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Gwenn Peron-pinvidic - One of the best experts on this subject based on the ideXlab platform.
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The Norway Basin revisited: From Continental Breakup to spreading ridge extinction
Marine and Petroleum Geology, 2012Co-Authors: Laurent Gernigon, Gwenn Peron-pinvidic, Carmen Gaina, Odleiv Olesen, Philip Ball, Tadashi YamasakiAbstract:Abstract We re-evaluate the structure and spreading evolution of the southeastern Norway Basin (NB) based on a new high resolution aeromagnetic survey (NB-07). The survey covers a complete oceanic spreading segment from the Continental–oceanic transition of the More margin, off Norway to the aborted Aegir Ridge. The new survey documents a transform margin, an orthogonally rifted segment and an oblique-sheared volcanic margin formed during the onset of Breakup, observed from the East Jan Mayen Fracture Zone to the Faroe Platform. The detailed fabric of the NB revealed by the new data indicates that two distinct tectonic phases have reshaped the basin before the cessation of seafloor spreading and abortion of the Aegir Ridge in the Late Oligocene. After Continental Breakup, Phase I (from C24 to C21r, ∼52 to 49 Ma) marks the earliest phase of spreading, probably initiated in the central and outer part of the More Basin. During this period, competing oceanic segments led to the formation of overlapping systems and pseudo-fault development. We observe a significant change in the NB's oceanic spreading system in the late Early Eocene and, based on observations from surrounding areas, we suggest that this is a record of a major tectonic event in the Norwegian–Greenland Sea around C21r (49–47.9 Ma). During Phase II (from C21r to C10?, 48 to 28 Ma) of NB's development, spreading rates decreased, spreading direction changed, and the number of faulting with large displacement increased leading to the formation of unexpected N–S oriented oceanic fracture zones. The fan-shaped development of the spreading system initiated around C21r (∼49–47.9 Ma) instead of C18–C17 (∼40–38 Ma) or C24 (53.3–52.3 Ma) as previously proposed. These new observations were used to re-evaluate the tectonic evolution of the Norwegian–Greenland Sea and discuss some implications on the syn- and post-Breakup development of the surrounding Continental margins and the evolution of the Jan Mayen microcontinent.
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Magmatic Breakup as an explanation for magnetic anomalies at magma-poor rifted margins
Nature Geoscience, 2011Co-Authors: A. Bronner, Daniel Sauter, Gianreto Manatschal, Gwenn Peron-pinvidic, Marc MunschyAbstract:During Continental Breakup, the onset of seafloor spreading is thought to be marked by the first occurrence of a magnetic anomaly. Analysis of seismic and magnetic data from the Iberia–Newfoundland Continental-rift system suggests that the first magnetic anomaly observed here instead represents a magmatic event that pre-dates seafloor spreading.
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The lesson from the Iberia-Newfoundland rifted margins: how applicable is it to other rifted margins?
2010Co-Authors: Gianreto Manatschal, Emilie Sutra, Gwenn Peron-pinvidicAbstract:The Iberia-Newfoundland rifted margins represent a unique data set to study the structure and processes related to rifting and Continental Breakup in magma-poor rifted margins. The major observations made along these margins show that: 1) rifting is polyphase and deformation localizes and migrates towards the area of final Breakup, 2) the mantle consists of inherited, infiltrated and depleted domains, and 3) magmatism includes infiltration, underplating, diking and extrusion of MOR and alkaline magmas before, during and after Continental Breakup. This complex polyphase evolution is recorded in the migration of syn-tectonic sedimentary sequences and a subsidence history, which is yet little understood. These observations enable us to propose and test new models for the formation of deep-water rifted margins and Continental break-up. A key question is to what extend the observations and models derived from the Iberia-Newfoundland rifted margins can be compared with less explored rift systems.
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Assessing the conditions of Continental Breakup at magma-poor rifted margins: what can we learn from slow-spreading mid-ocean ridges ?
