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

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

10.5194/se-2020-26 ◽

2020 ◽

Author(s):

M. Francisco Pereira ◽

Cristina Gama ◽

Ícaro Dias da Silva ◽

José B. Silva ◽

Mandy Hofmann ◽

...

Keyword(s):

Detrital Zircon ◽

Volcanic Rocks ◽

Early Carboniferous ◽

Suture Zone ◽

Magmatic Rocks ◽

Icp Ms ◽

Minimum Age ◽

Depositional Age ◽

Siliciclastic Rocks ◽

Detrital Zircon Ages

Abstract. Carboniferous siliciclastic and silicic magmatic rocks from the Santa Susana-São Cristovão region 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 SHRIMP and 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 MDS diagrams to investigate provenance. The marine deposition is constrained to the age interval of c. 335–331 Ma (Visean) by new U-Pb data for silicic tuffs from the Toca da Moura volcano-sedimentary complex. The Baleizão porphyry, intrusive in the Toca da Moura volcano-sedimentary complex, yielded a crystallization age of c. 317 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 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 either the result of the recycling of distinct sources located in the Laurussian-side (SPZ and PLZ) and Gondwanan-side (OMZ) of the Rheic suture zone. The best estimate of the crystallization age of a granite cobble found in a conglomerate from the Santa Susana Formation yielded c. 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 Ma, providing evidence of the rapid post-accretion/collision uplift of the Variscan orogenic belt in SW Iberia (i.e. the OMZ, PLZ and SPZ).

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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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Basic volcanism contemporaneous with the Sturtian glacial episode in NE Scotland

Earth and Environmental Science Transactions of the Royal Society of Edinburgh ◽

10.1017/s1755691009009037 ◽

2009 ◽

Vol 100 (04) ◽

pp. 399-415 ◽

Cited By ~ 8

Author(s):

David M. Chew ◽

Nicola Fallon ◽

Christine Kennelly ◽

Quentin Crowley ◽

Michael Pointon

Keyword(s):

Detrital Zircon ◽

Inductively Coupled Plasma ◽

Inductively Coupled ◽

Basement Rocks ◽

Metavolcanic Rocks ◽

Icp Ms ◽

Plasma Mass Spectrometry ◽

Depositional Age ◽

Group Boundary ◽

Southern Highland

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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Further detrital zircon evidence for peri-Gondwanan blocks in the central Appalachian Piedmont Province, USA

Canadian Journal of Earth Sciences ◽

10.1139/cjes-2018-0253 ◽

2019 ◽

Vol 56 (10) ◽

pp. 1061-1076

Author(s):

Aaron J. Martin ◽

Howell Bosbyshell

Keyword(s):

Detrital Zircon ◽

Inductively Coupled Plasma ◽

Mass Spectrometry Data ◽

Sediment Provenance ◽

Inductively Coupled ◽

Depleted Mantle ◽

Plasma Mass Spectrometry ◽

Appalachian Piedmont ◽

Detrital Zircon Ages ◽

Piedmont Province

Evidence for exotic terranes in the central Appalachian Piedmont Province is fragmented between central Virginia, northern Maryland, and southeastern Pennsylvania. Here we present laser ablation-inductively coupled plasma mass spectrometry data from detrital zircon that support the presence of an exotic terrane in this region. U–Pb dating of detrital zircon from new samples of the Storck quartzite (central Virginia) and the Hoods Mill rocks (northern Maryland) confirms the presence of a major peak at ca. 630–610 Ma in these units. These ages are consistent with derivation from Gondwana, but not Ediacaran Laurentia. Further, modern εHf values of five of the ca. 670–580 Ma grains in these samples are inconsistent with derivation from the few plutons of this age in Ediacaran Laurentia. The Loch Raven Schist and a metasedimentary xenolith in the Wilmington Complex contain a smaller proportion of ca. 670–580 Ma grains than the Storck quartzite and the Hoods Mill rocks, but more such grains than in sediment derived from Ediacaran Laurentia, so we tentatively conclude that these two units also received sediment from Gondwana. Detrital zircon ages from the Piney Run Formation, Pleasant Grove Schist, Prettyboy Schist, and Wissahickon Formation allow sediment provenance solely in Ediacaran Laurentia. We also present new zircon spot U–Pb and Lu–Hf isotopic data from western Newfoundland plutons for comparison with these types of data from the detrital zircon. Intrusion ages of the Steel Mountain Anorthosite, Disappointment Hill Tonalite, and Round Pond Granite are 608 ± 12, 600 ± 8, and 590 ± 9 Ma, respectively. None of these units was derived entirely from the depleted mantle.

