The central-western Getic Carbonate Platform: Upper Jurassic to Lower Cretaceous biostratigraphy and sedimentary evolution of the Cioclovina–Băniţa sector (Southern Carpathians, Romania)

Facies ◽  
2019 ◽  
Vol 65 (3) ◽  
Author(s):  
George Pleş ◽  
Alin Oprişa ◽  
Ioan I. Bucur ◽  
Emanoil Săsăran ◽  
Cristian V. Mircescu ◽  
...  
Keyword(s):  
Lower Cretaceous ◽  
Carbonate Platform ◽  
Upper Jurassic ◽  
Sedimentary Evolution ◽  
Southern Carpathians

scholarly journals An Upper Jurassic-Lower Cretaceous carbonate platform from the Vâlcan Mountains (Southern Carpathians, Romania): paleoenvironmental interpretation

2012 ◽  
Vol 63 (1) ◽  
pp. 33-48 ◽  
Author(s):  
Mihai Michetiuc ◽  
Camelia Catincuţ ◽  
Ioan Bucur
Keyword(s):  
Lower Cretaceous ◽  
Carbonate Platform ◽  
Upper Jurassic ◽  
High Energy ◽  
Environmental Interpretation ◽  
Paleoenvironmental Interpretation ◽  
Marine Facies ◽  
Definition Of ◽  
Shallow Carbonate Platform ◽  
Southern Carpathians

An Upper Jurassic-Lower Cretaceous carbonate platform from the Vâlcan Mountains (Southern Carpathians, Romania): paleoenvironmental interpretationThe results of a biostratigraphic and sedimentological study of the Upper Jurassic-Lower Cretaceous limestones cropping out in the southern sector of the Vâlcan Mountains in Romania are presented, including the definition of microfacies types, fossil assemblages and environmental interpretation. Six microfacies types (MFT 1-MFT 6) have been identified, each of them pointing to a specific depositional environment. The deposits are characteristic of a shallow carbonate platform. They contain normal marine or restricted marine facies deposited in low or high energy environments from the inner, middle and outer platform. The age attribution of these deposits (Late Jurassic to Berriasian-Valanginian-?Hauterivian, and Barremian) is based on foraminiferal and calcareous algae associations. The micropaleontological assemblage is exceptionally rich in the Vâlcan Mountains and brings new arguments for dating the Upper Jurassic-Lower Cretaceous limestones in this area.

Mesozoic palaeogeography and tectono-stratigraphic features of the northern Amerini Mts. (Central Apennines, Italy): new constraints on their Jurassic and Cretaceous evolution

2020 ◽  
Author(s):  
Costantino Zuccari ◽  
Angelo Cipriani ◽  
Massimo Santantonio
Keyword(s):  
Early Cretaceous ◽  
Lower Cretaceous ◽  
Carbonate Platform ◽  
Indirect Evidence ◽  
Lower Jurassic ◽  
Geological Mapping ◽  
Carbonate Platforms ◽  
Central Apennines ◽  
Sedimentary Evolution ◽  
Structural High

<p>A geological mapping project was performed on the 1:10,000 scale in the northern Amerini Mts. (Narni–Amelia Ridge, Central Apennines), coupled with facies analysis and multidisciplinary outcrop characterisation. This project was focused on the Jurassic-Lower Cretaceous succession, in order to reconstruct the Mesozoic palaeogeography and tectono-sedimentary evolution of the study area. This sector of the Apenninic Chain (i.e. Umbria-Marche-Sabina palaeogeographic domain) experienced the Early Jurassic rifting phase, which dismembered the vast Calcare Massiccio carbonate platform. The development of a rugged submarine topography, coupled with drowning of the benthic factories, were the main effects of this normal faulting. The complex submarine physiography, made of structural highs and lows, is highlighted by facies and thickness variations of the Jurassic and Lower Cretaceous deposits. The hangingwall blocks hosted thick (hundreds of metres) pelagic successions, with variable volumes of admixed gravity-flow deposits. These successions onlapped the horst blocks along escarpments, rooted in the rift faults, where the pre-rift Calcare Massiccio was exposed. The tops of footwall blocks (Pelagic Carbonate Platforms or PCPs) were capped by thin (few tens of metres or less), fossil-rich and chert-free, condensed pelagic successions. This rift architecture was evened out at a domain scale in the Early Cretaceous. Successively, Miocene orogenic and Plio-Pleistocene extensional faulting caused uplift and exhumation of the Mesozoic rocks.</p><p>In the study area, geothematic mapping associated with the analysis of basin-margin unconformities and successions revealed a narrow and elongated Jurassic structural high (Mt. Croce di Serra - Mt. Alsicci structural high), surrounded by Jurassic basinal pelagites. The PCP-top condensed succession is not preserved. The chert-rich basinal units rest on the horst-block Calcare Massiccio through unconformity surfaces (palaeoescarpments), as marked by the silicification of the (otherwise chert-free) shallow-water limestone. The onlap successions embed megablocks of Calcare Massiccio (hundreds of metres across), detached from their parent palaeoescarpments. Very thin, condensed deposits form discontinuous veneers on the olistoliths of Calcare Massiccio (epi-olistolith deposits) and are onlapped by younger basin-fill pelagites. The beds surrounding the olistoliths are characteristically bent due to differential compaction, as their (newly acquired) strikes mimic the outline of the stiff objects they were burying.</p><p>Indirect evidence for a Toarcian, post-rift, tectonic pulse can be locally mapped, and is documented by angular unconformities between the Pliensbachian and Toarcian pelagites, as well as by mass-transport deposits found in the Rosso Ammonitico (Toarcian).</p><p>The same goes for millimetric to centimetric neptunian dykes made of Maiolica pelagites cross-cutting the Corniola Fm. (Sinemurian-Pliensbachian). These dykes, coupled with the occurrence of unconformities between Aptian-Albian pelagites (Marne a Fucoidi Fm.) and Lower Jurassic rocks (Calcare Massiccio and Corniola formations), provide evidence for a further Early Cretaceous tectonic phase, recently reported from the southern sectors of Narni-Amelia ridge.</p>