2009Co-Authors: Mathilde Cannat, Daniel Sauter, Gianreto Manatschal, Gwenn Peron-pinvidicAbstract:We propose a review of the tectonic, magmatic and hydrothermal evolution of slow spreading ridges, focusing on concepts which we think are most relevant to discuss the rift to drift transition at magma-poor ocean–continent transitions (OCTs). Based on this review, we emphasize the importance of the thermal regime as a key parameter and we propose that the thermal regime of magma-poor OCTs evolves in the following principal phases: the onset of decompression mantle melting, the onset of localized plate divergence, the installation of a ridge-type thermal regime (active heat balance, no inheritance), which we argue is the most practical definition for Continental Breakup, and, possibly, the onset of ridge-type, focused mantle upwelling. We propose this phased evolution as a framework in which to develop further research, combining our understanding of rifting and seafloor spreading, in order to better quantify the processes that control Continental Breakup. To cite this article: M. Cannat et al., C. R. Geoscience xxx (2009).
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Assessing the conditions of Continental Breakup at magma-poor rifted margins: What can we learn from slow spreading mid-ocean ridges?
Comptes Rendus Geoscience, 2009Co-Authors: Mathilde Cannat, Daniel Sauter, Gianreto Manatschal, Gwenn Peron-pinvidicAbstract:Abstract We propose a review of the tectonic, magmatic and hydrothermal evolution of slow spreading ridges, focusing on concepts which we think are most relevant to discuss the rift to drift transition at magma-poor ocean–continent transitions (OCTs). Based on this review, we emphasize the importance of the thermal regime as a key parameter and we propose that the thermal regime of magma-poor OCTs evolves in the following principal phases: the onset of decompression mantle melting, the onset of localized plate divergence, the installation of a ridge-type thermal regime (active heat balance, no inheritance), which we argue is the most practical definition for Continental Breakup, and, possibly, the onset of ridge-type, focused mantle upwelling. We propose this phased evolution as a framework in which to develop further research, combining our understanding of rifting and seafloor spreading, in order to better quantify the processes that control Continental Breakup.
Nicolas Espurt - One of the best experts on this subject based on the ideXlab platform.
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interactions between Continental Breakup dynamics and large scale delta system evolution insights from the cretaceous ceduna delta system bight basin southern australian margin
Tectonics, 2009Co-Authors: Nicolas Espurt, Jean-paul Callot, Jennifer Totterdell, Heike Struckmeyer, Roland ViallyAbstract:[1] The interpretation of two regional seismic reflection profiles and the construction of a balanced cross section through the southern Australian margin (Bight Basin) are designed to analyze the influence of the Australia-Antarctica Continental Breakup process on the kinematic evolution of the Cretaceous Ceduna delta system. The data show that the structural architecture of this delta system consists of two stacked delta systems. The lower White Pointer delta system (Late Albian-Santonian) is an unstable tectonic wedge, regionally detached seaward above Late Albian ductile shales. Sequential restoration suggests that the overall gravitational sliding behavior of the White Pointer delta wedge (∼45 km of seaward extension, i.e., ∼27%) is partially balanced by the tectonic denudation of the subContinental mantle. We are able to estimate the horizontal stretching rate of the mantle exhumation between ∼2 and 5 km Ma−1. The associated uplift of the distal part of the margin and associated flexural subsidence in the proximal part of the basin are partially responsible for the decrease of the gravitational sliding of the White Pointer delta system. Lithospheric failure occurs at ∼84 Ma through the rapid exhumation of the mantle. The upper Hammerhead delta system (Late Santonian-Maastrichtian) forms a stable tectonic wedge developed during initial, slow seafloor spreading and sag basin evolution of the Australian side margin. Lateral variation of basin slope (related to the geometry of the underlying White Pointer delta wedge) is associated with distal raft tectonic structures sustained by high sedimentation rates. Finally, we propose a conceptual low-angle detachment fault model for the evolution of the Australian-Antarctic conjugate margins, in which the Antarctic margin corresponds to the upper plate and the Australian margin to the lower plate.