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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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Distribution of gallium between phenocrysts and melt in peralkaline salic volcanic rocks, Kenya Rift Valley

Mineralogical Magazine ◽

10.1180/minmag.2010.074.2.351 ◽

2010 ◽

Vol 74 (2) ◽

pp. 351-363 ◽

Cited By ~ 6

Author(s):

R. Macdonald ◽

N. W. Rogers ◽

B. Bagiński ◽

P. Dzierżanowski

Keyword(s):

Rift Valley ◽

Inductively Coupled Plasma ◽

Magma Mixing ◽

Volcanic Rocks ◽

Alkali Feldspar ◽

Volcanic Complex ◽

Kenya Rift ◽

Inductively Coupled ◽

Plasma Mass Spectrometry ◽

Kenya Rift Valley

AbstractGallium abundances, determined by laser ablation-inductively coupled plasma-mass spectrometry, are presented for phenocrysts and glassy matrices from a metaluminous trachyte and five peralkaline rhyolites from the Greater Olkaria Volcanic Complex, Kenya Rift Valley. Abundances in the glasses range from 28.9 to 33.3 ppm, comparable with peralkaline rhyolites elsewhere. Phenocryst Ga abundances (in ppm) are: sanidine 31.5–45.3; fayalite 0.02–0.22; hedenbergite 3.3–6.3; amphibole 12; biotite 72; ilmenite 0.56–0.72; titanomagnetite 32; chevkinite-(Ce) 364. The mafic phases and chevkinite-(Ce) are enriched in Ga relative to Al, whereas Ga/Al ratios in sanidine are smaller than in coexisting glass. Apparent partition coefficients range from <0.01 in fayalite to 12 in chevkinite-(Ce). Coefficients for hedenbergite, ilmenite and titanomagnetite decrease as melts become peralkaline. The sharp increase in Ga/Al in the more fractionated members of alkaline magmatic suites probably results from alkali feldspar-dominated fractionation. Case studies are presented to show that the Ga/Al ratio may be a sensitive indicator of such petrogenetic processes as magma mixing, interaction of melts with F-rich volatile phases, mineral accumulation and volatile-induced crustal anatexis.

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Hydrogeochemistry and lead contamination of groundwater in the north part of Esfahan province, Iran

Journal of Water and Health ◽

10.2166/wh.2018.034 ◽

2018 ◽

Vol 16 (4) ◽

pp. 622-634 ◽

Cited By ~ 3

Author(s):

Kaveh Pazand ◽

Davoud Khosravi ◽

Mohammad Reza Ghaderi ◽

Mohammad Reza Rezvanianzadeh

Keyword(s):

Inductively Coupled Plasma ◽

Arid Regions ◽

Volcanic Rocks ◽

Primary Source ◽

Lead Contamination ◽

Inductively Coupled ◽

The North ◽

Icp Ms ◽

North Part ◽

Plasma Mass Spectrometry

Abstract Geochemical and hydrogeochemical studies were conducted to assess the origin and geochemical mechanisms driving lead enrichment in groundwaters of semi-arid regions in Central Iran. In this study, 149 water samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). Concentrations of Pb and As in about 68% and 27% of the samples, respectively, exceeded WHO guidelines. Analyzing the results of ICP-MS of parental rocks and aquifer sediments shows that unweathered volcanic rocks were the primary source for lead mobilizing to groundwaters.

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