate tectonic regime. ...
Article
Full-text available
Magmatism has occurred throughout Earth's history. From the early Earth to the modern plate-tectonic Earth, the amount of magmatism has varied, but it has always occurred on multiple scales, in various tectonic environments and at various depths in the crust and mantle. Magma compositions also vary. In this paper, we argue that the mechanism of magma emplacement has generally been passive at all stages of Earth evolution. We conclude that most magmatism related to subduction, rifting, mid-oceanic spreading, flood basalts and large igneous provinces and related to mantle upwellings, magma underplating, slab windows, orogenic collisions as well as Archean TTG formation are predominantly passive from the lithosphere-scale to the crystal-scale. Our results weigh against the view that magmatism drives plate motions. Most of the magmatism on other Earth-like planets is also passive regardless of the tectonic environments.
... and global view of the Earth evolution. Then, Arthur Holmes's mantle convection theory 159 (Holmes, 1931), the first idea of seafloor spreading (Hess, 1962), the description of symmetric 160 seafloor spreading anomalies (Vine and Matthews, 1963) and the understanding of the 161 significance of transform faults (Tuzo Wilson, 1965) enabled to propose a uniform, coherent 162 ...
Article
Full-text available
The aim of this paper is to provide a conceptual framework that integrates the role of inheritance in the study of rifts, rifted margins and collisional orogens based on the work done in the OROGEN project, which focuses on the Biscay-Pyrenean system. The Biscay-Pyrenean rift system resulted from a complex multistage rift evolution that developed over a complex lithosphere pre-structured by the Variscan orogenic cycle. There is a general agreement that the Pyrenean-Cantabrian orogen resulted from the reactivation of an increasingly mature rift system along-strike, ranging from a mature rifted margin in the west to an immature and segmented hyperextended rift in the east. However, different models have been proposed to explain the preceding syn-rift evolution and its influence on the subsequent reactivation. Results from the OROGEN project show a sequential reactivation of rift inherited decoupling horizons and identify the specific role of exhumed mantle, hyperextended and necking domains during reactivation. They also highlight the contrasting fate of segment centres vs. segment boundaries during convergence, explaining the non-cylindricity of internal parts of collisional orogens. Results from the OROGEN project also suggest that the role of inheritance is more important during the initial stages of subduction and collision, which may explain the complexity of internal parts of orogenic systems. In contrast, once tectonic systems get more mature, orogenic evolution becomes mostly controlled by first-order physical processes as described in the Coulomb Wedge theory for instance. This may account for the simpler and more continuous architecture of external parts of collisional orogens. It may also explain why most numerical models can reproduce mature orogenic and rift architectures with better accuracy compared to the initial stages of such systems. Thus, while inheritance may not explain steady-state processes, it is a prerequisite for comprehending the initial stages of tectonic systems. The new concepts developed from the OROGEN research are now ready to be tested at other orogenic systems that result from the reactivation of rifted margins, such as the Alps, the Colombian cordilleras and the Caribbean, Taiwan, Oman, Zagros or Timor.
... Для склонов хребтов имеется высочайшая скорость эрозии, а для плато и внутригорных впадин -минимальная. Данные фишин-трек анализа показывают, что породы, находящиеся сейчас на склонах хребтов, еще 5-10 млн лет назад были на глубине около 3-4 км (например, для Тянь-Шаня [60] и Кавказа [59]). Это в 5-7 раз больше, чем разница их современного положения на склоне и высоты пика хребтов, которые для Алтая и Тянь-Шаня часто представлены пенепленом [34,60]. ...
Article
Full-text available
Результаты тектонофизической инверсии глобального поля тектонических напряжений рассматриваются с позиции объяснения активных сил, обуславливающих движение литосферных плит. Выполнен анализ закономерностей напряженного состояния главных структурных элементов литосферы Земли – океанского спрединга, трансформов, активных континентальных окраин, внутриконтинентальных орогенов. Показано, что напряжения в большей части океанской литосферы, включая зоны субдукции, отвечают активным тяговым силам от погруженной и утяжеленной части литосферы. Установлен низкий уровень девиаторных напряжений в зонах субдукции и наличие динамо-пары с резко различающимся режимом напряженного состояния. В коре континентального склона наблюдается горизонтальное сжатие, в океанской литосфере – горизонтальное растяжение, поэтому границы литосферных плит не следует рассматривать в виде источника напряжений повышенного горизонтального сжатия в коре континентов. Формирование режима горизонтального сжатия в коре внутриконтинентальных орогенов, как и в коре орогенов активных континентальных окраин связано с остаточными напряжениями пород, подвергшихся эксгумации из глубин коры. Предлагается обобщающая схема формирования глобального поля коровых напряжений Земли, отвечающая современным данным о движениях литосферных плит и глубинному строению верхней мантии.
... The slopes of ridges have the highest erosion rate, whereas plateaus and intramontane depressions have the minimum. Fission track analysis data show that rocks now on the slopes of ridges were at a depth of about 3-4 km 5-10 Ma (e.g., for the Tien Shan [60] and Caucasus [59]). This is 5-7 times more than the difference between their present position on the slope and the height of ridge peaks, which are often represented by peneplains for Altai and the Tien Shan [34,60]. ...