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Interactions between Continental Breakup dynamics and large‐scale delta system evolution: Insights from the Cretaceous Ceduna delta system, Bight Basin, Southern Australian margin
Tectonics, 2009Co-Authors: Nicolas Espurt, Jean-paul Callot, Jennifer Totterdell, Heike Struckmeyer, Roland ViallyAbstract:[1] The interpretation of two regional seismic reflection profiles and the construction of a balanced cross section through the southern Australian margin (Bight Basin) are designed to analyze the influence of the Australia-Antarctica Continental Breakup process on the kinematic evolution of the Cretaceous Ceduna delta system. The data show that the structural architecture of this delta system consists of two stacked delta systems. The lower White Pointer delta system (Late Albian-Santonian) is an unstable tectonic wedge, regionally detached seaward above Late Albian ductile shales. Sequential restoration suggests that the overall gravitational sliding behavior of the White Pointer delta wedge (∼45 km of seaward extension, i.e., ∼27%) is partially balanced by the tectonic denudation of the subContinental mantle. We are able to estimate the horizontal stretching rate of the mantle exhumation between ∼2 and 5 km Ma−1. The associated uplift of the distal part of the margin and associated flexural subsidence in the proximal part of the basin are partially responsible for the decrease of the gravitational sliding of the White Pointer delta system. Lithospheric failure occurs at ∼84 Ma through the rapid exhumation of the mantle. The upper Hammerhead delta system (Late Santonian-Maastrichtian) forms a stable tectonic wedge developed during initial, slow seafloor spreading and sag basin evolution of the Australian side margin. Lateral variation of basin slope (related to the geometry of the underlying White Pointer delta wedge) is associated with distal raft tectonic structures sustained by high sedimentation rates. Finally, we propose a conceptual low-angle detachment fault model for the evolution of the Australian-Antarctic conjugate margins, in which the Antarctic margin corresponds to the upper plate and the Australian margin to the lower plate.
Roland Vially - One of the best experts on this subject based on the ideXlab platform.
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interactions between Continental Breakup dynamics and large scale delta system evolution insights from the cretaceous ceduna delta system bight basin southern australian margin
Tectonics, 2009Co-Authors: Nicolas Espurt, Jean-paul Callot, Jennifer Totterdell, Heike Struckmeyer, Roland ViallyAbstract:[1] The interpretation of two regional seismic reflection profiles and the construction of a balanced cross section through the southern Australian margin (Bight Basin) are designed to analyze the influence of the Australia-Antarctica Continental Breakup process on the kinematic evolution of the Cretaceous Ceduna delta system. The data show that the structural architecture of this delta system consists of two stacked delta systems. The lower White Pointer delta system (Late Albian-Santonian) is an unstable tectonic wedge, regionally detached seaward above Late Albian ductile shales. Sequential restoration suggests that the overall gravitational sliding behavior of the White Pointer delta wedge (∼45 km of seaward extension, i.e., ∼27%) is partially balanced by the tectonic denudation of the subContinental mantle. We are able to estimate the horizontal stretching rate of the mantle exhumation between ∼2 and 5 km Ma−1. The associated uplift of the distal part of the margin and associated flexural subsidence in the proximal part of the basin are partially responsible for the decrease of the gravitational sliding of the White Pointer delta system. Lithospheric failure occurs at ∼84 Ma through the rapid exhumation of the mantle. The upper Hammerhead delta system (Late Santonian-Maastrichtian) forms a stable tectonic wedge developed during initial, slow seafloor spreading and sag basin evolution of the Australian side margin. Lateral variation of basin slope (related to the geometry of the underlying White Pointer delta wedge) is associated with distal raft tectonic structures sustained by high sedimentation rates. Finally, we propose a conceptual low-angle detachment fault model for the evolution of the Australian-Antarctic conjugate margins, in which the Antarctic margin corresponds to the upper plate and the Australian margin to the lower plate.
