A Triassic large igneous province in the Pontides, northern Turkey: geochemical data for its tectonic setting

The&#160;paleo-position&#160;of&#160;the&#160;North China Craton (NCC) within the Supercontinent Nuna/Columbia is controversial. Hindered by ubiquitous alteration of the very ancient rocks, paleomagnetic studies have not been able yet to conclusively solve this puzzle. Comprehensive analysis&#160;on the relatively limited Precambrian records&#160;is essential&#160;to understand&#160;the geological history of these cratons. Within the NCC, the tectonic setting&#160;of a&#160;~1.78 Ga large igneous province (LIP) is long debated. It is considered to be related to a paleoplume, post-collision extension,&#160;or an Andean continental margin. Knowing its mode of formation constrains the geological evolution of the NCC and its&#160;paleo-position&#160;within the Supercontinent Nuna/Columbia. Here we conduct a study into the anisotropy of magnetic susceptibility&#160;(AMS)&#160;in the dykes and lavas of the ~1.78 Ga LIP, together with systematic rock magnetic experiments, to constrain the geological background&#160;of the igneous event(s), to understand&#160;the tectonic evolution of the NCC, as well as its paleo-position within&#160;the assembly&#160;of the Nuna/Columbia supercontinent.Thirty-three dykes in the northern and middle parts and thirty lavas in the southern part of the NCC were collected. Detailed rock magnetic analyses indicate PSD magnetite to be the dominant magnetic mineral in the samples, occasionally with pyrrhotite in the dykes and hematite in the lavas. The often observed relatively weak anisotropy degree suggests that the AMS ellipsoids probably portray magma flow-related fabrics. The inferred directions from the AMS fabrics of the lavas reveal a radial flow pattern with an eruption center located on the south margin of the NCC. The studied dykes show a predominance of horizontally to subhorizontally northward magma flow, with only few vertical intrusions. These observations imply that the ~1.78 Ga LIP may have formed by magma source(s) at the south margin of the NCC. Some localized magma sub-chambers may have formed during the propagation of the magma and could have been responsible for the less common vertically intruded dykes and the EW-trending dykes. Therefore, we favor a plume-related tectonic setting for the ~1.78 Ga LIP with the eruption center along the margin of the NCC. It can serve as an essential criterion to search for possible neighbour(s) of the NCC within Nuna/Columbia, which should preserve the relics of the ~1.78 Ga LIP. Our study, in combination with extant geological and paleomagnetic results suggests a close linkage of the NCC with the S&#227;o Francisco-Congo, Rio de la Plata and Siberia cratons in the Nuna/Columbia supercontinent.

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An early Paleozoic silicic large igneous province in NE Gondwana: a preliminary synthesis

10.5194/egusphere-egu2020-8193 ◽

2020 ◽

Cited By ~ 1

Author(s):

Wei Dan ◽

J. Brendan Murphy ◽

Gong-Jian Tang ◽

Xiu-Zheng Zhang ◽

Qiang Wang

Keyword(s):

Tectonic Setting ◽

Oceanic Lithosphere ◽

Large Igneous Province ◽

Early Paleozoic ◽

Magmatic Rocks ◽

Igneous Province ◽

Granitoid Rocks ◽

Andean Type ◽

Almost All ◽

The Relationship

Five major oceans (Iapetus, Rheic, Proto-Tethys, Paleo-Tethys and Paleo-Asian) formed during or after assembly of the Gondwana continent. However, the relationship between them is poorly understood, largely due to the complex and disputed evolution of NE Gondwana in the early Paleozoic. Here we present a summary of early Paleozoic tectono-thermal events in the NE Gondwana and discuss their tectonic settings. Early Paleozoic magmatic rocks are widely distributed in the Himalaya, Lhasa, Southern Qiangtang, Baoshan, Sibumasu and Tengchong terranes, and their ages were loosely constrained to be ca. 530-430 Ma. However, after a critical review of these dating results, we propose the magmatic rocks were mostly formed between ca. 500-460 Ma. Although bimodal, they are dominated by granitoid rocks distributed over an area of >2500 km &#215; 900 km. Thus, they constitute a typical silicic large igneous province. Almost all granitoid rocks were derived from partial melting of sedimentary rocks, but a few show A-type characteristics. Coeval amphibolite-facies metamorphic rocks yield ages of 490-465 Ma. A sedimentary hiatus marked by either a disconformity or angular unconformity coeval with the major magmatic flare-up period is evident in all terranes. Thus, present evidence doesn&#8217;t favor either the conventional Andean-type subduction model, in which these magmatic rocks reflect subduction of Proto-Tethys oceanic lithosphere beneath the northern Gondwanan margin, or a post-collision setting, in which extension is associated with the collapse of the Pan-African orogeny in NE Gondwana. The tectonic setting for this magmatic province is tentatively related to a plume in a far-field subduction zone.

