scholarly journals Provenance analysis of the Paleozoic sequences of the northern Gondwana margin in NW Iberia: Passive margin to Variscan collision and orocline development

2013 ◽  
Vol 23 (3) ◽  
pp. 1089-1103 ◽  
Author(s):  
Daniel Pastor-Galán ◽  
Gabriel Gutiérrez-Alonso ◽  
J. Brendan Murphy ◽  
Javier Fernández-Suárez ◽  
Mandy Hofmann ◽  
...  
Keyword(s):  
Passive Margin ◽  
Provenance Analysis ◽  
Nw Iberia ◽  
Gondwana Margin

Detrital zircon geochronology of Ediacaran to Cambrian deep-water strata of the Franklinian basin, northern Ellesmere Island, Nunavut: implications for regional stratigraphic correlations

2013 ◽  
Vol 50 (10) ◽  
pp. 1007-1018 ◽  
Author(s):  
Luke P. Beranek ◽  
Victoria Pease ◽  
Robert A. Scott ◽  
Tonny B. Thomsen
Keyword(s):  
Shallow Water ◽  
Deep Water ◽  
Detrital Zircon ◽  
Detrital Zircons ◽  
Ellesmere Island ◽  
Passive Margin ◽  
Sediment Provenance ◽  
Provenance Analysis ◽  
Detrital Zircon Geochronology ◽  
Detrital Zircon Ages

Enigmatic successions of deep-water strata referred to as the Nesmith beds and Grant Land Formation comprise the exposed base of the Franklinian passive margin sequence in northern Ellesmere Island, Nunavut. To test stratigraphic correlations with Ediacaran to Cambrian shallow-water strata of the Franklinian platform that are inferred by regional basin models, >500 detrital zircons from the Nesmith beds and Grant Land Formation were analyzed for sediment provenance analysis using laser ablation (LA–ICP–MS) and ion-microprobe (SIMS) methods. Samples of the Nesmith beds and Grant Land Formation are characterized by 1000–1300, 1600–2000, and 2500–2800 Ma detrital zircon age distributions and indicate provenance from rock assemblages of the Laurentian craton. In combination with regional stratigraphic constraints, these data support an Ediacaran to Cambrian paleodrainage model that features the Nesmith beds and Grant Land Formation as the offshore marine parts of a north- to northeast-directed depositional network. Proposed stratigraphic correlations between the Nesmith beds and Ediacaran platformal units of northern Greenland are consistent with the new detrital zircon results. Cambrian stratigraphic correlations within northern Ellesmere Island are permissive, but require further investigation because the Grant Land Formation provenance signatures agree with a third-order sedimentary system that has been homogenized by longshore current or gravity-flow processes, whereas coeval shallow-water strata yield a restricted range of detrital zircon ages and imply sources from local drainage areas or underlying rock units. The detrital zircon signatures of the Franklinian passive margin resemble those for the Cordilleran and Appalachian passive margins of Laurentia, which demonstrates the widespread recycling of North American rock assemblages after late Neoproterozoic continental rifting and breakup of supercontinent Rodinia.

Fragmentation of South China from greater India during the Rodinia-Gondwana transition

Geology ◽  
2020 ◽  
Author(s):  
Wei Wang ◽  
Peter A. Cawood ◽  
Manoj K. Pandit ◽  
Xiaoping Xia ◽  
Massimo Raveggi ◽  
...  
Keyword(s):  
South China ◽  
Detrital Zircon ◽  
Time Window ◽  
Passive Margin ◽  
Simultaneous Increase ◽  
Northwestern India ◽  
Sedimentary Sequences ◽  
Northwestern Margin ◽  
Gondwana Margin ◽  
T Values

Late Tonian to Cambrian sedimentary sequences in northwestern India and South China provide vital evidence for modeling their paleogeographic linkage, including their juxtaposition and subsequent separation during the transition from the Rodinia to the Gondwana supercontinents. Similarities in lithostratigraphy and detrital zircon U-Pb-Hf-O isotopic characteristics in the late Tonian sedimentary units from both regions underline a common provenance. A substantial decrease in zircon δ18O values from super- to sub-mantle compositions and simultaneous increase in the zircon εHf(t) values in South China and northwestern India for the 800–700 Ma time window suggest a common Neoproterozoic extensional magmatic event, corresponding with the Rodinia breakup. A distinct change in sedimentary provenance is noted during the Cryogenian period. Sedimentation along the northwestern margin of India for the remainder of the Neoproterozoic encompasses large volumes of clastic detritus dominated by old zircon ages, derived inboard from the Indian craton. In contrast, contemporaneous sedimentary units in the Yangtze region of South China are dominated by Neoproterozoic zircons. The detrital zircon age data underline a close paleogeographic linkage between northwestern India and South China (Yangtze and Cathaysia regions) in the Rodinia supercontinent configuration and argue for their separation through continental rifting during the Cryogenian. Northwestern India developed into a passive margin, whereas the South China block partially rifted, rotated, and migrated dextrally along the Gondwana margin toward northeastern India and Western Australia, such that the Cathaysia block continued to receive detritus from Gondwana continental regions.