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Interactions between Continental Breakup dynamics and large‐scale delta system evolution: Insights from the Cretaceous Ceduna delta system, Bight Basin, Southern Australian margin
Tectonics, 2009Co-Authors: Nicolas Espurt, Jean-paul Callot, Jennifer Totterdell, Heike Struckmeyer, Roland ViallyAbstract:[1] The interpretation of two regional seismic reflection profiles and the construction of a balanced cross section through the southern Australian margin (Bight Basin) are designed to analyze the influence of the Australia-Antarctica Continental Breakup process on the kinematic evolution of the Cretaceous Ceduna delta system. The data show that the structural architecture of this delta system consists of two stacked delta systems. The lower White Pointer delta system (Late Albian-Santonian) is an unstable tectonic wedge, regionally detached seaward above Late Albian ductile shales. Sequential restoration suggests that the overall gravitational sliding behavior of the White Pointer delta wedge (∼45 km of seaward extension, i.e., ∼27%) is partially balanced by the tectonic denudation of the subContinental mantle. We are able to estimate the horizontal stretching rate of the mantle exhumation between ∼2 and 5 km Ma−1. The associated uplift of the distal part of the margin and associated flexural subsidence in the proximal part of the basin are partially responsible for the decrease of the gravitational sliding of the White Pointer delta system. Lithospheric failure occurs at ∼84 Ma through the rapid exhumation of the mantle. The upper Hammerhead delta system (Late Santonian-Maastrichtian) forms a stable tectonic wedge developed during initial, slow seafloor spreading and sag basin evolution of the Australian side margin. Lateral variation of basin slope (related to the geometry of the underlying White Pointer delta wedge) is associated with distal raft tectonic structures sustained by high sedimentation rates. Finally, we propose a conceptual low-angle detachment fault model for the evolution of the Australian-Antarctic conjugate margins, in which the Antarctic margin corresponds to the upper plate and the Australian margin to the lower plate.
John R. Hopper - One of the best experts on this subject based on the ideXlab platform.
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COBBOOM: The Continental Breakup and Birth of Oceans Mission
Scientific Drilling, 2007Co-Authors: Dale S. Sawyer, Joann M Stock, Millard F. Coffin, Timothy J. Reston, John R. HopperAbstract:The rupture of continents and creation of new oceans is a fundamental yet primitively understood aspect of the plate tectonic cycle. Building upon past achievements by ocean drilling and geophysical and geologic studies, we propose “The Continental Breakup and Birth of Oceans Mission (COBBOOM)” as the next major phase of discovery, for which sampling by drilling will be essential. In September 2006, fifty-one scientists from six continents gathered in Pontresina, Switzerland to discuss current knowledge of Continental Breakup and sedimentary basin formation and how the Integrated Ocean Drilling Program (IODP) can deepen that knowledge (Coffin et al., 2006). Workshop participants discussed a global array of rifted margins (Fig. 1), formulated the critical problems to be addressed by future drilling and related investigations, and identified key rift systems poised for IODP investigations.