scholarly journals THE LATE EARLY CRETACEOUS TRANSGRESSION ON THE LATERITES IN VOURINOS AND VERMION MASSIFS (WESTERN MACEDONIA, GREECE)

2018 ◽  
Vol 40 (1) ◽  
pp. 182 ◽  
Author(s):  
A. Photiades ◽  
N. Carras ◽  
V. Bortolotti ◽  
M. Fazzuoli ◽  
G. Principi
Keyword(s):  
Early Cretaceous ◽  
Lower Cretaceous ◽  
Upper Cretaceous ◽  
Carbonate Platform ◽  
Upper Jurassic ◽  
Ophiolite Complex ◽  
Marine Transgression ◽  
The Third ◽  
Normal Salinity

Three stratigraphical sections from eastern Vourinos (Rhodiani area) to eastern Vermion massifs revealed the same age of the latérite events affecting the serpentinized ophiolite complex after its emplacement on the Pelagonian domain. All of them consist from their base upwards of serpentinized harzburgite slivers with lateritic unconformities on the top, followed by transgressive upper Lower Cretaceous neritic limestones. At Kteni locality (Rhodiani area), a laterite horizon, lying on top of serpentinites, is covered by transgressive neritic limestones with Salpingoporella urladanasi, assigning a Barremian - Albian age, followed by Orbitolinidae limestones. At Tsimodia locality (NNW to the previous), the latente horizon, lying on karstified Upper Jurassic reef limestones (which are the top member of a carbonate platform body tectonically lying on the ophiolites), is trans gres s ively overlain by iron-rich pisolith levels and Aptian limestones of the wackes tone-muds tone type, also containing Salpingoporella urladanasi, followed by Cenomanian Orbitolina limestones. Finally, the third examined locality, further north-eastward to the previous, is situated at the eastern slopes of Vermion massif and more precisely at the NWpart of Koumaria village. There, it can again be observed that the lateritized serpentinite slivers are overlain transgress ively by neritic limestones with Salpingoporella urladanasi, passing upwards into Upper Cretaceous recrystallized limestones with Orbitolinidae and rudist fragments and, finally, toflysch deposition. These features allow to recognize that the emersion and the consecutive lateritization of the thrust-emplaced ophiolites in Vourinos and Vermion massifs in the northern Pelagonian domain, starting from the Latest Jurassic, was followed by a marine transgression beginning from the Barremian - Albian, firstly under restricted and brackish carbonate platform conditions, marked by the presence of the dasycladalean alga Salpingoporella urladanasi, followed by normal salinity carbonate platform conditions. The neritic sedimentation was stable until the Early Cenomanian. Subsequently, a deepening, earlier at Vourinos and later at Vermion, resulted in deposition of pelagic and turbiditic carbonates and then offlysch.