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Peridotites and basaltic rocks within an ophiolitic mélange from the SW igneous province of Puerto Rico: relation to the evolution of the Caribbean Plate

Geological Magazine ◽

10.1017/s001675681500093x ◽

2016 ◽

Vol 154 (1) ◽

pp. 96-118

Author(s):

NADJA OMARA CINTRON FRANQUI ◽

SUNG HI CHOI ◽

DER-CHUEN LEE

Keyword(s):

Puerto Rico ◽

Tectonic Setting ◽

Geochemical Data ◽

Transform Fault ◽

Caribbean Plate ◽

Basaltic Rocks ◽

The North ◽

Ophiolitic Mélange ◽

Igneous Province ◽

The Caribbean

AbstractThe geology of Puerto Rico is divided into three regions: the north, central and SW igneous provinces. Characterized by its Jurassic ophiolitic mélange basement, lithology of the SW Igneous Province (SIP) is not related to either of the other two provinces. The ophiolitic mélange is exposed in three peridotite belts: Monte del Estado, Rio Guanajibo and Sierra Bermeja. We present geochemical data to identify the tectonic setting of the SIP peridotite formation and its relation to the evolution of the Caribbean Plate. Comparisons of spinel Cr no. (13–21), Mg no. (63.3–69.6) and TiO2suggest an abyssal peridotite origin; however, only Sierra Bermeja presents high TiO2characteristics of a mid-ocean-ridge-basalt- (MORB-) like melt reaction. Temperatures determined with two-pyroxene geothermometers indicated a cold thermal regime ofc. 800–1050°C, with characteristics of large-offset transform fault abyssal peridotites. The geochemistry and Sr–Nd–Hf–Pb isotopic compositions of basalts within the mélange were also analysed. Las Palmas amphibolites exhibited normal-MORB-like rare earth element (REE) and trace-element patterns, whereas metabasalts and Lower Cajul basalts exhibited island-arc tholeiitic-like patterns. Highly radiogenic Sr isotopes (0.70339–0.70562) of the basalts suggest seawater alteration; however, Pb–Pb and Nd–Hf isotope correlations represent the primary compositions of a Pacific/Atlantic MORB source for the amphibolites, metabasalts and Lower Cajul basalts. We propose that the SIP ophiolitic mélange was formed along a large-offset transform fault, which initiated subduction and preserved both proto-Pacific and proto-Caribbean lithospheric mantle. Younger Upper Cajul basalts exhibited enriched-MORB-like geochemical and isotopic signatures, which can be attributed to a tectonized Caribbean ocean plateau.

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Mineralogical and Geochemical Constraints on Magma Evolution and Late-Stage Crystallization History of the Breivikbotn Silicocarbonatite, Seiland Igneous Province in Northern Norway: Prerequisites for Zeolite Deposits in Carbonatite Complexes

Minerals ◽

10.3390/min8110537 ◽

2018 ◽

Vol 8 (11) ◽

pp. 537 ◽

Cited By ~ 2

Author(s):

Dmitry Zozulya ◽

Kåre Kullerud ◽

Erling Ravna ◽

Yevgeny Savchenko ◽

Ekaterina Selivanova ◽

...

Keyword(s):

Trace Element ◽

Tectonic Setting ◽

Spatial Proximity ◽

Geochemical Data ◽

Chemical Compositions ◽

Igneous Province ◽

Magmatic Stage ◽

Stage Crystallization ◽

History Of ◽

Late Magmatic Stage

The present work reports on new mineralogical and whole-rock geochemical data from the Breivikbotn silicocarbonatite (Seiland igneous province, North Norway), allowing conclusions to be drawn concerning its origin and the role of late fluid alteration. The rock shows a rare mineral association: calcite + pyroxene + amphibole + zeolite group minerals + garnet + titanite, with apatite, allanite, magnetite and zircon as minor and accessory minerals, and it is classified as silicocarbonatite. Calcite, titanite and pyroxene (Di36–46 Acm22–37 Hd14–21) are primarily magmatic minerals. Amphibole of mainly hastingsitic composition has formed after pyroxene at a late-magmatic stage. Zeolite group minerals (natrolite, gonnardite, Sr-rich thomsonite-(Ca)) were formed during hydrothermal alteration of primary nepheline by fluids/solutions with high Si-Al-Ca activities. Poikilitic garnet (Ti-bearing andradite) has inclusions of all primary minerals, amphibole and zeolites, and presumably crystallized metasomatically during a late metamorphic event (Caledonian orogeny). Whole-rock chemical compositions of the silicocarbonatite differs from the global average of calciocarbonatites by elevated silica, aluminium, sodium and iron, but show comparable contents of trace elements (REE, Sr, Ba). Trace element distributions and abundances indicate within-plate tectonic setting of the carbonatite. The spatial proximity of carbonatite and alkaline ultramafic rock (melteigite), the presence of “primary nepheline” in carbonatite together with the trace element distributions indicate that the carbonatite was derived by crystal fractionation of a parental carbonated foidite magma. The main prerequisites for the extensive formation of zeolite group minerals in silicocarbonatite are revealed.

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Collision of the Caribbean Large Igneous Province with the Americas: Earliest evidence from the forearc of Costa Rica

Geological Society of America Bulletin ◽

10.1130/b35037.1 ◽

2019 ◽

Vol 131 (9-10) ◽

pp. 1555-1580 ◽

Cited By ~ 6

Author(s):

Goran Andjić ◽

Peter O. Baumgartner ◽

Claudia Baumgartner-Mora

Keyword(s):

Costa Rica ◽

North America ◽

Large Igneous Province ◽

Geochemical Data ◽

Published Data ◽

Valuable Insight ◽

Oceanic Plateau ◽

The Pacific ◽

Igneous Province ◽

The Caribbean

AbstractThe Cretaceous period was marked by the most voluminous episodes of oceanic plateau volcanism in the Phanerozoic Eon. Primarily affecting the Pacific, mantle plumes generated oceanic plateaus during three main phases (ca. 145–140 Ma, ca. 122–115 Ma, and ca. 100–90 Ma). Central America is one of the very few circum-Pacific margins where remnants of these Cretaceous plateaus were accreted. The study of their onland exposures provides a highly valuable insight into the complexity and diversity of oceanic plateau histories, from their eruption to their accretion. Exposed in northern Costa Rica, the plateau remnants of the Nicoya Peninsula originated from a Jurassic oceanic crust over-thickened by Early and Late Cretaceous hotspots. These sheared-off pieces of the Farallon Plate testify to the early tectonic interaction of the Caribbean Large Igneous Province (CLIP, ca. 94–89 Ma) with North America, initiated <5 m.y. after the onset of CLIP eruption. By combining our results with previously published data, we propose an updated tectono-stratigraphic framework that divides the Nicoya Peninsula into two oceanic plateau terranes. (1) The accretion timing of the Aptian to Turonian Manzanillo Terrane is constrained by the Coniacian (ca. 89–86 Ma) base of the overlapping Loma Chumico Formation. The proximal tuffaceous forearc deposits of the Loma Chumico Formation are the oldest evidence of a volcanic arc in Costa Rica—called here the Berrugate Arc—as revealed by new biostratigraphic and geochemical data. (2) The Nicoya Complex s. str. is a composite plateau remnant containing rocks of Bajocian to earliest Campanian age. Its accretion occurred during the middle Campanian (ca. 79–76 Ma) and shut down the Berrugate Arc. In contrast to the collision of CLIP with North America, onset of the collision of CLIP with South America began much later, during the latest Campanian (ca. 75–73 Ma).

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Mineralogical and Geochemical Constraints on the Origin and Late-Stage Crystallization History of the Breivikbotn Silicocarbonatite, Seiland Igneous Province in Northern Norway: Prerequisites for Zeolite Deposits in Carbonatite Complexes

10.20944/preprints201809.0551.v1 ◽

2018 ◽

Author(s):

Dmitry Zozulya ◽

Kåre Kullerud ◽

Erling Ravna ◽

Yevgeny Savchenko ◽

Ekaterina Selivanova ◽

...

Keyword(s):

Trace Element ◽

Tectonic Setting ◽

Spatial Proximity ◽

Geochemical Data ◽

Chemical Compositions ◽

Igneous Province ◽

Magmatic Stage ◽

Stage Crystallization ◽

History Of ◽

Late Magmatic Stage

The present work reports new mineralogical and whole rock geochemical data from the Breivikbotn silicocarbonatite (Seiland igneous province, North Norway), allowing conclusions to be drawn concerning its origin and the role of late fluid alteration. The rock shows a rare mineral association: calcite + pyroxene + amphibole + zeolite group minerals + garnet + titanite, with apatite, allanite, magnetite and zircon as minor and accessory minerals, and it is classified as silicocarbonatite. Calcite, titanite and pyroxene (Di36-46 Acm22-37 Hd14-21) are primarily magmatic minerals. Amphibole of hastingsitic composition has formed after pyroxene at a late-magmatic stage. Zeolite group minerals (natrolite, gonnardite, Sr-rich thomsonite-(Ca)) were formed during hydrothermal alteration of primary nepheline by fluids/solutions with high Si-Al-Ca activities. Poikilitic garnet (Ti-bearing andradite) has inclusions of all primary minerals, amphibole and zeolites, and presumably crystallized metasomatically during a late metamorphic event (Caledonian orogeny). Whole rock chemical compositions of the silicocarbonatite differs from the global average of calciocarbonatites by elevated silica, aluminium, sodium and iron, but show comparable contents of trace elements (REE, Sr, Ba). Trace element distributions indicate within-plate tectonic setting of the carbonatite. The spatial proximity of carbonatite and alkaline ultramafic rock (melteigite), the presence of “primary nepheline” in carbonatite together with the trace element distributions indicate that the carbonatite was derived from crystal fractionation of a parental carbonated foidite magma. The main prerequisites for the extensive formation of zeolite group minerals in silicocarbonatite are revealed.

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Global Implication of Mesoproterozoic (1.4 Ga) Magmatism Within Sette-Daban Range (Southeast Siberia)

10.21203/rs.3.rs-396668/v1 ◽

2021 ◽

Author(s):

Sergey Malyshev ◽

Alexey Ivanov ◽

Andrey Khudoley ◽

Vadim Kamenetsky ◽

Maya Kamenetsky ◽

...

Keyword(s):

Siberian Craton ◽

Direct Consequence ◽

Large Igneous Province ◽

Tectonic Activity ◽

Geochemical Data ◽

Trace Element Pattern ◽

Tectonic Events ◽

Element Pattern ◽

Igneous Province ◽

Break Up

Abstract Mesoproterozoic period included several global tectonic events like break-up of Nuna and formation of Rodinia. However, although Siberia is a significant piece of both supercontinents, Mesoproterozoic time is marked by quiescence of magmatic and tectonic activity in it. We report here a mafic dyke (named Gornostakh dyke) in the southeastern Siberian Craton dated at 1419 ± 32 Ma by LA-ICPMS U-Pb geochronology of apatite. Paleogeographic reconstructions suggest that Siberia was connected to Laurentia and Baltica and their reconfiguration interrupts a prolonged tectonic quiescence in the Siberian Craton from ca. 1.88 Ga reflecting a transition from Nuna to Rodinia configuration. The 1419 Ma Gornostakh dyke and coeval deformation observed in the structure of the region may be a direct consequence of this transition. The dyke has tholeiitic compositions with high MgO and alkaline content, low-Ti, and arc-like trace element pattern. Due to the absence of subduction tectonics in the study area, geochemical data could be attributed to a significant contribution from metasomatically enriched subcontinental lithospheric mantle previously modified by subduction processes. Such mafic magmatism on the margin of the Siberian Craton could be related to a hypothetic large igneous province, which initiated the continental break-up.

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Magma Plumbing System of Emeishan Large Igneous Province at the End-Permian: Insights from Clinopyroxene Compositional Zoning and Thermobarometry

Minerals ◽

10.3390/min10110979 ◽

2020 ◽

Vol 10 (11) ◽

pp. 979

Author(s):

Jun-Hao Hu ◽

Jing-Wen Liu ◽

Tao Song ◽

Bai-Shun Shi

Keyword(s):

Tectonic Setting ◽

Large Igneous Province ◽

Magma Ascent ◽

Magma Chambers ◽

Flood Basalts ◽

Compositional Zoning ◽

Magma Plumbing System ◽

Emeishan Large Igneous Province ◽

Mafic Intrusions ◽

Igneous Province

The end-Permian Emeishan Large Igneous Province (ELIP) in SW China is widely accepted to have formed by mantle plume activities, forming voluminous flood basalts and rare picrites. Although many studies were performed on the petrogenesis and tectonic setting, the detailed conditions and processes within the magma chamber(s) remain unsolved. In this study, we studied the sector-/oscillatory-zoned clinopyroxene (Cpx) phenocrysts and performed Cpx-liquid thermobarometric calculation to constrain the physicochemical processes within the magma chambers. The results show that Cpx phenocrysts from the high-Mg basalts were crystallized at 4–27 (average 17) km, whilst those from the low-Mg basalt were crystallized at 0–23 (average 9) km depth. The sector and oscillatory Cpx zoning in the high-Mg basalts show that the magma had experienced undercooling and multistage recharge events in the deep-staging chamber(s). The magma replenishments may have eventually led to the eruption of high-Mg basalts, and magma ascent to the upper crust for further fractionation to form the low-Mg basalts and mafic intrusions.

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