Article
Full-text available
The results of tectonophysical inversion of the global tectonic stress field are considered from the position of explaining the active forces that cause the lithospheric plate movements. The analysis of regularities of the stress state of the main structural elements of Earth's lithosphere-ocean spreading, transformations , active continental margins, and intracontinental orogeny-is performed. It is shown that the stresses in most of the ocean lithosphere, including subduction zones, correspond to active traction forces from the submerged and weighted part of the lithosphere. A low level of deviatoric stresses in subduction zones and the presence of dynamo pair with sharply different mode of stress state were found. Horizontal compression is observed in the crust of the continental slope, and horizontal tension is observed in the ocean lithosphere, so the boundaries of lithospheric plates should not be considered as a source of increased horizontal compressive stress in the crust of continents. The formation of a horizontal compression regime in the crust of intracon-tinental orogens, as well as in the crust of active continental margins orogens, is associated with residual stresses of rocks that have been exhumed from the depths of the crust. A generalizing scheme for the formation of the global crustal stress field of the Earth is proposed, which corresponds to modern data on the movements of lithospheric plates and the deep structure of the upper mantle.
... Holmes [27] 就提出地幔对流是驱动板块运动的主要动 力. Hess [10] 在提出扩张洋脊的概念时也强调了地幔对 流的作用. ...
... 83 84 2. Heat loss drives Earth processes 85 86 We often say that Earth's internal heat powers most geological processes, but precisely 87 speaking the powering mechanism is Earth's heat loss to surface. This can be understood 88 because relative to Earth's deep interiors, the shallow mantle loses heat readily, making the 89 shallow mantle material cool, dense, and tend to sink due to gravity, while displacing the warm 90 deep mantle material to rise also due to gravity, forming the classic mantle convection current 91 circuit proposed by Arthur Holmes (Holmes, 1931). Although this convection current picture 92 Page 4 of 43 is too simplistic and is likely incorrect as we understand today, it nevertheless correctly depicts 93 the concept of thermal convection as the result of Earth's cooling. ...
Preprint
Full-text available
My logical, objective and simple analysis leads to the conclusion that continental breakup is a straightforward consequence of plate tectonics without requiring mantle plumes. Mantle plumes, if needed, may be of help at the early rifting stage, but cannot lead to complete breakup, let alone to drive long distance dispersal of broken continents. The latter can only be driven directly or indirectly by seafloor pulling into the mantle through trenches and subduction zones with no exception.
... Whether this extensive magmatism reflects an increased mantle heatflow related to effects of the Nuna supercontinent on the structure and planform of upwelling motions in a thermally well-stirred mantle (Hoffman, 1989) or requires enhanced subcontinental mantle temperatures and melting more characteristic of mantle thermal isolation is unclear on petrologic grounds (e.g., Longhi, 2005;Morse, 1982;Taylor et al., 1984)Enhanced mantle temperatures are, for example, not required by statistical reconstructions of the MgO contents of mafic melts and of the extent of mantle melting during this period (Keller & Schoene, 2012). However, a marked feature of simulations with extensive (or assumed extensive) mantle thermal mixing is that mantle upwelling flows can become reorganized and focused beneath a growing or well-established supercontinent (e.g., Coltice et al., 2009;Grigné et al., 2007;Holmes, 1931;Lenardic et al., 2011;Li & Zhong, 2009;O'Neill et al., 2009;Pekeris, 1935;Rolf et al., 2012). Thus, an absence of significant ice sheets and the extensive occurrence of anorthosite massifs and related granitic and granodioritic plutonic bodies are not unexpected. ...
Article
Full-text available
Supercontinent assembly and breakup can influence the rate and global extent to which insulated and relatively warm subcontinental mantle is mixed globally, potentially introducing lateral oceanic‐continental mantle temperature variations that regulate volcanic and weathering controls on Earth's long‐term carbon cycle for a few hundred million years. We propose that the relatively warm and unchanging climate of the Nuna supercontinental epoch (1.8–1.3 Ga) is characteristic of thorough mantle thermal mixing. By contrast, the extreme cooling‐warming climate variability of the Neoproterozoic Rodinia episode (1–0.63 Ga) and the more modest but similar climate change during the Mesozoic Pangea cycle (0.3–0.05 Ga) are characteristic features of the effects of subcontinental mantle thermal isolation with differing longevity. A tectonically modulated carbon cycle model coupled to a one‐dimensional energy balance climate model predicts the qualitative form of Mesozoic climate evolution expressed in tropical sea‐surface temperature and ice sheet proxy data. Applied to the Neoproterozoic, this supercontinental control can drive Earth into, as well as out of, a continuous or intermittently panglacial climate, consistent with aspects of proxy data for the Cryogenian‐Ediacaran period. The timing and magnitude of this cooling‐warming climate variability depends, however, on the detailed character of mantle thermal mixing, which is incompletely constrained. We show also that the predominant modes of chemical weathering and a tectonically paced abiotic methane production at mid‐ocean ridges can modulate the intensity of this climate change. For the Nuna epoch, the model predicts a relatively warm and ice‐free climate related to mantle dynamics potentially consistent with the intense anorogenic magmatism of this period.
... "Bottom up" means that tectonic plates represent the outer boundary layer of mantle convection cells, and their movement is controlled by the motion of the underlying mantle system (left part of Figure 2). The idea was proposed prior to the establishment of the plate tectonics theory, e.g, in the 1930s and 1960s, in Arthur Holmes and Harry Hammond Hess's books (Holmes, 1931;Hess, 1962). During the time the theory of plate tectonics was established, Tuzo Wilson and Jason Morgan further developed this idea. ...
