Jurassic arc volcanism on Crimea (Ukraine): Implications for the paleo-subduction zone configuration of the Black Sea region

Meijers, M. J. M.
Vrouwe, B.
van Hinsbergen, D. J. J.
Kuiper, K. F.
Wijbrans, J.
Davies, G. R.
Stephenson, R. A.
Kaymakcı, Nuretdin
Matenco, L.
Saintot, A.
The early Cretaceous and younger opening of the Black Sea has obliterated much of the older record of Tethyan subduction below southeastern Europe. The earlier Mesozoic evolution was dominated by opening and closure of Tethyan oceans between Gondwana and Laurasia with their consumption, at least in part, accommodated along the southern Eurasian margin. Crimea (Ukraine), a peninsula in the northern Black Sea, represents the northernmost region of southeastern Europe that exposes a record of a pre-Cretaceous Tethyan active margin. To shed new light on the paleosubduction zone configuration of the southeastern European margin in the Jurassic, we report Ar-40/Ar-39 isotope dating on 10 samples and whole rock geochemistry on 31 samples from supposedly Jurassic magmatic rocks from the Crimean peninsula. The samples can be subdivided into two age groups: middle Jurassic (similar to 172-158 Ma) and uppermost Jurassic to lowermost Cretaceous (similar to 151-142 Ma), that both have a subduction-related geochemical signature. The ages of the younger group are in conflict with previously assigned biostratigraphic ages of the units under- and overlying the volcanic complex. This might suggest a scenario where the latter were juxtaposed by faulting. We argue that the Crimean volcanics represent a fragment of a volcanic arc overlying the southeastern European continental margin. These data therefore provide evidence for Jurassic northwards subduction below the Eurasian margin, preceding the opening of the Black Sea as a back-arc basin. We argue that the corresponding Jurassic trench was already positioned south of the Turkish Pontides and the Caucasus belt, implying a very shallow slab angle in the Jurassic.


Late Cretaceous-Eocene Geological Evolution of the Pontides Based on New Stratigraphic and Palaeontologic Data Between the Black Sea Coast and Bursa (NW Turkey)
Ozcan, Zahide; Okay, Aral; Özcan, Ercan; Hakyemez, Aynur; Altıner, Sevinç (2012-01-01)
The Late Cretaceous-Eocene geological evolution of northwest Turkey between the Black Sea and Bursa was studied through detailed biostratigraphic characterization of eleven stratigraphic sections. The Upper Cretaceous sequence in the region starts with a major marine transgression and lies unconformably on a basement of Palaeozoic and Triassic rocks in the north (Istanbul-type basement) and on metamorphic rocks and Jurassic sedimentary rocks in the south (Sakarya-type basement). Four megasequences have been...
Cretaceous pelagic red beds and black shales (Aptian-Santonian), NW Turkey: Global oceanic anoxic and oxic events
Yılmaz, İsmail Ömer (2008-04-01)
The study areas located near the towns of Goynok, Muclurnu and Nallihan in the central northwestern part of Turkey lie on the 'Sakarya Continent', which is one of the tectonic entities of the Cretaceous geology of Turkey. Measured stratigraphic sections comprise the Aptian pelagic carbonates and the overlying Albian-Coniacian turbiditic sequences, which are all capped by a Late Santonian red pelagic succession. Lower and Upper Aptian, Upper Albian and Cenomanian/Turonian marine black shales recognized in th...
The Unaz Formation: A Key Unit in the Western Black Sea Region, N Turkey
Tuysuz, Okan; Yılmaz, İsmail Ömer; