scholarly journals Provenance Analysis and Structural Study of the Cycladic Blueschist Unit Rocks from Iraklia Island: From the Paleozoic Basement Unroofing to the Cenozoic Exhumation

2021 ◽  
Author(s):  
Sofia Laskari ◽  
Konstantinos Soukis ◽  
Stylianos Lozios ◽  
Daniel F. Stockli ◽  
Eirini M. Poulaki ◽  
...  
Keyword(s):  
Late Cretaceous ◽  
Detrital Zircon ◽  
Field Data ◽  
Late Triassic ◽  
Rift Basin ◽  
Provenance Analysis ◽  
Volcanic Material ◽  
Source Areas ◽  
High Pressure Metamorphism ◽  
Orogenic Events

Detailed mapping and structural observations on the Cycladic Blueschist Unit (CBU) of Iraklia island integrated by detrital zircon (DZ) U-Pb ages elucidate the Mesozoic pre-subduction evolution and the Cenozoic orogenic events. Field data reveal that the Iraklia tectonostratigraphy includes a heterogeneous Lower Schist Unit juxtaposed against a Variegated Marble Unit and an overlying Upper Schist Unit. The contact is an extensional ductile-to-brittle-ductile, top-to-N shear zone, associated with the Oligo-Miocene exhumation. The DZ spectrum of the Lower Schist Unit characterized by Gondwanan/peri-Gondwanan provenance signatures points to Late Triassic maximum depositional ages (MDAs). A quartz-rich schist layer yielded Precambrian DZ ages exclusively, considered part of the pre-Variscan metasedimentary Cycladic Basement, equivalent to those observed on Ios island. A significant change occurred during the deposition of the Upper Schist Unit, revealing Late Cretaceous MDAs and a high amount of Late Paleozoic DZ ages, attesting to more internal Pelagonian source areas. The imprint of Paleotethyan vs. Neotethyan geodynamic events is revealed in the DZ U-Pb ages record. The Triassic DZ input demonstrates eroded volcanic material related to the final Paleotethys closure and the Pindos/CBU rift basin opening. Late Cretaceous metamorphic/magmatic zircons and ~48-56 Ma zircon rims constrain the onset of subduction and high-pressure metamorphism.

scholarly journals Structural Study and Detrital Zircon Provenance Analysis of the Cycladic Blueschist Unit Rocks from Iraklia Island: From the Paleozoic Basement Unroofing to the Cenozoic Exhumation

Minerals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 83
Author(s):  
Sofia Laskari ◽  
Konstantinos Soukis ◽  
Stylianos Lozios ◽  
Daniel F. Stockli ◽  
Eirini M. Poulaki ◽  
...  
Keyword(s):  
High Pressure ◽  
Shear Zone ◽  
Late Cretaceous ◽  
Detrital Zircon ◽  
Late Triassic ◽  
Late Paleozoic ◽  
Rift Basin ◽  
Provenance Analysis ◽  
Volcanic Material ◽  
The Difference

Detailed mapping and structural observations on the Cycladic Blueschist Unit (CBU) on Iraklia Island integrated with detrital zircon (DZ) U-Pb ages elucidate the Mesozoic pre-subduction and the Cenozoic orogenic evolution. Iraklia tectonostratigraphy includes a heterogeneous Lower Schist Fm., juxtaposed against a Marble Fm. and an overlying Upper Schist Fm. The contact is an extensional ductile-to-brittle-ductile, top-to-N shear zone, kinematically associated with the Oligo-Miocene exhumation. The DZ spectra of the Lower Schist have Gondwanan/peri-Gondwanan provenance signatures and point to Late Triassic Maximum Depositional Ages (MDAs). A quartz-rich schist lens yielded Precambrian DZ ages exclusively and is interpreted as part of the pre-Variscan metasedimentary Cycladic Basement, equivalent to schists of the Ios Island core. The Upper Schist represents a distinctly different stratigraphic package with late Cretaceous MDAs and dominance of Late Paleozoic DZ ages, suggestive of a more internal Pelagonian source. The contrast in the DZ U-Pb record between Lower and Upper Schist likely reflects the difference between a Paleotethyan and Neotethyan geodynamic imprint. The Triassic DZ input from eroded volcanic material is related to the final Paleotethys closure and Pindos/CBU rift basin opening, while late Cretaceous metamorphic/magmatic zircons and ~48–56 Ma zircon rims constrain the onset of Neotethyan convergence and high-pressure subduction metamorphism.

