Basic volcanism contemporaneous with the Sturtian glacial episode in NE Scotland

ABSTRACTThe Dalradian Supergroup contains three distinct glacigenic units, formerly termed ‘Boulder Beds’, which are correlated with widespread Neoproterozoic glaciations. The oldest and thickest unit, the Port Askaig Formation, marks the Appin–Argyll group boundary of the Dalradian Supergroup and has been correlated with the Middle Cryogenian (Sturtian) glaciation. The Auchnahyle Formation, a diamictite-bearing sequence near Tomintoul in NE Scotland, exhibits strong lithological similarities to the Port Askaig Formation. Both these glacigenic ‘Boulder Bed’ units contain abundant dolomite clasts in their lower parts and more granitic material at higher levels. Both metadiamictite units are overlain by thick shallow-marine quartzite units. C isotope data from Appin Group carbonate strata below the Auchnahyle Formation support this correlation. U–Pb laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) detrital zircon data from the Auchnahyle Formation metadiamictite differ slightly from the Port Askaig Formation, but are similar to detrital zircon spectra obtained from the Macduff Formation, a diamictite unit in the younger Southern Highland Group of the Dalradian Supergroup; both apparently reflect derivation from local basement rocks. No detritus younger than 0·9 Ga is observed, so the data do not constrain significantly the depositional age of the glacial strata. A thin tholeiitic pillow basalt unit in the lower part of the Auchnahyle Formation is geochemically distinct from pre-tectonic metadolerite sills and from basic metavolcanic rocks up-section. A Sturtian (c. 720–700 Ma) age for the Auchnahyle Formation metadiamictite would imply that this basaltic volcanism represents the oldest recorded volcanic activity in the Dalradian Supergroup and is inferred to represent an early, local phase of proto-Iapetan rifting within the Rodinian supercontinent.

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Supplemental Material: Recalibrating Rodinian rifting in the northwestern United States

10.1130/geol.s.13530668.v1 ◽

2021 ◽

Author(s):

Daniel Brennan ◽

et al.

Keyword(s):

United States ◽

Mass Spectrometry ◽

Detrital Zircon ◽

Inductively Coupled Plasma ◽

Individual Sample ◽

Inductively Coupled ◽

Icp Ms ◽

Plasma Mass Spectrometry ◽

Depositional Age ◽

Conventional Laser

Individual sample detrital zircon results, alternative maximum depositional age calculations, conventional laser-ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) methodology, rapid LA-ICP-MS methodology, sample locations, and detrital zircon U-Pb/Lu-Hf results for all analyses and compiled U-Pb data.<br>

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Supplemental Material: Recalibrating Rodinian rifting in the northwestern United States

10.1130/geol.s.13530668.v3 ◽

2021 ◽

Author(s):

Daniel Brennan ◽

et al.

Keyword(s):

United States ◽

Mass Spectrometry ◽

Detrital Zircon ◽

Inductively Coupled Plasma ◽

Individual Sample ◽

Inductively Coupled ◽

Icp Ms ◽

Plasma Mass Spectrometry ◽

Depositional Age ◽

Conventional Laser

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Supplemental Material: Recalibrating Rodinian rifting in the northwestern United States

10.1130/geol.s.13530668.v2 ◽

2021 ◽

Author(s):

Daniel Brennan ◽

et al.

Keyword(s):

United States ◽

Mass Spectrometry ◽

Detrital Zircon ◽

Inductively Coupled Plasma ◽

Individual Sample ◽

Inductively Coupled ◽

Icp Ms ◽

Plasma Mass Spectrometry ◽

Depositional Age ◽

Conventional Laser

Download Full-text

Supplemental Material: Recalibrating Rodinian rifting in the northwestern United States

10.1130/geol.s.13530668 ◽

2021 ◽

Author(s):

Daniel Brennan ◽

et al.