Article
Full-text available
Plate tectonics describes the horizontal motions of lithospheric plates, the Earth’s outer shell, and interactions among them across the Earth’s surface. Since the establishment of the theory of plate tectonics about half a century ago, considerable debates have remained regarding the driving forces for plate motion. The early “Bottom up” view, i.e., the converting mantle-driven mechanism, states that mantle plumes originating from the core-mantle boundary act at the base of plates, accelerating continental breakup and driving plate motion. Toward the present, however, the “Top down” idea is more widely accepted, according to which the negative buoyancy of oceanic plates is the dominant driving force for plate motion, and the subducting slabs control surface tectonics and mantle convection. In this regard, plate tectonics is also known as subduction tectonics. “Top down”tectonics has received wide supports from numerous geological and geophysical observations. On the other hand, recent studies indicate that the acceleration/deceleration of individual plates over the million-year timescale may reflect the effects of mantle plumes. It is also suggested that surface uplift and subsidence within stable cratonic areas are correlated with plume-related magmatic activities over the hundred-million-year timescale. On the global scale, the cyclical supercontinent assembly and breakup seem to be coupled with superplume activities during the past two billion years. These correlations over various spatial and temporal scales indicate the close relationship and intensive interactions between plate tectonics and plume tectonics throughout the history of the Earth and the considerable influence of plumes on plate motion. Indeed, we can acquire a comprehensive understanding of the driving forces for plate motion and operation mechanism of the Earth’s dynamic system only through joint analyses and integrated studies on plate tectonics and plume tectonics.
... They provide an explanation for the subduction of a light and buoyant continental lithosphere into the mantle in a collision context, emphasizing the role of far field forces instead of subduction related forces, typically slab pull. Most importantly, this process obviously rules out slab pull as the omnipotent driver of plate tectonics and calls back to the more ancient conveyor belt view advocated by Holmes (1929). ...
... Plate tectonic theory began to generate more interest throughout the 1960s and previous work in support of the hypothesis was brought to the forefront of earth science research (e.g. Agrand 1924;Wegener 1924;Holmes 1931;Du Toit 1937). In 1966, based on evidence in the fossil record and the dating of vestiges of ancient volcanoes, Wilson proposed a cycle describing the opening and closing of oceanic basins, and therefore a method of amalgamating continental material that would subsequently be dispersed. ...
Article
Full-text available
This review discusses the thermal evolution of the mantle following large-scale tectonic activities such as continental collision and continental rifting. About 300 myr ago, continental material amalgamated through the large-scale subduction of oceanic seafloor, marking the termination of one or more oceanic basins (e.g. Wilson cycles) and the formation of the supercontinent Pangaea. The present day location of the continents is due to the rifting apart of Pangaea, with the dispersal of the supercontinent being characterized by increased volcanic activity linked to the generation of deep mantle plumes. The discussion presented here investigates theories regarding the thermal evolution of the mantle (e.g. mantle temperatures and sub-continental plumes) following the formation of a supercontinent. Rifting, orogenesis and mass eruptions from large igneous provinces change the landscape of the lithosphere, whereas processes related to the initiation and termination of oceanic subduction have a profound impact on deep mantle reservoirs and thermal upwelling through the modification of mantle flow. Upwelling and downwelling in mantle convection are dynamically linked and can influence processes from the crust to the core, placing the Wilson cycle and the evolution of oceans at the forefront of our dynamic Earth.
... Arthur Holmes was probably the most influential of these. In 1929 (Holmes, 1929), he proposed convection currents with uplift and consequent extension under the oceanic ridges and downwelling along ocean deeps. His diagram of this precursory conveyor belt system is now quite famous, but did not have much impact on the actual research then. ...
Article
Full-text available
I suggest that the Earth Sciences in the mid‐1950s entered a state of supercooling where the smallest input could lead to the simultaneous crystallization of new ideas. In 1959, I joined the Lamont Geological Observatory, one of the hotbeds where the Plate Tectonic revolution germinated. This paper is not an exhaustive history from an unbiased outside observer. It is a report of one of the participants who interacted with quite a few of the main actors of this revolution and who, 50 years later, revisits these extraordinary times. I emphasize the state of confusion and contradiction but also of extraordinary excitement in which we, earth scientists, lived at this time. I will identify several cases of what I consider to be simultaneous appearances of new ideas and will describe what now appear to be incomprehensible failures to jump on apparently obvious conclusions, based on my own experience.
... In the 1920s to 1930s, submarineborne gravity measurements in the Indonesian region led by Dutch geophysicist F. Vening Meinesz revealed major negative gravity anomalies along the Sumatra-Java-Banda trenches (Umbgrove, 1945) similar to those subsequently recognized to also exist over other deep-sea trenches. Understanding the significance of radioactive heating of Earth, earthquake and igneous activity, and the characteristics of arc-trench systems was critical in development of a convective hypothesis to account for continental drift (Holmes, 1928). However, it was not until the development of the plate tectonic theory (Hess, 1962;Wilson, 1965;McKenzie and Parker, 1967) that the significance of deep-sea trenches and associated earthquakes and volcanism became generally understood to mark the return (subduction) of tectonic plates (portions of lithosphere) into Earth's interior. ...