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COBBOOM: The Continental Breakup and Birth of Oceans Mission
Scientific Drilling, 2007Co-Authors: Dale S. Sawyer, Millard F. Coffin, T. J. Reston, J. M. Stock, John R. HopperAbstract:No abstract available. <br><br> doi:<a href="http://dx.doi.org/10.22 04/iodp.sd.5.02.2007" target="_blank">10.22 04/iodp.sd.5.02.2007</a>
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from rift to drift mantle melting during Continental Breakup
Geochemistry Geophysics Geosystems, 2004Co-Authors: Thomas K Nielsen, John R. HopperAbstract:[1] Volcanic rifted margins show a temporal evolution in igneous crustal thickness and thus provide additional insights into mantle dynamics compared to the steady state situation at mid-ocean ridges. Although details between different provinces vary, volcanic rifted margins generally show a short-lived pulse of extreme magmatism that quickly abates to a steady state mid-ocean ridge. The generation of thick igneous crust at volcanic rifted margins requires either melting of hot mantle material to higher degrees than observed at mid-ocean ridges or melting of larger amounts of mantle material than would be the case for plate-driven upwelling. To assess under what conditions buoyantly driven upwelling or small-scale convection at rifting plate boundaries is important, a fluid dynamical model with non-Newtonian viscosity that includes the feedback from melting on the physical properties of the mantle is developed. To generate a pulse of high magmatic production requires a viscosity and density structure that also leads to excessive fluctuations in magmatic productivity or a sustained high productivity that continues long after Breakup. A viscosity increase due to dehydration caused by melting effectively suppresses buoyant upwelling above the depth to the dry solidus, thereby restricting shallow flow to plate-driven upwelling. While this stabilizes the time dependence and forces the productivity to values consistent with mid-ocean ridge accretion, it does so at the expense of eliminating the Breakup instability. Models that assume an abrupt change in prerift lithospheric thickness suffer from the same deficits. However, including a sublithospheric hot layer leads to a model that can predict the temporal evolution of igneous crustal thickness observed in refraction seismic data from the southeast Greenland volcanic rifted margin.
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Mantle thermal structure and active upwelling during Continental Breakup in the North Atlantic
Earth and Planetary Science Letters, 2001Co-Authors: W. Steven Holbrook, H C Larsen, John R. Hopper, Jun Korenaga, Trine Dahl-jensen, I.d. Reid, Peter B. Kelemen, Graham M. Kent, Daniel Lizarralde, Stefan BernsteinAbstract:Seismic reflection and refraction data acquired on four transects spanning the Southeast Greenland rifted margin and Greenland^Iceland Ridge (GIR) provide new constraints on mantle thermal structure and melting processes during Continental Breakup in the North Atlantic. Maximum igneous crustal thickness varies along the margin from s 30 km in the near-hotspot zone (6 500 km from the hotspot track) to V18 km in the distal zone (500^1100 km). Magmatic productivity on summed conjugate margins of the North Atlantic decreases through time from 1800 ˛ 300 to 600 ˛ 50 km 3 /km/Ma in the near-hotspot zone and from 700 ˛ 200 to 300 ˛ 50 km 3 /km/Ma in the distal zone. Comparison of our data with the British/Faeroe margins shows that both symmetric and asymmetric conjugate volcanic rifted margins exist. Joint consideration of crustal thickness and mean crustal seismic velocity suggests that along-margin changes in magmatism are principally controlled by variations in active upwelling rather than mantle temperature. The thermal anomaly (vT) at Breakup was modest (V100^125‡C), varied little along the margin, and transient. Data along the GIR indicate that the potential temperature anomaly (125 ˛ 50‡C) and upwelling ratio (V4 times passive) of the Iceland hotspot have remained roughly constant since 56 Ma. Our results are consistent with a plume^impact model, in which (1) a plume of radius V300 km and vT of V125‡C impacted the margin around 61 Ma and delivered warm material to distal portions of the margin; (2) at Breakup (56 Ma), the lower half of the plume head continued to feed actively upwelling mantle into the proximal portion of the margin; and (3) by 45 Ma, both the remaining plume head and the distal warm layer were exhausted, with excess magmatism thereafter largely confined to a narrow (6 200 km radius) zone immediately above the Iceland plume stem. Alternatively, the warm upper mantle layer that fed excess magmatism in the distal portion of the margin may have been a pre-existing thermal anomaly unrelated to the plume. fl 2001 Elsevier Science B.V. All rights reserved.
H C Larsen - One of the best experts on this subject based on the ideXlab platform.