Keyword(s):

United States ◽

Mass Spectrometry ◽

Detrital Zircon ◽

Inductively Coupled Plasma ◽

Individual Sample ◽

Inductively Coupled ◽

Icp Ms ◽

Plasma Mass Spectrometry ◽

Depositional Age ◽

Conventional Laser

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U–Pb age and Lu–Hf signatures of detrital zircon from Palaeozoic sandstones in the Oslo Rift, Norway

Geological Magazine ◽

10.1017/s0016756813000885 ◽

2013 ◽

Vol 151 (5) ◽

pp. 816-829 ◽

Cited By ~ 21

Author(s):

MAGNUS KRISTOFFERSEN ◽

TOM ANDERSEN ◽

ARILD ANDRESEN

Keyword(s):

Detrital Zircon ◽

Inductively Coupled Plasma ◽

Late Carboniferous ◽

Isotopic Signatures ◽

Inductively Coupled ◽

Source To Sink ◽

Icp Ms ◽

Plasma Mass Spectrometry ◽

Isotope Analyses ◽

Multiple Episodes

AbstractU–Pb and Lu–Hf isotope analyses of detrital zircon from the latest Ordovician (Hirnantian) Langøyene Formation, the Late Silurian Ringerike Group and the Late Carboniferous Asker Group in the Oslo Rift were obtained by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Overall the U–Pb dating yielded ages within the range 2861–313 Ma. The U–Pb age and Lu–Hf isotopic signatures correspond to virtually all known events of crustal evolution in Fennoscandia, as well as synorogenic intrusions from the Norwegian Caledonides. Such temporally and geographically diverse source areas likely reflect multiple episodes of sediment recycling in Fennoscandia, and highlights the intrinsic problem of using zircon as a tracer-mineral in ‘source to sink’ sedimentary provenance studies. In addition to its mostly Fennoscandia-derived detritus, the Asker Group also have zircon grains of Late Devonian – Late Carboniferous age. Since no rocks of these ages are known in Fennoscandia, these zircons are inferred to be derived from the Variscan Orogen of central Europe.

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Supplemental Material: Devonian to Triassic tectonic evolution and basin transition in the East Kunlun–Qaidam area, northern Tibetan Plateau: Constraints from stratigraphy and detrital zircon U–Pb geochronology

10.1130/gsab.s.16847626.v1 ◽

2021 ◽

Author(s):

Jiaopeng Sun ◽

et al.

Keyword(s):

Mass Spectrometry ◽

Detrital Zircon ◽

Tectonic Evolution ◽

Inductively Coupled Plasma ◽

Detrital Zircons ◽

Inductively Coupled ◽

Northern Tibetan Plateau ◽

East Kunlun ◽

Icp Ms ◽

Plasma Mass Spectrometry

Table S1: Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) data of detrital zircons from Carboniferous and Permian sandstones from the East Kunlun–Qaidam area; Table S2: Compilation of detrital zircon U–Pb ages used for comparison in Figure 12 from the East Kunlun–Qaidam area and its vicinity.

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Supplemental Material: Devonian to Triassic tectonic evolution and basin transition in the East Kunlun–Qaidam area, northern Tibetan Plateau: Constraints from stratigraphy and detrital zircon U–Pb geochronology

10.1130/gsab.s.16847626 ◽

2021 ◽

Author(s):

Jiaopeng Sun ◽

et al.

Keyword(s):

Mass Spectrometry ◽

Detrital Zircon ◽

Tectonic Evolution ◽

Inductively Coupled Plasma ◽

Detrital Zircons ◽

Inductively Coupled ◽

Northern Tibetan Plateau ◽

East Kunlun ◽

Icp Ms ◽

Plasma Mass Spectrometry

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Chronostratigraphic framework and provenance of the Ossa-Morena Zone Carboniferous basins (southwest Iberia)

Solid Earth ◽

10.5194/se-11-1291-2020 ◽

2020 ◽

Vol 11 (4) ◽

pp. 1291-1312

Author(s):

Manuel Francisco Pereira ◽

Cristina Gama ◽

Ícaro Dias da Silva ◽

José Brandão Silva ◽

Mandy Hofmann ◽

...

Keyword(s):