Article
The association of deep-sea trenches—steeply angled, planar zones where earthquakes occur deep into Earth’s interior—and chains, or arcs, of active, explosive volcanoes had been recognized for 90 years prior to the development of plate tectonic theory in the 1960s. Oceanic lithosphere is created at mid-ocean ridge spreading centers and recycled into the mantle at subduction zones, where down-going lithospheric plates dynamically sustain the deep-sea trenches. Study of subduction zone initiation is a challenge because evidence of the processes involved is typically destroyed or buried by later tectonic and crust-forming events. In 2014 and 2017, the International Ocean Discovery Program (IODP) specifically targeted these processes with three back-to-back expeditions to the archetypal Izu-Bonin-Mariana (IBM) intra-oceanic arcs and one expedition to the Tonga-Kermadec (TK) system. Both subduction systems were initiated ~52 million years ago, coincident with a proposed major change of Pacific plate motion. These expeditions explored the tectonism preceding and accompanying subduction initiation and the characteristics of the earliest crust-forming magmatism. Lack of compressive uplift in the overriding plate combined with voluminous basaltic seafloor magmatism in an extensional environment indicates a large component of spontaneous subduction initiation was involved for the IBM. Conversely, a complex range of far-field uplift and depression accompanied the birth of the TK system, indicative of a more distal forcing of subduction initiation. Future scientific ocean drilling is needed to target the three-dimensional aspects of these processes at new converging margins.
... Plate tectonic theory began to generate more interest throughout the 1960s and previous work in support of the hypothesis was brought to the forefront of earth science research (e.g. Agrand 1924;Wegener 1924;Holmes 1931;Du Toit 1937). In 1966, based on evidence in the fossil record and the dating of vestiges of ancient volcanoes, Wilson proposed a cycle describing the opening and closing of oceanic basins, and therefore a method of amalgamating continental material that would subsequently be dispersed. ...
... They provide an explanation for the subduction of a light and buoyant continental lithosphere into the mantle in a collision context, emphasizing the role of far field forces instead of subduction related forces, typically slab pull. Most importantly, this process obviously rules out slab pull as the omnipotent driver of plate tectonics and calls back to the more ancient conveyor belt view advocated by Holmes (1929). ...
Article
Since several decades, the processes allowing for the subduction of the continental lithosphere less dense than the mantle in a collision context have been widely explored, but models that are based upon the premise that slab pull is the prominent driver of plate tectonics fail. The India–Asia collision, where several episodes of continental subduction have been documented, constitute a case study for alternative views. One of these episodes occurred in the early collision time within the Asian plate where continental lithosphere not attached to any oceanic lithosphere subducted southward in front of the Indian lithosphere during its northward subduction that followed the oceanic subduction of the Tethys ocean. This process, known as collisional subduction, has a counter-intuitive behavior since the subduction is not driven by slab pull. It has been speculated that the mantle circulation can play an important role in triggering collisional subduction but a detailed, qualitative analysis of it is not available, yet. In this work we explore the southward subduction dynamics of the Asian lithosphere below Tibet by means of analogue experiments with the aim to highlight how the mantle circulation induces or responds to collisional subduction. We found that during the northward oceanic subduction (analogue of Tethys subduction) attached to the indenter (Indian analogue), the main component of slab motion is driven vertically by its negative buoyancy, while the trench rolls back. In the mantle the convective pattern consists in a pair of wide convective cells on both sides of the slab. But when the indenter starts to bend and plunge in the mantle, trench motion reverses. Its advance transmits the far field forces to two upper plates (Asian analogues). The more viscous frontal plate thickens, and the less viscous hinterland plate, which is attached to the back wall of the box, subducts. During this transition, a pair of sub-lithospheric convective cells is observed on both sides of the Asian analogue slab, driven by the shortening of the frontal plate. It favors the initiation of the backwall plate subduction. Such subduction is maintained during the entire collision by a wide cell with a mostly horizontal mantle flow below Tibet, passively advecting the Asian analogue slab. Experimental results suggest that once the tectonic far-field force related to the forward horizontal motion becomes dominant upon the buoyancy forces, trench advancing and the transmission of the tectonic force to the upper and backwall plates are promoted. This peculiar condition triggers the subduction of the backwall plate, despite it is light and buoyant.
... Heezen changed his opinion in the mid-60s and died in the nuclear submarine NR-1 collecting data offshore Iceland in 1977. Meanwhile Hess (1962), who had already since the 1930s with Vening-Meinesz explored the Holmes (1930) mantle convection current explanation (cf. Holmes, 1944), produced his view of the earth that soon was labeled seafloor spreading. ...
Article
One of the World's premier field geologists, Kristján Sæmundsson led immense geological mapping programs and authored or co-authored nearly all geological maps of Iceland during the past half century, including the first modern bedrock and tectonic maps of the whole country. These monumental achievements collectively yield the most inclusive view of an extensional plate boundary anywhere on Earth. When Kristján began his work in 1961, the relation of Iceland to sea-floor spreading was not clear, and plate tectonics had not yet been invented. Kristján resolved key obstacles by demonstrating that the active rifting zones in Iceland had shifted over time and were linked by complex transforms to the mid-ocean spreading ridge, thus making the concept of sea-floor spreading in Iceland acceptable to those previously skeptical. Further, his insights and vast geological and tectonic knowledge on both high- and low-temperature geothermal areas in Iceland yielded a major increase in knowledge of geothermal systems, and probably no one has contributed more than he to Icelandic energy development. Kristján's legacy is comprised by his numerous superb maps on a variety of scales, the high quality papers he produced, the impactful ideas generated that were internationally diffused, and the generations of colleagues and younger people he inspired, mentored, or otherwise positively influenced with his knowledge and generous attitude.
