The links between large igneous provinces, continental break-up and environmental change: evidence reviewed from Antarctica

ABSTRACTEarth history is punctuated by events during which large volumes of predominantly mafic magmas were generated and emplaced by processes that are generally accepted as being, unrelated to ‘normal’ sea-floor spreading and subduction processes. These events form large igneous provinces (LIPs) which are best preserved in the Mesozoic and Cenozoic where they occur as continental and ocean basin flood basalts, giant radiating dyke swarms, volcanic rifted margins, oceanic plateaus, submarine ridges, and seamount chains. The Mesozoic history of Antarctica is no exception in that a number of different igneous provinces were emplaced during the initial break-up and continued disintegration of Gondwana, leading to the isolation of Antarctica in a polar position. The link between the emplacement of the igneous rocks and continental break-up processes remains controversial. The environmental impact of large igneous province formation on the Earth System is equally debated. Large igneous province eruptions are coeval with, and may drive environmental and climatic effects including global warming, oceanic anoxia and/or increased oceanic fertilisation, calcification crises, mass extinction and release of gas hydrates.This review explores the links between the emplacement of large igneous provinces in Antarctica, the isolation of Antarctica from other Gondwana continents, and possibly related environmental and climatic changes during the Mesozoic and Cenozoic.

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Refining the temporal relation between Large Igneous Provinces and carbon cycle perturbations: not every LIP triggers environmental crises, not every crisis is due to a LIP!

10.5194/egusphere-egu2020-2141 ◽

2020 ◽

Author(s):

Urs Schaltegger ◽

Philipp Widmann ◽

Nicolas D. Greber ◽

Luis Lena ◽

Sean P. Gaynor ◽

...

Keyword(s):

Carbon Cycle ◽

Volcanic Activity ◽

Planetary Science ◽

Large Igneous Province ◽

Early Triassic ◽

Magmatic Activity ◽

Triassic Boundary ◽

Large Igneous Provinces ◽

Igneous Provinces ◽

Igneous Province

The connection between volcanic activity of large igneous provinces and the respective feedback from environment and biosphere contributing to the carbon cycle has been investigated at the present temporal resolution of high-precision U/Pb dating. Uncertainties of 0.05 % on the 206Pb/238U age from zircon dating allow a resolution of 30-50 ka pulses of magmatic activity; simultaneously, the duration of carbon isotope excursions (CIE) can be determined, the geological boundaries dated, or global sedimentary gaps can be quantified at the same level of precision. This contribution demonstrates with two case studies that we can refine the contemporaneity and start to reliably infer causality of consecutive events at the 104 year level.Until the Anisian the aftermath of the Permo-Triassic Boundary Mass extinction (PTBME; ~251.94 Ma, Baresel et al., 2017) is characterized by profound fluctuations of the global carbon cycle with amplitudes of up to 8 &#8240; in d13Ccarb values. These represent large variations in the global climate and biological crises, in particular during the end-Smithian extinction event (~249.1 Ma). A precise chronology from the southern Nanpanjiang basin (China) allows for a quantification of these fluctuations of Earth climate. Following the volcanic pulse causing the PTBME, several discontinuous episodes of volcanism of the Siberian Large Igneous Province (S-LIP) were generally assumed to have caused the subsequent Early Triassic carbon cycle fluctuations. This is, however, in disagreement with the geochronological database of precise zircon U/Pb dates that put an end to the volcanic activity at 250.6 Ma (Burgess & Bowring, 2015; Augland et al., 2019). Therefore, recurrent S-LIP volcanism is an unlikely explanation for the Early Triassic unstable carbon cycle.The initial intrusive pulse of the Karoo Large Igneous Province (K-LIP) formed the sill/dyke complex of the Karoo basin, South Africa. New, precise U/Pb geochronology confirms its very short duration at around 183.2-182.8 Ma (Burgess et al., 2015; Corfu et al., 2016), as well as its synchronicity with the lower Toarcian oceanic anoxic event (T-OAE), and a carbon cycle disturbance of presumable global importance. Repeated excursions in d13Corg of up to 3 &#8240; in the late Pliensbachian (~185.5 Ma) as well as at the Pliensbachian-Toarcian boundary (~183.5 Ma) are therefore at least partly older than any known magmatic activity of the K-LIP (Lena et al., 2019). We therefore, again, must invoke non-volcanic drivers in order to explain the instability of the carbon cycle.These two case histories demonstrate that in order to invoke causality and global importance to carbon cycle instability, as well as for the testing of its correlation with volcanic episodes, we need to rely on geochronology of both sedimentary and volcanic records at the 104 years level of precision.References: Augland et al. (2019) Scientific Reports, 9:18723&#160;; Baresel et al. (2017) Solid Earth, 8, 361&#8211;378, 2017; Burgess & Bowring (2015) Science Advances, 1(7), e1500470&#8211;e1500470; Burgess et al. (2015) Earth and Planetary Science Letters, 415(C), 90&#8211;99; Corfu, F. et al. (2016) Earth and Planetary Science Letters, 434(C), 349&#8211;352; Lena et al. (2019) Scientific Reports, 9:18430.