Detrital zircon and provenance analysis of Late Cretaceous–Miocene onshore Iranian Makran strata: Implications for the tectonic setting

2016 ◽  
Vol 128 (9-10) ◽  
pp. 1481-1499 ◽  
Author(s):  
Ali Mohammadi ◽  
Jean-Pierre Burg ◽  
Wilfried Winkler ◽  
Jonas Ruh ◽  
Albrecht von Quadt
Keyword(s):  
Late Cretaceous ◽  
Detrital Zircon ◽  
Tectonic Setting ◽  
Provenance Analysis

scholarly journals Mexico: Basement framework and pre-Cretaceous stratigraphy

2020 ◽  
Author(s):  
Uwe C. Martens ◽  
Roberto S. Molina Garza
Keyword(s):  
Gulf Of Mexico ◽  
Detrital Zircon ◽  
Source Area ◽  
White Mica ◽  
Late Triassic ◽  
Source Areas ◽  
Local Character ◽  
South Central ◽  
Specific Source ◽  
Maya Mountains

ABSTRACT Provenance determinations of sediment deposited in circum–Gulf of Mexico basins rely on understanding the geologic elements present in the basement provinces located from northeast Mexico to Honduras. Relevant geologic features of these provinces are herein summarized in text and pictorial form, and they include the Huizachal-Peregrina uplift, western Gulf of Mexico, Huayacocotla, Zapoteco, Mixteca, Xolapa, Juchatengo, Cuicateco, Mixtequita, south-central Chiapas, southeast Chiapas, western Guatemala, central Guatemala, Maya Mountains, and the Chortis block. We recognized basement elements of local character that serve as fingerprints for specific source areas. However, many elements are ubiquitous, such as 1.4–0.9 Ga, high-grade metamorphic rocks that occur both as broad exposures and as inliers in otherwise reworked crust. Xenocrystic and detrital zircon of Mesoproterozoic age is very common and hence not diagnostic of provenance. Neoproterozoic rocks are very scarce in Mexican basement provinces. However, Ediacaran–Cambrian detrital zircon grains are found in Mexican Paleozoic strata; these were possibly derived from distant sources in Gondwana and Pangea. Ordovician–Silurian magmatism is present in approximately half the provinces; magmatic detrital zircon of such age is somewhat informative in terms of provenance. More useful populations are detrital zircon grains with Ordovician–Silurian metamorphic overgrowth, which seem to be mainly sourced from the Mixteca region or the southern Chiapas Massif. Devonian basement has only been discovered in the Maya Mountains of Belize, and detrital zir-on of such age seems to be characteristic of that source. A similar case can be made about Carboniferous zircon and the Acatlán Complex, Middle Pennsylvanian zircon and Juchatengo plutons, and Late Triassic zircon and the basement exposed in central Guatemala. In all these cases, the age and geographic extent of the zircon source are restricted and serve as a distinct fingerprint. Plutons of Permian–Early Triassic age are widespread, and detrital zircon grains from them are rather nonspecific indicators of source area. Future dating of detrital white mica using 40Ar-39Ar could help in recognizing Carboniferous–Triassic schist from more restricted schist occurrences such as west Cuicateco (Early Cretaceous) and central Guatemala (Late Cretaceous).

scholarly journals Use of Detrital-zircon U–Pb age-distribution Comparison to Infer Source Location

2021 ◽  
Author(s):  
Jialin Wang ◽  
Chaodong Wu ◽  
Yue Jiao ◽  
Bo Yuan
Keyword(s):  
Detrital Zircon ◽  
Age Distribution ◽  
Junggar Basin ◽  
Source Area ◽  
Source Location ◽  
Upper Triassic ◽  
Late Triassic ◽  
Provenance Analysis ◽  
Source Characteristics ◽  
Field Evidence

Abstract Provenance analysis for volcanism without field evidence remains a major challenge. Detrital zircon grains from 13 samples of the Middle–Upper Triassic Xiaoquangou Group in the Southern Junggar Basin (SJB) were analyzed using U–Pb geochronology to constrain the location and characteristics of Triassic volcanism in the area as well as to understand its tectonic implications. A comparison of the distribution of detrital zircon U–Pb ages reveals Triassic zircon ages predominate in northern Bogda Mountains, with subordinate contributions also in southern Bogda Mountains, and no or minimal input in North Tianshan piedmont. The geochronology data combined with the euhedral and angular zircon grains suggest that the Triassic zircons probably originate from Bogda Mountains. A comparative provenance analysis reveals varied sources for Xiaoquangou Group in the SJB, with sediments of the Bogda Mountains area derived mainly from North Tianshan, Central Tianshan, and Bogda Mountains. The supply of sediments from Bogda Mountains started in the Late Triassic, and is indicative of the initial uplift of Bogda Mountains. This study proves the effectiveness of the comparison of detrital zircon U–Pb age distributions for inferring source characteristics and is applicable in similar situations, particularly when the source area is poorly preserved.

So close and yet so far: U–Pb geochronological constraints of the Jaibaras Rift Basin and the intracratonic Parnaíba Basin in SW Gondwana

2021 ◽  
pp. 1-21
Author(s):  
Rodrigo I. Cerri ◽  
Lucas V. Warren ◽  
Filipe G. Varejão ◽  
Alex J. Choupina A. Silva ◽  
Cristiano Lana ◽  
...  
Keyword(s):  
Detrital Zircon ◽  
Primary Source ◽  
Rift System ◽  
Rift Basin ◽  
Source Areas ◽  
Late Cambrian ◽  
Brasiliano Orogeny ◽  
Initial Deposition ◽  
Geochronological Constraints ◽  
Parnaíba Basin