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rapid transition from Continental Breakup to igneous oceanic crust in the south china sea
Nature Geoscience, 2018Co-Authors: H C Larsen, G Mohn, M Nirrengarten, Joann M Stock, Z Jian, A Klaus, C A Alvarezzarikian, Jacopo Boaga, S A BowdenAbstract:Continental Breakup represents the successful process of rifting and thinning of the Continental lithosphere, leading to plate rupture and initiation of oceanic crust formation. Magmatism during Breakup seems to follow a path of either excessive, transient magmatism (magma-rich margins) or of igneous starvation (magma-poor margins). The latter type is characterized by extreme Continental lithospheric extension and mantle exhumation prior to igneous oceanic crust formation. Discovery of magma-poor margins has raised fundamental questions about the onset of ocean-floor type magmatism, and has guided interpretation of seismic data across many rifted margins, including the highly extended northern South China Sea margin. Here we report International Ocean Discovery Program drilling data from the northern South China Sea margin, testing the magma-poor margin model outside the North Atlantic. Contrary to expectations, results show initiation of Mid-Ocean Ridge basalt type magmatism during Breakup, with a narrow and rapid transition into igneous oceanic crust. Coring and seismic data suggest that fast lithospheric extension without mantle exhumation generated a margin structure between the two endmembers. Asthenospheric upwelling yielding Mid-Ocean Ridge basalt-type magmatism from normal-temperature mantle during final Breakup is interpreted to reflect rapid rifting within thin pre-rift lithosphere.
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Mantle thermal structure and active upwelling during Continental Breakup in the North Atlantic
Earth and Planetary Science Letters, 2001Co-Authors: W. Steven Holbrook, H C Larsen, John R. Hopper, Jun Korenaga, Trine Dahl-jensen, I.d. Reid, Peter B. Kelemen, Graham M. Kent, Daniel Lizarralde, Stefan BernsteinAbstract:Seismic reflection and refraction data acquired on four transects spanning the Southeast Greenland rifted margin and Greenland^Iceland Ridge (GIR) provide new constraints on mantle thermal structure and melting processes during Continental Breakup in the North Atlantic. Maximum igneous crustal thickness varies along the margin from s 30 km in the near-hotspot zone (6 500 km from the hotspot track) to V18 km in the distal zone (500^1100 km). Magmatic productivity on summed conjugate margins of the North Atlantic decreases through time from 1800 ˛ 300 to 600 ˛ 50 km 3 /km/Ma in the near-hotspot zone and from 700 ˛ 200 to 300 ˛ 50 km 3 /km/Ma in the distal zone. Comparison of our data with the British/Faeroe margins shows that both symmetric and asymmetric conjugate volcanic rifted margins exist. Joint consideration of crustal thickness and mean crustal seismic velocity suggests that along-margin changes in magmatism are principally controlled by variations in active upwelling rather than mantle temperature. The thermal anomaly (vT) at Breakup was modest (V100^125‡C), varied little along the margin, and transient. Data along the GIR indicate that the potential temperature anomaly (125 ˛ 50‡C) and upwelling ratio (V4 times passive) of the Iceland hotspot have remained roughly constant since 56 Ma. Our results are consistent with a plume^impact model, in which (1) a plume of radius V300 km and vT of V125‡C impacted the margin around 61 Ma and delivered warm material to distal portions of the margin; (2) at Breakup (56 Ma), the lower half of the plume head continued to feed actively upwelling mantle into the proximal portion of the margin; and (3) by 45 Ma, both the remaining plume head and the distal warm layer were exhausted, with excess magmatism thereafter largely confined to a narrow (6 200 km radius) zone immediately above the Iceland plume stem. Alternatively, the warm upper mantle layer that fed excess magmatism in the distal portion of the margin may have been a pre-existing thermal anomaly unrelated to the plume. fl 2001 Elsevier Science B.V. All rights reserved.