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The origins of high-Ti and low-Ti magmas in large igneous provinces, insights from melt inclusion trace elements and Sr-Pb isotopes in the Emeishan large Igneous Province

Lithos ◽

10.1016/j.lithos.2019.06.014 ◽

2019 ◽

Vol 344-345 ◽

pp. 122-133 ◽

Cited By ~ 6

Author(s):

Le Zhang ◽

Zhong-Yuan Ren ◽

Monica R. Handler ◽

Ya-Dong Wu ◽

Lei Zhang ◽

...

Keyword(s):

Trace Elements ◽

Melt Inclusion ◽

Pb Isotopes ◽

Large Igneous Province ◽

Large Igneous Provinces ◽

Emeishan Large Igneous Province ◽

Igneous Provinces ◽

Igneous Province

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An evaluation of Deccan Traps eruption rates using geochronologic data

Geochronology ◽

10.5194/gchron-3-181-2021 ◽

2021 ◽

Vol 3 (1) ◽

pp. 181-198

Author(s):

Blair Schoene ◽

Michael P. Eddy ◽

C. Brenhin Keller ◽

Kyle M. Samperton

Keyword(s):

Deccan Traps ◽

Large Igneous Province ◽

Systematic Uncertainties ◽

Igneous Provinces ◽

Dating Methods ◽

Igneous Province ◽

Before And After ◽

History Of ◽

Earth’S Climate ◽

Chicxulub Impact

Abstract. Recent attempts to establish the eruptive history of the Deccan Traps large igneous province have used both U−Pb (Schoene et al., 2019) and 40Ar/39Ar (Sprain et al., 2019) geochronology. Both of these studies report dates with high precision and unprecedented coverage for a large igneous province and agree that the main phase of eruptions began near the C30n–C29r magnetic reversal and waned shortly after the C29r–C29n reversal, totaling ∼ 700–800 kyr duration. These datasets can be analyzed in finer detail to determine eruption rates, which are critical for connecting volcanism, associated volatile emissions, and any potential effects on the Earth's climate before and after the Cretaceous–Paleogene boundary (KPB). It is our observation that the community has frequently misinterpreted how the eruption rates derived from these two datasets vary across the KPB. The U−Pb dataset of Schoene et al. (2019) was interpreted by those authors to indicate four major eruptive pulses before and after the KPB. The 40Ar/39Ar dataset did not identify such pulses and has been largely interpreted by the community to indicate an increase in eruption rates coincident with the Chicxulub impact (Renne et al., 2015; Richards et al., 2015). Although the overall agreement in eruption duration is an achievement for geochronology, it is important to clarify the limitations in comparing the two datasets and to highlight paths toward achieving higher-resolution eruption models for the Deccan Traps and for other large igneous provinces. Here, we generate chronostratigraphic models for both datasets using the same statistical techniques and show that the two datasets agree very well. More specifically, we infer that (1) age modeling of the 40Ar/39Ar dataset results in constant eruption rates with relatively large uncertainties through the duration of the Deccan Traps eruptions and provides no support for (or evidence against) the pulses identified by the U−Pb data, (2) the stratigraphic positions of the Chicxulub impact using the 40Ar/39Ar and U−Pb datasets do not agree within their uncertainties, and (3) neither dataset supports the notion of an increase in eruption rate as a result of the Chicxulub impact. We then discuss the importance of systematic uncertainties between the dating methods that challenge direct comparisons between them, and we highlight the geologic uncertainties, such as regional stratigraphic correlations, that need to be tested to ensure the accuracy of eruption models. While the production of precise and accurate geochronologic data is of course essential to studies of Earth history, our analysis underscores that the accuracy of a final result is also critically dependent on how such data are interpreted and presented to the broader community of geoscientists.