... Since the early days of the continental drift theory, the question of the engine of surface displacements and formation of rifts or mountain belts has been discussed in terms of mantle convection (Griggs, 1939;Holmes, 1931;McKenzie, 1969;Runcorn, 1962;Wilson, 1973). More recent models have shown that mantle flow and slab suction are important ingredients to explain plate kinematics (Conrad & Lithgow-Bertelloni, 2002) but deformation within plates is rarely considered in these models (Dal Zilio et al., 2017;Faccenna, Becker, Conrad, et al., 2013;Faccenna, Becker, Jolivet, et al., 2013;Jolivet et al., 2009;Yamato et al., 2013). ...
Article
The formation of mountain belts or rift zones is commonly attributed to interactions between plates along their boundaries, but the widely distributed deformation of Asia from Himalaya to the Japan Sea and other back-arc basins is difficult to reconcile with this notion. Through comparison of the tectonic and kinematic records of the last 50 Ma with seismic tomography and anisotropy models, we show that the closure of the former Tethys Ocean and the extensional deformation of East Asia can be best explained if the asthenospheric mantle transporting India northward, forming the Himalaya and the Tibetan Plateau, reaches East Asia where it overrides the westward flowing Pacific mantle and contributes to subduction dynamics, distributing extensional deformation over a 3,000-km wide region. This deep asthenospheric flow partly controls the compressional stresses transmitted through the continent-continent collision, driving crustal thickening below the Himalayas and Tibet and the propagation of strike-slip faults across Asian lithosphere further north and east, as well as with the lithospheric and crustal flow powered by slab retreat east of the collision zone below East and SE Asia. The main shortening direction in the deforming continent between the collision zone and the Pacific subduction zones may in this case be a proxy for the direction of flow in the asthenosphere underneath, which may become a useful tool for studying mantle flow in the distant past. Our model of the India-Asia collision emphasizes the role of asthenospheric flow underneath continents and may offer alternative ways of understanding tectonic processes.
Chapter
Due to the nature of large-lecture format courses, it is difficult to enact many effective pedagogic strategies large lecture halls provide students a feeling of anonymity, and this has been implicated lower class attendance, reduced student mental engagement, and difficulties in promoting discussions among students and with the instructor. Moreover, authentic assessment strategies–like drawing, writing, and arguing all require more time and effort for evaluation in such large environments. Yet, research overwhelmingly makes clear that class attendance, mental engagement, and meaningful assessment are all associated with robust learning.
Preprint
Full-text available
Plate motion is a remarkable Earth process that is widely ascribed to two primary driving forces: ridge push and slab pull. With the release of the first- and second-order stress fields in 1989, it was found that the observed stresses are mainly distributed on the uppermost brittle part of the lithosphere. A modeling analysis, however, reveals that the stress produced by ridge push is mainly distributed in the lower part of the lithosphere. Doglioni and Panza recently showed that slab pull was inconsistent with the geometry and kinematics of plate. These findings suggest that other force is possibly responsible for plate motion and the observed stress. Here, we propose that the pressure of deep ocean water against the continental wall exerts enormous force (i.e., ocean-generated force) on the continent. The continent is fixed on top of the lithosphere, this attachment allows the ocean-generated force to laterally transfer to the lithospheric plate. We show that this force may combine the ridge push, collisional, and shearing forces to form force balances for the lithospheric plate; the calculated movements for the South American, African, North American, Eurasian, Australian, and Pacific plates are well consistent with the observed movements in both speed and azimuth, the RMS of the calculated speed against the observed speed for these plates is 0.91, 3.76, 2.77, 2.31, 7.43, and 1.95 mm/yr, respectively.
Preprint
Full-text available
Continental rifts can form when and where continents are stretched. If the driving forces can overcome lithospheric strength, a rift valley forms. Rifts are characterised by faults, sedimentary basins, earthquakes and/or volcanism. With the right set of weakening feedbacks, a rift can evolve to break a continent into conjugate rifted margins such as those found along the Atlantic and Indian Oceans. When, however, strengthening processes overtake weakening, rifting can stall and leave a failed rift, such as the North Sea or the West African Rift. A clear definition of continental break-up is still lacking because the transition from continent to ocean can be complex, with tilted continental blocks and regions of exhumed lithospheric mantle. Rifts and rifted margins not only shape the face of our planet, they also have a clear societal impact, through hazards caused by earthquakes, volcanism, landslides and CO2 release, and through their resources, such as fertile land, hydrocarbons, minerals and geothermal potential. This societal relevance makes an understanding of the many unknown aspects of rift processes as critical as ever.
Article
Full-text available
How can the sluggish, long-wavelength mantle convection be expressed by so many time and space scales of morphotectonic activity? To investigate these relationships, we explore the Java-Banda subduction zone, where geodynamic records cluster. In the far-East Tethys, the exceptionally arcuate Banda subduction zone circumscribes the deepest oceanic basin on Earth, seismotectonic activity slices the upper plate more efficiently than anywhere else, and uncommonly vast expanses of continents are flooded in Sundaland and Northern Australia. By comparing numerical simulations of subduction dynamics to a set of independent observations, we reveal the many facets of tectonic and physiographic changes that the sole docking of the Australian continent onto the subduction zone triggered. While mantle flow remains slow and long-wavelength at depth, intense tectonic activity, and dynamic uplift and subsidence profoundly rework the physiography at many spatial scales. These results demonstrate that a modest disruption in the slow geodynamic tempo may trigger manifold morphotectonic disturbances.