Geochemical characteristics of Upper Jurassic – Lower Cretaceous platform carbonates in Hazine Mağara, Gümüşhane (northeast Turkey): implications for dolomitization and recrystallization

2019 ◽  
Vol 56 (3) ◽  
pp. 306-320 ◽  
Author(s):  
Merve Özyurt ◽  
M. Ziya Kırmacı ◽  
Ihsan S. Al-Aasm
Keyword(s):  
Lower Cretaceous ◽  
Carbonate Platform ◽  
Upper Jurassic ◽  
Close Proximity ◽  
Post Archean Australian Shale ◽  
History Of ◽  
Polymetallic Mineralization ◽  
Platform Carbonates ◽  
Geochemical Studies ◽  
Ree Patterns

The Upper Jurassic – Lower Cretaceous Berdiga Formation of the Eastern Pontides, Turkey, represents a carbonate platform succession composed of pervasively dolomitized intra-shelf to deep-shelf facies. In this area, polymetallic deposits occur as veins and lenses within the Berdiga Formation in close proximity to its upper contact with the overlying formation. Three different types of replacive dolomites occur in the formation: (i) microcrystalline dolomite, (ii) fabric-preserving dolomite, and (iii) fabric-destructive dolomite. Replacive dolomites are Ca rich and nonstoichiometric (Ca56–58Mg42–44) and are characterized by a pronounced negative shift in oxygen (–11.38‰ to –4.05‰ Vienna Pee Dee Belemnite (VPDB)), δ13C values of 0.69‰ to 3.13‰ VPDB, radiogenic 87Sr/86Sr ratios (0.70753 to 0.70884), and extremely high Fe (2727–21 053 ppm) and Mn (1548–27 726 ppm) contents. All dolomite samples have low Y/Ho ratios (23–40), and they also contain highly variable contents of rare earth elements (REE) (7–41). REE patterns of dolomites normalized to Post-Archean Australian shale show a distinct positive Eu anomaly (1.3–2.1) and slightly flattened Ce anomalies (0.8–1.1). Integration of petrographic and geochemical studies reveals the history of a variety of diagenetic processes highly affected by hydrothermal alteration, which include dolomitization, recrystallization, dissolution, silicification, and pyrite mineralization associated with the emplacement of the polymetallic mineralization.

scholarly journals The ophiolite-related Mersin Melange, southern Turkey: its role in the tectonic–sedimentary setting of Tethys in the Eastern Mediterranean region

2004 ◽  
Vol 141 (3) ◽  
pp. 257-286 ◽  
Author(s):  
OSMAN PARLAK ◽  
ALASTAIR ROBERTSON
Keyword(s):  
Lower Cretaceous ◽  
Upper Cretaceous ◽  
Carbonate Platform ◽  
Eastern Mediterranean ◽  
Eastern Mediterranean Region ◽  
Leading Edge ◽  
Vertical Axis ◽  
Upper Jurassic ◽  
Passive Margin ◽  
Southern Turkey

The Mersin Melange underlies the intact Mersin Ophiolite and its metamorphic sole to the south of the Mesozoic Tauride Carbonate Platform in southern Turkey. The Melange varies from chaotic melange to broken formation, in which some stratigraphic continuity can be recognized. Based on study of the broken formation, four lithological associations are recognized: (1) shallow-water platform association, dominated by Upper Palaeozoic–Lower Cretaceous neritic carbonates; (2) rift-related volcanogenic–terrigenous–pelagic association, mainly Upper Triassic andesitic–acidic volcanogenic rocks, siliciclastic gravity flows, basinal carbonates and radiolarites; (3) within-plate-type basalt–radiolarite–pelagic limestone association, interpreted as Upper Jurassic–Lower Cretaceous seamounts with associated radiolarian sediments and Upper Cretaceous pelagic carbonates; (4) ophiolite-derived association, including fragments of the Upper Cretaceous Mersin Ophiolite and its metamorphic sole. Locally, the ophiolitic melange includes granite that yielded a K/Ar radiometric age of 375.7±10.5 Ma (Late Devonian). This granite appears to be subduction influenced based on ‘immobile’ element composition.The Mersin Melange documents the following history: (1) Triassic rifting of the Tauride continent; (2) Jurassic–Cretaceous passive margin subsidence; (3) oceanic seamount genesis; (4) Cretaceous supra-subduction zone ophiolite genesis; (5) Late Cretaceous intra-oceanic convergence-metamorphic sole formation, and (6) latest Cretaceous emplacement onto the Tauride microcontinent and related backthrusting.Regional comparisons show that the restored Mersin Melange is similar to the Beyşehir–Hoyran Nappes further northwest and a northerly origin best fits the regional geological picture. These remnants of a North-Neotethys (Inner Tauride Ocean) were formed and emplaced to the north of the Tauride Carbonate Platform. They are dissimilar to melanges and related units in northern Syria, western Cyprus and southwestern Turkey, which are interpreted as remnants of a South-Neotethys. Early high-temperature ductile transport lineations within amphibolites of the metamorphic sole of the Mersin ophiolite are generally orientated E–W, possibly resulting from vertical-axis rotation of the ophiolite while still in an oceanic setting. By contrast, the commonly northward-facing later stage brittle structures are explained by backthrusting of the ophiolite and melange related to exhumation of the partially subducted northern leading edge of the Tauride continent.

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