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Existence of the DHArwar-BAstar-SInghbhum (DHABASI) megacraton since 3.35 Ga: Constraints from the Precambrian Large Igneous Province record

Geological Society London Special Publications ◽

10.1144/sp518-2021-53 ◽

2021 ◽

pp. SP518-2021-53

Author(s):

Rajesh K. Srivastava ◽

Richard E. Ernst ◽

Ulf Söderlund ◽

Amiya K. Samal ◽

Om Prakash Pandey ◽

...

Keyword(s):

Building Block ◽

Large Igneous Province ◽

Indian Shield ◽

Large Igneous Provinces ◽

The Past ◽

Igneous Provinces ◽

Igneous Province ◽

The Individual ◽

Age Range

AbstractWe propose a Precambrian megacraton (consisting of two or more ancient cratons) ‘DHABASI’ in the Indian Shield that includes the Dharwar, Bastar and Singhbhum cratons. This interpretation is mainly based on seven large igneous provinces (LIPs) that are identified in these three cratons over the age range of ca. 3.35-1.77 Ga, a period of at least 1.6 Gyr. The absence of any subsequent breakup of ‘DHABASI’ since 1.77 Ga suggests that this megacraton has existed for the past 3.35 Gyr.In addition to their use in recognizing this megacraton, these LIP events may also provide likely targets for Cu-Ni-Cr-Co-PGE deposits. We suggest that the megacraton ‘DHABASI’ was an integral part of supercontinents/supercratons through Earth's history, and that it should be utilized as a distinct building block for paleocontinental reconstructions rather than using the individual Dharwar, Bastar and Singhbhum cratons.

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Geochemistry and U-Pb Geochronology of the 1450-1425 Ma Large Igneous Province of Eastern Laurentia and 2480-780 Ma Large Igneous Provinces of Western Laurentia

10.22215/etd/2017-12067 ◽

2017 ◽

Author(s):

Christopher Rogers

Keyword(s):

Large Igneous Province ◽

Large Igneous Provinces ◽

Igneous Provinces ◽

Igneous Province

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The Tethyan Himalaya igneous province: Early melting products of the Kerguelen mantle plume

Journal of Petrology ◽

10.1093/petrology/egab069 ◽

2021 ◽

Author(s):

Sheng-Sheng Chen ◽

Wei-Ming Fan ◽

Ren-Deng Shi ◽

Ji-Feng Xu ◽

Yong-Min Liu

Keyword(s):

Mantle Plume ◽

Crustal Contamination ◽

Large Igneous Province ◽

Mafic Rocks ◽

Os Isotopes ◽

Igneous Province ◽

Break Up ◽

Low Degrees ◽

The Relationship ◽

Tethyan Himalaya

Abstract The Kerguelen large igneous province (LIP) has been related to mantle plume activity since at least 120 Ma. There are some older (147–130 Ma) magmatic provinces on circum-eastern Gondwana, but the relationship between these provinces and the Kerguelen mantle plume remains controversial. Here we present petrological, geochronological, geochemical, and Sr–Nd–Hf–Pb–Os isotopic data for high-Ti mafic rocks from two localities (Cuona and Jiangzi) in the eastern Tethyan Himalaya igneous province (147–130 Ma). Zircon grains from these two localities yielded concordant weighted mean 206Pb/238U ages of 137.25 ± 0.98 and 131.28 ± 0.78 Ma (2σ), respectively. The analyzed mafic rocks are enriched in high field strength elements and have positive Nb–Ta anomalies relative to Th and La, which have ocean island basalt-like characteristics. The Cuona basalts were generated by low degrees of melting (3–5%) of garnet lherzolites (3–5 vol.% garnet), and elsewhere the Jiangzi diabases were formed by relatively lower degrees of melting (1–3%) of garnet lherzolite (1–5 vol.% garnet). The highly radiogenic Os and Pb isotopic compositions of the Jiangzi diabases were produced by crustal contamination, but the Cuona basalts experienced the least crustal contamination given their relatively low γOs(t), 206Pb/204Pbi, 207Pb/204Pbi, and 208Pb/204Pbi values. Major and trace element geochemical and Sr–Nd–Hf–Pb–Os isotope data for the Cuona basalts are similar to products of the Kerguelen mantle plume head. Together with high mantle potential temperatures (>1500°C), this suggests that the eastern Tethyan Himalaya igneous province (147–130 Ma) was an early magmatic product of the Kerguelen plume. A mantle plume initiation model can explain the temporal and spatial evolution of the Kerguelen LIP, and pre-continental break-up played a role in the breakup of eastern Gondwana, given the >10 Myr between initial mantle plume activity (147–130 Ma) and continental break-up (132–130 Ma). Like studies of Re-Os isotopes in other LIPs, the increasing amount of crustal assimilation with distance from the plume stem can explain the variations in radiogenic Os.