Relationships between syn-orogenic sedimentation and nappe emplacement in the hinterland of the Variscan belt in NW Iberia deduced from detrital zircons

2015 ◽  
Vol 153 (1) ◽  
pp. 38-60 ◽  
Author(s):  
JOSÉ R. MARTÍNEZ CATALÁN ◽  
EMILIO GONZÁLEZ CLAVIJO ◽  
CARLOS MEIRELES ◽  
RUBÉN DÍEZ FERNÁNDEZ ◽  
JAMES BEVIS
Keyword(s):  
Structural Study ◽  
Inductively Coupled Plasma ◽  
Structural Evolution ◽  
Detrital Zircons ◽  
Passive Margin ◽  
Variscan Belt ◽  
Limited Participation ◽  
Inductively Coupled ◽  
Nw Iberia ◽  
Nappe Emplacement

AbstractFlysch-type, syn-orogenic deposits of Carboniferous age occur in relation to the emplacement of a large allochthonous nappe stack in the Variscan belt of NW Iberia. New U–Pb age populations of detrital zircons obtained using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) are considered together with others from previously dated samples to establish the relationships between sedimentation and thrusting. The age populations of four syn-orogenic formations are compared with those of the pre-orogenic sequence in the Autochthon and Parautochthon, representing the Gondwanan passive margin, and in the Allochthon, formed by peri-Gondwanan and oceanic terranes. In addition, a new structural study has been carried out to understand the relationships between the syn-orogenic deposits and the development of Variscan structures. The aims are to identify the sources of sediments and to establish the relationship between Variscan structural evolution and syn-orogenic sedimentation. Development of a forebulge outwards from the allochthonous front, deduced from the structural study, suggests the existence of depocentres that hosted the syn-orogenic sediments. Together with the trend shown by the more recent zircons in each formation, that are younger towards the external zones, the data suggest that sedimentation occurred in progressively migrating depocentres formed in front of the allochthonous wedge during its emplacement. The zircon age populations point to the Allochthon as the main source of detritus for the syn-orogenic basins, with perhaps a limited participation of the Parautochthon and Autochthon in the younger formations.

scholarly journals Hidden Middle Devonian Magmatism of North-Eastern Siberia: Age Constraints from Detrital Zircon U–Pb Data

Minerals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 874
Author(s):  
Victoria B. Ershova ◽  
Andrei V. Prokopiev ◽  
Andrei K. Khudoley
Keyword(s):  
Detrital Zircon ◽  
Middle Devonian ◽  
Passive Margin ◽  
Large Igneous Province ◽  
Late Devonian ◽  
Eastern Siberia ◽  
Provenance Analysis ◽  
Fold And Thrust Belt ◽  
North Eastern ◽  
Middle Paleozoic

We present new data on the tectonic evolution of north-eastern Siberia using an integrated provenance analysis based on U–Pb detrital zircon dating and sandstone petrography of Devonian sedimentary strata. Our petrographic data suggest that Upper Devonian sandstones of north-eastern Siberia were derived from a local provenance, supported by the widespread distribution of ca. 1900–2000 Ma magmatic events in the basement of the neighboring Ust’-Lena and Olenek uplifts. Devonian detrital zircon age distributions of the Devonian sandstones are similar to ages of Middle Paleozoic magmatic rocks of Yakutsk-Vilyui large igneous province (LIP). Therefore, we suggest that the studied sandstones were derived from proximally-located uplifted blocks composed of Proterozoic–Devonian rocks and Middle–Late Devonian volcanics. Moreover, the abundance of Middle–Late Devonian zircons is suggestive of a wider distribution of coeval magmatism across north-eastern Siberia than previously supposed. We propose that widespread Devonian magmatism associated with the Yakutsk-Vilyui LIP also occurred to the east of our study area and is now buried beneath thick Carboniferous–Jurassic sedimentary rocks of the eastern Siberian passive margin, subsequently deformed into the Late Jurassic–Cretaceous Verkhoyansk fold-and-thrust belt. We also propose that the major pulse of the Yakutsk-Vilyui LIP occurred in north-eastern Siberia during the Middle Devonian at ca. 390 Ma, some 15 million years earlier than within the Vilyui rift basin in eastern Siberia (ca. 375 Ma).

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