Rates of continental breakup magmatism and seafloor spreading in the Norway Basin–Iceland plume interaction

2006 ◽  
Vol 111 (B7) ◽  
Author(s):  
Asbjørn Johan Breivik ◽  
Rolf Mjelde ◽  
Jan Inge Faleide ◽  
Yoshio Murai
Keyword(s):  
Seafloor Spreading ◽  
Continental Breakup ◽  
Iceland Plume

Mobilization of lithospheric mantle carbon during the Palaeocene-Eocene thermal maximum

2021 ◽  
Author(s):  
Thomas Gernon ◽  
Ryan Barr ◽  
John Fitton ◽  
Thea Hincks ◽  
Jack Longman ◽  
...  
Keyword(s):  
North Atlantic ◽  
Lithospheric Mantle ◽  
North Atlantic Ocean ◽  
Continental Breakup ◽  
Ocean Ridges ◽  
The North ◽  
Igneous Provinces ◽  
Thermal Maximum ◽  
Carbon Reservoir ◽  
Iceland Plume

Abstract The early Cenozoic exhibited profound environmental change influenced by plume magmatism, continental breakup, and opening of the North Atlantic Ocean. Global warming culminated in the transient (170 thousand year, kyr) hyperthermal event, the Palaeocene-Eocene thermal maximum (PETM) 56 million years ago (Ma). Although sedimentary methane release has been proposed as a trigger, recent studies have implicated carbon dioxide (CO2) emissions from the coeval North Atlantic igneous province (NAIP). However, we calculate that volcanic outgassing from mid-ocean ridges and large igneous provinces associated with the NAIP yields only one-fifth of the carbon required to trigger the PETM. Rather, we show that volcanic sequences spanning the rift-to-drift phase of the NAIP exhibit a sudden and ∼220-kyr-long intensification of volcanism coincident with the PETM, and driven by substantial melting of the sub-continental lithospheric mantle (SCLM). Critically, the SCLM is enriched in metasomatic carbonates and is a major carbon reservoir. We propose that the coincidence of the Iceland plume and emerging asthenospheric upwelling disrupted the SCLM and caused massive mobilization of this deep carbon. Our melting models and coupled tectonic–geochemical simulations indicate the release of >104 gigatons of carbon, which is sufficient to drive PETM warming. Our model is consistent with anomalous CO2 fluxes during continental breakup, while also reconciling the deficit of deep carbon required to explain the PETM.

U–Pb zircon geochronology of the Ligurian ophiolites (Northern Apennine, Italy): Implications for continental breakup to slow seafloor spreading

2016 ◽  
Vol 666 ◽  
pp. 220-243 ◽  
Author(s):  
Riccardo Tribuzio ◽  
Fabio Garzetti ◽  
Fernando Corfu ◽  
Massimo Tiepolo ◽  
Maria Rosaria Renna
Keyword(s):  
Seafloor Spreading ◽  
Zircon Geochronology ◽  
Continental Breakup

scholarly journals The stratigraphic record of continental breakup, offshore NW Australia

2021 ◽  
Author(s):  
Craig Magee ◽  
Matthew Reeve ◽  
Chris Jackson ◽  
Rebecca Bell ◽  
Ian Bastow
Keyword(s):  
Continental Crust ◽  
Seafloor Spreading ◽  
Magma Intrusion ◽  
Borehole Data ◽  
Continental Breakup ◽  
Rock Record ◽  
Stratigraphic Record ◽  
Surface Marking ◽  
Uplift And Erosion ◽  
Nw Australia

Continental breakup involves a transition from rapid, fault-controlled syn-rift subsidence to relatively slow, post-breakup subsidence induced lithospheric cooling. Yet the stratigraphic record of many rifted margins contain syn-breakup unconformities, indicating episodes of uplift and erosion interrupt this transition. This uplift has been linked to mantle upwelling, depth-dependent extension, and/or isostatic rebound. Deciphering the breakup processes recorded by these unconformities and their related rock record is difficult because associated erosion commonly removes the strata that help constrain the onset and duration of uplift. We examine three major breakup-related unconformities and intervening rock record in the Lower Cretaceous succession of the Gascoyne and Cuvier margins, offshore NW Australia, using seismic reflection and borehole data. These data show the breakup unconformities are disconformable (non-erosive) in places and angular (erosive) in others. Our recalibration of palynomorph ages from rocks underlying and overlying the unconformities shows: (i) the lowermost unconformity developed between 134.98–133.74 Ma (Intra-Valanginian), probably during the localisation of magma intrusion within continental crust and consequent formation of continent-ocean transition zones (COTZ); (2) the middle unconformity formed between ~134–133 Ma (Top Valanginian), possibly coincident with breakup of continental crust and generation of new magmatic (but not oceanic) crust within the COTZs; and (iii) the uppermost unconformity likely developed between ~132.5–131 Ma (i.e. Intra-Hauterivian), coincident with full breakup of continental lithosphere and the onset of seafloor spreading. During unconformity formation, uplift was focused along the continental rift flanks, likely reflecting landward flow of lower crustal and/or lithospheric mantle from beneath areas of localised extension towards the continent (i.e. depth-dependent extension). Our work supports the growing consensus that the ‘breakup unconformity’ is not always a single stratigraphic surface marking the onset of seafloor spreading; multiple unconformities may form and reflect a complex history of uplift and subsidence during the development of continent-ocean transition.

Continental breakup and the onset of ultraslow seafloor spreading off Flemish Cap on the Newfoundland rifted margin

Geology ◽  
2004 ◽  
Vol 32 (1) ◽  
pp. 93 ◽  
Author(s):  
John R. Hopper ◽  
Thomas Funck ◽  
Brian E. Tucholke ◽  
Hans Christian Larsen ◽  
W. Steven Holbrook ◽  
...  
Keyword(s):  
Seafloor Spreading ◽  
Continental Breakup ◽  
Rifted Margin

scholarly journals Opening of the central Atlantic Ocean: Implications for geometric rifting and asymmetric initial seafloor spreading after continental breakup

Tectonics ◽  
2017 ◽  
Vol 36 (6) ◽  
pp. 1129-1150 ◽  
Author(s):  
Y. Biari ◽  
F. Klingelhoefer ◽  
M. Sahabi ◽  
T. Funck ◽  
M. Benabdellouahed ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Seafloor Spreading ◽  
Continental Breakup ◽  
Central Atlantic

Oceanic crustal structures and temporal variations of magmatic budget during seafloor spreading in the East Sub-basin of the South China Sea

2021 ◽  
Vol 436 ◽  
pp. 106475
Author(s):  
Junhui Yu ◽  
Pin Yan ◽  
Yan Qiu ◽  
Matthias Delescluse ◽  
Wenkai Huang ◽  
...  
Keyword(s):  
South China Sea ◽  
South China ◽  
Temporal Variations ◽  
Seafloor Spreading ◽  
The South China Sea ◽  
The South ◽  
China Sea ◽  
Crustal Structures
Sign in / Sign up

Export Citation Format

Share Document