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1. Evaluating the Relationship Between the Area and Latitude of Large Igneous Provinces and Earth's Long-Term Climate State

   https://doi.org/10.31223/OSF.IO/P9NDF  

   Park, Y.; Swanson-Hysell, N.L.; Macdonald, F.M.; Lisiecki, L. (January 2021, Geophysical monograph)

   null (Ed.)

   One of the hypothesized effects of large igneous provinces (LIPs) is planetary cooling on million-year timescales associated with enhanced silicate weathering of freshly emplaced basalt. This study combines reconstructions of the original surface extent and emplacement ages of LIPs, a paleogeographic model, and a parameterization of LIP erosion to estimate LIP area in all latitudinal bands through the Phanerozoic. This analysis reveals no significant correlation between total LIP area, nor LIP area in the tropics, and the extent of continental ice sheets. The largest peaks in tropical LIP area are at times of non-glacial climate. These results suggest that changes in planetary weatherability associated with LIPs are not the fundamental control on whether Earth is in a glacial or non-glacial climate, although they could provide a secondary modulating effect in conjunction with other processes. 

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2. The role of subduction in the formation of Pangaean oceanic large igneous provinces

   https://doi.org/10.1144/SP542-2023-12  

   Heron, Philip_J; Gün, Erkan; Shephard, Grace_E; Dannberg, Juliane; Gassmöller, Rene; Martin, Erin; Sharif, Aisha; Pysklywec, Russell_N; Nance, R_Damian; Murphy, J_Brendan (May 2023, Geological Society, London, Special Publications)

   Abstract Large igneous provinces (LIPs) have been linked to both surface and deep mantle processes. During the formation, tenure and break-up of the supercontinent Pangaea, there is an increase in emplacement events for both continental and oceanic LIPs. There is currently no clear consensus on the origin of LIPs, but a hypothesis relates their formation to crustal emplacement of hot plume material originating in the deep mantle. The interaction of subducted slabs with the lowermost mantle thermal boundary and subsequent return flow is a key control on such plume generation. This mechanism has been explored for LIPs below the interior of a supercontinent (i.e. continental LIPs). However, a number of LIPs formed exterior to Pangaea (e.g. Ontong Java Plateau), with no consensus on their formation mechanism. Here, we consider the dynamics of supercontinent processes as predicted by numerical models of mantle convection and analyse whether circum-supercontinent subduction could generate both interior (continental) and exterior (oceanic) deep mantle plumes. Our numerical models show that subduction related to the supercontinent cycle can reproduce the location and timing of the Ontong Java Plateau, Caribbean LIP and potentially the Shatsky Rise by linking the origin of these LIPs to the return flow that generated deep mantle exterior plumes. 

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3. The Franklin Large Igneous Province and Snowball Earth Initiation

   https://doi.org/10.2138/gselements.19.5.296  

   Macdonald, Francis A; Swanson-Hysell, Nicholas L (October 2023, Elements)

   Large igneous provinces (LIPs) can potentially cause cooling on tens- to thousand-year timescales via injection of sulfur aerosols to the tropo-sphere, and on million-year timescales due to the increase of global weatherability. The ca. 719-Ma Franklin LIP preceded onset of the Sturtian Snowball Earth glaciation by less than two million years, consistent with CO2 drawdown due to weathering of Ca- and Mg-rich LIP basalts, which may have contributed to cooling past a critical runaway ice-albedo threshold. A relatively cool background climate state and Franklin LIP emplacement near a continental margin in the warm wet tropics may have been critical factors for pushing the Earth’s climate past the threshold of runaway glaciation. 

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4. Longest continuously erupting large igneous province driven by plume-ridge interaction

   https://doi.org/10.1130/G47850.1  

   Jiang, Qiang; Jourdan, Fred; Olierook, Hugo K.H.; Merle, Renaud E.; Whittaker, Joanne M. (October 2020, Geology)

   null (Ed.)

   Abstract Large igneous provinces (LIPs) typically form in one short pulse of ∼1–5 Ma or several punctuated ∼1–5 Ma pulses. Here, our 25 new 40Ar/39Ar plateau ages for the main construct of the Kerguelen LIP—the Cretaceous Southern and Central Kerguelen Plateau, Elan Bank, and Broken Ridge—show continuous volcanic activity from ca. 122 to 90 Ma, a long lifespan of >32 Ma. This suggests that the Kerguelen LIP records the longest, continuous high-magma-flux emplacement interval of any LIP. Distinct from both short-lived and multiple-pulsed LIPs, we propose that Kerguelen is a different type of LIP that formed through long-term interactions between a mantle plume and mid-ocean ridge, which is enabled by multiple ridge jumps, slow spreading, and migration of the ridge. Such processes allow the transport of magma products away from the eruption center and result in long-lived, continuous magmatic activity. 

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5. Large Igneous Province Sulfur Emissions Have Long‐Term (>1000 Years) Effects on the Ocean Carbon Cycle

   https://doi.org/10.1029/2024GC011893  

   Cheong, Hee_Jun; Mittal, Tushar; Sprain, Courtney_Jean; Fendley, Isabel_M (March 2025, Geochemistry, Geophysics, Geosystems)

   Abstract Large Igneous Province (LIP) eruptions are thought to have driven environmental and climate change over wide temporal scales ranging from a few to thousands of years. Since the radiative effects and atmospheric lifetime of carbon dioxide (CO₂, warming) and sulfur dioxide (SO₂, cooling) are very different, the conventional assumption has been to analyze the effects of CO₂and SO₂emissions separately and add them together afterward. In this study, we test this assumption by analyzing the joint effect of CO₂and SO₂on the marine carbonate cycle using a biogeochemical carbon cycle box model (Long‐term Ocean‐atmosphere‐Sediment CArbon cycle Reservoir Model). By performing model runs with very fine temporal resolution (∼0.1‐year timestep), we analyze the effects of LIP carbon and sulfur gas emissions on timescales ranging from an individual eruption (hundreds to thousands of years) to the entire long‐term carbon cycle (>100,000 years). We find that, contrary to previous work, sulfur emissions have significant long‐term (>1,000 years) effects on the marine carbon cycle (dissolved inorganic carbon, pH, alkalinity, and carbonate compensation depth). This is due to two processes: the strongly temperature‐dependent equilibrium coefficients for marine carbonate chemistry and the few thousand‐year timescale for ocean overturning circulation. Thus, the effects of volcanic sulfur are not simply additive to the impact of carbon emissions. We develop a causal mechanistic framework to visualize the feedbacks associated with combined carbon and sulfur emissions and the associated timescales. Our results provide a new perspective for understanding the complex feedback mechanisms controlling the environmental effects of large volcanic eruptions over Earth history. 

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