Article
rogeny results from crustal thickening at active margins, and much progress has been made on understanding the associated kinematics. However, the ultimate cause of orogeny is still debated, especially for the case of extreme crustal thickening. Inspired by the seminal work of Holmes (1931), we explore the connections between the style of orogeny and mantle dynamics. We distinguish between two types of orogeny, those that are associated with one- sided, mainly upper mantle subduction, "slab-pull orogeny", and those related to more symmetric, whole mantle convection cells, referred to as "mantle", or "slab-suction orogeny". Only the latter leads to extreme crustal thickening. We propose that mantle orogeny is generated by the penetration of slabs into the lower mantle and the associated change in the length scales of convection. This suggestion is supported by numerical dynamic models which show that upper plate compression is associated with slab penetration into the lower mantle. Slabs can further trigger a buoyant, plume upwelling from the core-mantle boundary which enhances this whole mantle convection cell, and with it upper plate compression. We explore the geological record to test the validity of such a model. For the present-day, compressional backarc regions are commonly associated with slabs that subduct to the deep lower mantle. The temporal evolution of the Nazca and Tethyan slabs with the associated Andean Cordillera and the Tibetan-Himalayan orogenies likewise suggests that extreme crustal thickening below the Bolivia and Tibetan plateau occurred during slab penetration into the lower mantle. This episode of crustal thickening in the Tertiary bears similarity with Pangea assembly events, where the Gondwanide accretionary orogen occurred at the same time of the Variscan-Appalachian and Ural orogeny. We propose that this Late Paleozoic large-scale compression is likewise related to a change from transient slab ponding in the transition zone to lower mantle subduction. If our model is correct, the geological record of orogeny in continental lithosphere can be used to decipher time- dependent mantle convection, and episodic lower mantle subduction may be causally related to the supercontinental cycle.
Presentation
Full-text available
Reviewer's comments: The problem discussed is interesting and current (see e. g. Zaccagnino et al., 2020). Unfortunately, the author's reasoning is quite difficult to follow. Too many issues are discussed in one study. It is unfortunate to link the issue of plate motion to unfounded earthquake predictions. In my view, it is incorrect to claim that mantle convection “contradicts to any observations” (lines 11,12 and also at and other places). Earthquake tomography, magnetic anomalies observed on ocean plates, the remarkably young age of the ocean floor in any case make convection probable. It is true, however, that with convection it is difficult to explain the motion of tectonic plates. I think the study needs a major revision and should be re-submitted as a new article after that. I have found inaccuracies in various places in what the author writes about tidal waves. I would focus on lines 20-23 first. The effect of Mf declinational zonal wave is significantly larger than the impact of the Mm elliptic one and also input of solar Ssa declinational wave has a more or less similar magnitude. Sectorial semi-diurnal waves are not variants of zonal waves and have no effect on the rotation of the Earth, as far as the earth tides are considered. Tides play a significant role in changes in length of day (LOD), but their impact is not dominant (see lines 48-49). Oceanic and especially atmospheric angular momentums are more significant. To answer this objection, tidal forces acting on lithospheric plates are calculated on Appendix (Calculations of tidal forces). This paragraph presents formulas calculating tidal forces for given parameters of Moon and Sun positions. It is true that globally aangular momentum fluctuations of the atmosphere and changes in the length of the day (Hide 1984) have very similar graph. However just details of LOD graph presents in many cases the tool to proof the earthquakes tidal origin. I found a number of incorrect or unsupported statements: - why there is subduction only in the northern hemisphere? (line 95) - Plates move only northward, because after the decay og Gondwana, the oddest and heaviest oceanic litgosphere remained along southerm rim of Laurasia, prone to subduct by gravity descent. - what is the source of numbers in line 102? - Numbers on periodic curve of figure are maximum and minimum stresses acting on equatorial lithosphere calculated from equation (2) of Appendix with periodic addition or subtraction of stress of Sun (eqution 1). - the sectorial M2 wave has no effect on LOD (line 104). LOD can be influenced only by zonal tidal waves - This is true but on lithosphere act both forces zonal equator flying and westward drift. - why is absolute nonsense the mantle convection? (line 121) - Mantle convection contradicts to any real imaginations. Arguments presented in first 7 columns of the paper try to confirm this statement. The next column “Acttion of tides on Earth” present tides as dominant force moving plates. - “mid-ocean ridges are opened by tides” (line 133) - Of course by moving plates driven by tides. - “hotspots are simple strikes of oceanic lithosphere by meteorites” (line 150) Only impact of meteorites can create point sources of ascending magma for hotspots. - In spite of presented impossibility of mantle convection, reviewer is still not satisfied with explanation. First, hotspots are firmly fixed in mantle and therefore hotspot tracks direct in opposite direction from mid-ocean ridge. In case of mantle convection hotspot tracks would direct towards mid-ocean ridge. Mantle forms a firm and solid carapace around liquid core. Ascent any hot mantle plumes is impossible unless any cracks occur in mantle bottom facilitating the plume ascent. These ascents never can be a point sources, as in reality are but linear or curvilinear features on Earth’s surface. Mantle plimes are point sources of different size produced by meteoric impact protruding oceanic lithosphere and splinter on continental lithosphere. Meteoritic mantle plume is heated by surrounding hot mantle but inside is melted because its solid consistence prevent any action of pressure increasing according to Clausius Clappeyron equation melting point and light component uprise and heavy component descends. Similar effect is evident in subdction. Solid descending oceanic lithosphere is not affected by the increase of pressure but heated by surrounding environment (effect of bathyscaphe produced from strong steel). Cracks occur on both sides of subduction zone but melted part is inside. Light material uprise forming island arc volcanics and heavy part descends and burns a hole in mantle.It is really