Detrital Zircon ◽

Inductively Coupled Plasma ◽

Volcanic Rocks ◽

Early Carboniferous ◽

Inductively Coupled ◽

Minimum Age ◽

Plasma Mass Spectrometry ◽

Depositional Age ◽

Siliciclastic Rocks ◽

Detrital Zircon Ages

Abstract. Carboniferous siliciclastic and silicic magmatic rocks from the Santa Susana–São Cristovão and Cabrela regions contain valuable information regarding the timing of synorogenic processes in SW Iberia. In this region of the Ossa-Morena Zone (OMZ), late Carboniferous terrigenous strata (i.e., the Santa Susana Formation) unconformably overlie early Carboniferous marine siliciclastic deposits alternating with volcanic rocks (i.e., the Toca da Moura volcano-sedimentary complex). Lying below this intra-Carboniferous unconformity, the Toca da Moura volcano-sedimentary complex is intruded and overlain by the Baleizão porphyry. Original sensitive high-resolution ion microprobe (SHRIMP) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U–Pb zircon are presented in this paper, providing chronostratigraphic and provenance constraints since available geochronological information is scarce and only biostratigraphic ages are currently available for the Santa Susana–São Cristovão region. Our findings and the currently available detrital zircon ages from Paleozoic terranes of SW Iberia (Pulo do Lobo Zone – PLZ – South Portuguese Zone – SPZ – and OMZ) were jointly analyzed using the K–S test and multidimensional scaling (MDS) diagrams to investigate provenance. The marine deposition is constrained to the age range of ca. 335–331 Ma (Visean) by new U–Pb data for silicic tuffs from the Toca da Moura and Cabrela volcano-sedimentary complexes. The Baleizão porphyry, intrusive in the Toca da Moura volcano-sedimentary complex, yielded a crystallization age of ca. 318 Ma (Bashkirian), providing the minimum age for the overlying intra-Carboniferous unconformity. A comparison of detrital zircon populations from siliciclastic rocks of the Cabrela and Toca de Moura volcano-sedimentary complexes of the OMZ suggests that they are derived from distinct sources more closely associated with the SPZ and PLZ than the OMZ. Above the intra-Carboniferous unconformity, the Santa Susana Formation is the result of the recycling of distinct sources located either on the Laurussian side (SPZ and PLZ) or Gondwanan side (OMZ) of the Rheic suture zone. The best estimate of the crystallization age of a granite cobble which was found in a conglomerate from the Santa Susana Formation yielded ca. 303 Ma (Kasimovian–Gzhelian), representing the maximum depositional age for the terrestrial strata. The intra-Carboniferous unconformity seems to represent a stratigraphic gap of approximately 12–14 Myr, providing evidence of the rapid post-accretion and collision uplift of the Variscan orogenic belt in SW Iberia (i.e., the OMZ, PLZ, and SPZ).

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Detrital zircon U–Pb ages of the Palaeozoic Natal Group and Msikaba Formation, Kwazulu-Natal, South Africa: provenance areas in context of Gondwana

Geological Magazine ◽

10.1017/s0016756815000370 ◽

2015 ◽

Vol 153 (3) ◽

pp. 460-486 ◽

Cited By ~ 8

Author(s):

CLARISA VORSTER ◽

JAN KRAMERS ◽

NIC BEUKES ◽

HERMAN VAN NIEKERK

Keyword(s):

Detrital Zircon ◽

Inductively Coupled Plasma ◽

Detrital Zircons ◽

Inductively Coupled ◽

Icp Ms ◽

Lower Ordovician ◽

Provenance Areas ◽

Geochronological Study ◽

Plasma Mass Spectrometry ◽

Ordovician Granitoids

AbstractThe Natal Group and Msikaba Formation remain relatively poorly understood with regards to their provenance and relative age of deposition; a much-needed geochronological study of the detrital zircons from these two units was therefore undertaken. Five samples of the Durban and Mariannhill Formations (Natal Group) and the Msikaba Formation (Cape Supergroup) were obtained. A total of 882 concordant U–Pb ages of detrital zircon populations from these units were determined by means of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Major Neoproterozoic and secondary Mesoproterozoic detrital zircon age populations are present in the detrital zircon content of all the samples. Smaller contributions from Archean-, Palaeoproterozoic-, Cambrian- and Ordovician-aged grains are also present. Due to the presence of a prominent major population of 800–1000 Ma zircons in all the samples, late Stenian – Tonian ancient volcanic arc complexes overprinted by Pan-African metamorphism of Mozambique, Malawi and Zambia, along with areas of similar age within Antarctica, India and Sri Lanka, are suggested as major sources of detritus. The Namaqua–Natal Metamorphic Complex is suggested as a possible source of minor late Mesoproterozoic-aged detritus. Minor populations of Archean and Palaeoproterozoic zircons were likely sourced from the Kaapvaal and Grunehogna Cratons. Post-orogenic Cambrian – Lower Ordovician granitoids of the Mozambique Belt (Mozambique) and the Maud Belt (Antarctica) made lesser contributions. In view of the apparent broad similarity of source areas for the Natal Group and Msikaba Formation, their sedimentation occurred in parts of the same large and evolving basin rather than localized in small continental basins, and the current exposures merely represent small erosional relicts.

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