Abstract Several sag-type basins apparently developed from rift systems, but there is no consensus about how and if these grabens influenced the sedimentation of the post-rift thermal subsidence phase. The Ediacaran Jaibaras Rift Basin is one of the best-exposed sedimentary records among the NE Brazil late Precambrian – early Cambrian rift system, cropping out at the eastern margin of the intracratonic Parnaíba Basin and extending below it towards the west. Here we present detrital zircon U–Pb ages of rocks from the Jaibaras (Aprazível Formation) and Parnaíba (Ipu Formation) basins, in order to understand the provenance patterns, maximum depositional ages (MDA) and age relationship between these units. The MDA for the Aprazível Formation (c. 499 ± 5 Ma) indicates a Cambrian age for the upper part of the Jaibaras Basin. The bulk U–Pb data indicate that the Ipu Formation started to deposit during late Cambrian and/or Early Ordovician time, despite its MDA (c. 528 ± 11 Ma) being older than that of the Aprazível Formation. Detrital zircon provenance suggests that the primary source areas for the early deposits of the Parnaíba Basin were mountains related to the Brasiliano Orogeny to the south and SE (e.g. Rio Preto and Riacho do Pontal metamorphic belts). Finally, our data emphasize the key change in source areas from the rift to the initial deposition of the intracratonic phase, indicating major depositional style changes between both basins after the Gondwana assembly.

Perspectives on Cretaceous Gondwana break-up from detrital zircon provenance of southern Zealandia sandstones

2016 ◽  
Vol 154 (4) ◽  
pp. 661-682 ◽  
Author(s):  
C.J. ADAMS ◽  
H J. CAMPBELL ◽  
N. MORTIMER ◽  
W.L. GRIFFIN
Keyword(s):  
Late Cretaceous ◽  
West Coast ◽  
Detrital Zircon ◽  
Additional Source ◽  
Source Areas ◽  
South Basin ◽  
Rifted Margins ◽  
Break Up ◽  
Provenance Variations ◽  
Early Late

AbstractDetrital zircon U–Pb ages in 37 sandstones from late Early – Late Cretaceous marine and non-marine successions across southern Zealandia indicate a provenance from local basement within present-day Zealandia. Samples from Taranaki Basin were derived from Median and Karamea batholith granitoids with transport directions from west to east. Samples from West Coast, Western Southland and Great South basins contain components derived more locally and more variably from Median Batholith and Rahu Suite granitoids and/or the Palaeozoic Buller Terrane. West Coast Basin samples have more plutonic contributions and Great South Basin localities have more Albian-aged (c. 110–100 Ma) zircons. Samples from Canterbury Basin were sourced from Torlesse Composite Terrane basement. The provenance variations are present in both marine and non-marine sandstones and suggest localized watersheds. This fits an interpretation of Late Cretaceous deposition in rift-controlled basins across southern Zealandia during pre-Gondwana break-up regional extension. More speculatively, some additional source areas may have been created at the rifted margins of Zealandia during this break-up.

scholarly journals Provenance analysis of the Permo-Carboniferous fluvial sandstones of the southern part of the Boskovice Basin and the Zöbing Area (Czech Republic, Austria): implications for paleogeographical reconstructions of the post-Variscan collapse basins

2012 ◽  
Vol 63 (5) ◽  
pp. 365-382 ◽  
Author(s):  
Slavomír Nehyba ◽  
Reinhard Roetzel ◽  
Lubomír Maštera
Keyword(s):  
Chemical Weathering ◽  
Wide Spectrum ◽  
Source Area ◽  
Heavy Mineral ◽  
Minor Role ◽  
Provenance Analysis ◽  
Volcanic Material ◽  
Physical Weathering ◽  
Source Areas ◽  
Metamorphic Complexes

Abstract The provenance analyses of Permo-Carboniferous fluvial sandstones of the southern part of the Boskovice Basin and the Zöbing area are based on a wide spectrum of analytical techniques (petrography, heavy mineral assemblages, chemistry of garnet, rutile and spinel, zircon study, major and trace elements). The studied sandstones are poorly sorted and reveal a relatively immature composition implying short distance transport, rapid deposition, a high-relief source area, mainly physical weathering and the minor role of chemical weathering. Different source areas for the Boskovice Basin and the Zöbing area were proved. The Zöbing material was predominantly derived from crystalline units, mainly formed by metamorphic complexes, although the portions of magmatic and volcanic material were significant. The source area is supposed to be located in the Moldanubian Unit. The Boskovice Basin deposits, on the other hand, seem to be mainly derived from metamorphic complexes, corresponding especially to the Moravian Unit, with a relatively wider spectrum of metamorphites, together with the derivation of the detritus from pre-existing sedimentary rocks (especially from Moravo- Silesian Paleozoic deposits/Drahany Culm unit). The transport direction in the basin was more complex, both from the west and east. These results did not confirm the possibility of communication between the Boskovice Basin and the Zöbing area during the Late Paleozoic. The existence of “colinear” marginally offset half grabens with predominant transversal sources is here hypothesized. The general heavy mineral evolution in time does not indicate the successive exhumation of a simple structured orogen but may be interpreted as differences in the extent of the source areas.

Sign in / Sign up

Export Citation Format

Share Document