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Introduction: from the British Tertiary into the future – modern perspectives on the British Palaeogene and North Atlantic Igneous provinces

Geological Magazine ◽

10.1017/s001675680900627x ◽

2009 ◽

Vol 146 (3) ◽

pp. 305-308 ◽

Cited By ~ 3

Author(s):

DOUGAL A. JERRAM ◽

KATHRYN M. GOODENOUGH ◽

VALENTIN R. TROLL

Keyword(s):

North Atlantic ◽

18Th Century ◽

North Atlantic Ocean ◽

Volcanic Rocks ◽

Large Igneous Province ◽

The North ◽

Igneous Provinces ◽

Starting Point ◽

Igneous Province ◽

Dyke Swarms

The study of volcanic rocks and igneous centres has long been a classic part of geological research. Despite the lack of active volcanism, the British Isles have been a key centre for the study of igneous rocks ever since ancient lava flows and excavated igneous centres were recognized there in the 18th century (Hutton, 1788). This led to some of the earliest detailed studies of petrology. The starting point for many of these studies was the British Palaeogene Igneous Province (BPIP; formerly known as the ‘British Tertiary’ (Judd, 1889), and still recognized by this name by many geologists around the globe). This collection of lavas, volcanic centres and sill/dyke swarms covers much of the west of Scotland and the Antrim plateau of Northern Ireland, and together with similar rocks in the Faroe Islands, Iceland and Greenland forms a world-class Large Igneous Province. This North Atlantic Igneous Province (NAIP) began to form through continental rifting above a mantle plume at c. 60 Ma, and subsequently evolved as North America separated from Europe, creating the North Atlantic Ocean.

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Nature of Cretaceous dolerite dikes with two distinct trends in the Damodar Valley, eastern India: Constraints on their linkage to mantle plumes and large igneous provinces from 40Ar/39Ar geochronology and geochemistry

Lithosphere ◽

10.1130/l1108.1 ◽

2019 ◽

Vol 12 (1) ◽

pp. 40-52 ◽

Cited By ~ 1

Author(s):

Rajesh K. Srivastava ◽

Fei Wang ◽

Wenbei Shi ◽

Anup K. Sinha ◽

Kenneth L. Buchan

Keyword(s):

Sedimentary Basins ◽

Geochemical Characteristics ◽

Large Igneous Province ◽

Mantle Plumes ◽

Eastern India ◽

Group I ◽

Igneous Provinces ◽

Damodar Valley ◽

Igneous Province ◽

Reunion Plume

Abstract Two distinct sets of Cretaceous dolerite dikes intrude the Chhotanagpur gneissic complex of eastern India, mostly within the Damodar Valley Gondwanan sedimentary basins. One dike set trends NNE to ENE, whereas the other set, which includes the prominent Salma dike, trends NW to NNW. One dike from each set in the Raniganj Basin was dated using the 40Ar/39Ar method in order to resolve a controversy concerning the emplacement age of the Salma dike. The NE-trending dike yielded a plateau age of 70.5 ± 0.9 Ma, whereas the NNW-trending Salma dike is much older, with a plateau age of 116.0 ± 1.4 Ma. These results demonstrate that the Salma dike was emplaced at ca. 116 Ma and not at ca. 65 Ma, as suggested in an earlier study. Geochemical characteristics of the two dikes are also distinct and indicate that they belong to previously identified high-Ti and low-Ti dolerite groups, respectively. The observed geochemical characteristics of both dike sets are comparable with the geochemistry of basalts of the Kerguelen Plateau, Bunbury Island, and Rajmahal Group I and suggest a connection to mantle plumes. The new age data presented herein indicate that these two magmatic episodes in the eastern Indian Shield were related to the ca. 120–100 Ma Kerguelen mantle plume and its associated Greater Kerguelen large igneous province and the ca. 70–65 Ma Réunion plume and its associated Deccan large igneous province, respectively.

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