hardly to imagine how againat upword streaming magma of back-arc basin volcanics mantle convection drive oceanic lithosphere down ward. - the text of the article does not explain why the plates move westwards (e.g. line 214), although it is acceptable - Simple explanation of westward movement follows from Eartth’s deceleration caused by tidal friction (Lambeck 1977) and Fig. 1 confirms almost exact westward movement of American and Eurasian plates. Other plate have components of northward and southward movements depicted on Fig. 3. This figure depicts components of the plate movement with arrows. Points mark Euler’s poles, what in previous studies was recomended to find origin of the plate movement (Ostřihanský, 1997) explained why “steady-state heat conduction the only reasonable” (line 272), this finding is probably incorrect In 1988 I preformed comprehensive study of relation between heat flow and heat production in Bohemian massif. (Ostřihanský, 1988) I found vry low heat flow comming from depth 17.7 mW/m2 whereas heat flow fmeasured above batholiths ranged from 60 – 80 mw/m2 owing to heat production from radioactive eleents 2 – 8 μW/m3. On the other hand in Bohemian massif exist volcannics of young age, for example Komorni Hurka (in German Kammerbühl) finished its activity only 10,000 years ago. For he first time I realized that the opening of volcano was crossing of tectonic faults Krusne Hory and Sudets and therefore external force opened this volcanu, i.e. tides. Result: Heat flow from mantle is low probably constant and volcanism and rapid heatflow increment is caused by tides, This concerns also oceans where created oceanic litthospher carries heat from opened faults. Kmorni Hurka is well known volcano where volcanic origin of basalt has been provenn and opinions of neptunists rejected. (Meeting of J.W. Goethe with Sweedish chemist J J. Berzelius in 18th century) - what means “earth rotation tide”? (line 316). Did you mean the zonal tide? - Table 1 is taken from Yoder’s paper “Tidal variations of Earth rotation, i.e. rotational tides., they are zonal tides. - Table 1, what does the negative period in the top two rows mean? Are the amplitudes in the right-hand column in seconds? - The Yoder’s et al. table from which data from Table 1 are taken has headline: Periodic Series for –ΔUT1, it means that positive values of Amplitudes are decelerating variations and negative accelerating variations. Periods are positive with exception of nodal periods which are negative owing to negative nodal movement. Therefore half nodal amplitudes are in fact positive but nodal period with highest amplitude is negative and for this reason in Zaccagnino et al., graphs nodal amplitude is not evident directing to negative values. Earthquakes in Italy (apart from the Alps region) are characterized by the Apennines (in one zone) and by a parallel to this but with deeper focal depths to the east. The paper contains a selection of earthquakes from this area, but omits some important events: Molise (2002 M5.9), Irpina (1980 M6.9), Emilia-Romagna (2012 M6.1), Abruzo (1884 M5.9). In region of Colfiorito three quakes occurred within a month (M5.3, M6.0 and M5.6). Unfortunately, the correlation with the zonal tidal wave Mf, based on so small amount of data, and cannot be considered statistically established. In the present situation, these are only coincidences. Unfortunately, a similar finding can be made for the other earthquake zones examined by the Author. Table on Fig. 7 does not show earthquakes magnitude but number of earthquakes. Tides are not responsible for earthquakes magnitude, this is affected by material properties prone to trigger earthquake. Number of earthquakes better characterizes tidal influence. Regarding the data used in the article: the source of the LOD data and the seismological data are not specified in all cases. Length of day variations are taken from IERS (Earth rotation service) http://hpiers.obspm.fr/eop-pc/ Moon and Sun declinations from Sun & Moon position Calculator on Internet, Moon phases from Internet. Earthquakes data for Sumatra, Sulawesi and Italy are taken from ANSS Catalog and EMSC Catalog. For California A 15 year catalog of more than 1 million low-frequency earthquakes was taken. Minor comments: - enter please the reference to the Figure 1 Figure 1 comes from Ostřihanský, L., 1997. The causes of lithospheric plates movements, Charles University Prague, Chair of Geography and Geoecology, 64 pp - lines 98 and 99: the source of the data given in Nm? - Data are in Nm (Newton metre) equivalent to J Joule. - Figure 2 is obviously incorrect or incomplete - It is not my foult that Fugure 2 in Elsevier’s PDF was performed incorrectly. Figure 7 is given correctly in separate file at the end of paper. - line 104: 12. 4 h is the period of the M2 wave? - Yes, more exactly 12.42 h. - Figure 3: explain please in the caption to figure the meanings of parallel short lines and “inverse L letters” - Parallel lines mark northward and westward components of the plates movement. Arrows should be placed on northward and westward end of components. - line 272: heat flow Steady-state heat conduction in mantle is the only reasonable explanation of the heat flow on the Earth. It follows from my observatiions (Ostrihansky, Tectonophysics 68, 1980, 325-337) - line 295: Let us - I must mention that mantle convection has its…..…. - Figure 8: the source of the earthquake used should be given - Earthquakes in Fig. 8 are taken from ANSS Catalog over 3 rd magnitude from period of very high Earth rotation 2002 – 2004 (minimum of LOD marked by (e) on Fig. 7. Moon’s position on its orbit has been simply found plotting earthquakes on LOD graph and counting number of days between two LOD maximums for every earthquake, foror both positive and negative declination part of LOD graph. This is the simplest and quickest proof of earthquakes triggering by tides. - Figure 10: caption is incomplete - Caption is complete but Elsevier’s PDF made in addition part of Fig. 10. - Figure 17: the graphics at the top and bottom of the figure are different - LOD variations have dark and light blue colour and different extent of the scale. Mark for conclusion It is interesting how many incorrect hypotheses has been presented since of 18th century to present. They are for example: Antoniadi’s Mars canals, Volcanic origin of Moon’s craters, Neptunists imagination of water effect creating volcanics, Origin of meteorites in atmosphere, Rejecting of plate movements in spite that 1596 Ortelius mentioned continental fit. Wegener’s Polflucht, whereas Equator fleeing is correct. Rejecting earthquakes triggering by tides (Vidale, Agnew) Mantle convection driving plates. Mantle plumes originating in mantle core boundary. The Earth not imaginary body but piece of stone heated from inside. Forces moving plates can be imagined by pneumatic hammer mechanism and mantle plumes by bathyscaphe effect.
Presentation
Full-text available
Mantle convection in Earth interior contradicts to any geological observations. Mantle convection and seemingly chaotic plate movements disqualified any possibilities of earthquake predictions. Earthquakes are triggered during Full or New Moon owing to summarizing action of Moon and Sun torques but relatively scarcely. Mostly, Moon and Sun’s torques are subtracted, what decreases probability of earthquakes triggering. Low declinations and from it Moon and Sun low torques also decreases probability of earthquakes triggering. However high tidal torque of Moon, without support of Sun, very often triggers earthquakes
Chapter
Full-text available
This volume covers new developments and research on mass extinctions, volcanism, and impacts, ranging from the ancient Central Iapetus magmatic province linked with the Gaskiers glaciation to thermogenic degassing in large igneous provinces, the global mercury enrichment in Valanginian sediments, and the Guerrero-Morelos carbonate platform response to the Caribbean-Colombian Cretaceous large igneous province. This section is followed by a series of end-Cretaceous studies, including the implications for the Cretaceous-Paleogene boundary event in shallow platform environments and correlation to the deep sea; the role of wildfires linked to Deccan volcanism on ecosystems from the Indian subcontinent; rock magnetic and mineralogical study of Deccan red boles; and factors leading to the collapse of producers during Deccan Traps eruptions and the Chicxulub impact.
Chapter
Among the many structural features appearing throughout the Universe, including the Earth and its surrounding layers, the attention of contemporary scientists is drawn to the spontaneous structuring of these natural systems and the geometric commonality of the emerging structural forms, i.e., in terms of their cellular (square, hexagonal, polygonal) geometry. The structural similarity of these forms is revealed to be independent of the nature and scale of their manifestation, a factor having already been emphasised by many researchers from a philosophical perspective (V. V. Piotrovsky, M. A. Sadovsky, Yu. M. Pushcharovsky, V. E. Khain, L. I. Krasny, etc.). This has led the scientific community towards the view that the external manifestations of the spontaneous structuring and redistribution of masses in nonequilibrium density distribution in natural systems may be explained in terms of a transphenomenal physical mechanism. This perception is strengthened still further by turning to the applied natural scientific fields of fluid dynamics and thermodynamics, oceanology, meteorology and geophysics, where the same geometric commonality of spontaneous structuring can be seen as underlying otherwise apparently scattered examples.
Article
Full-text available
The article comprehensively presents little known Estonian contribution to the recognition of first meteorite impact structures in Europe, related to works of Julius Kaljuvee (Kalkun; 1869–1940) and Ivan Reinwald (Reinwaldt; 1878–1941). As an active educator specialized in geoscience, Kaljuvee was the first to hypothesize in 1922 that Kaali lake cirque in Saaremaa Island, Estonia, was created by meteorite impact. Thanks to mining engineer Reinwald, this assumption was accepted since 1928 due to the exhaustive field and borehole works of the latter (also as a result of exploration by several German scholars, including renowned Alfred Wegener). The impact origin of Kaali structure was proved finally in 1937 by finding of meteoritic iron splinters (as the first European site). Reinwald was not only outstanding investigator of meteorite cratering process, but also successful propagator of the Estonian discoveries in Anglophone mainstream science in 1930s. In addition, in his 1933 book, Kaljuvee first highlighted an impact explanation of enigmatic Ries structure in Bavaria, as well as probable magmatic activation in distant regions due to “the impulse of a giant meteorite”. He also outlined ideas of the inevitable periodic cosmic collisions in geological past (“rare event” theory nowadays), and resulting biotic crises. In a general conceptual context, the ideas of Kaljuvee were in noteworthy direct or indirect link with concepts of the great French naturalists – Laplace, Cuvier and Élie de Beaumont. However, some other Kaljuvee’s notions, albeit recurrent also later in geoscientific literature, are queer at the present time (e.g., the large-body impact as a driving force of continental drift and change the Earth axis, resulting in the Pleistocene glaciation). Thus, the Kaljuvee thought-provocative but premature dissertation is rather a record of distinguishing erudite activity, but not a real neocatastrophic landmark in geosciences history. Nevertheless, several concepts of Kaljuvee were revived as the key elements in the current geological paradigm.
ResearchGate has not been able to resolve any references for this publication.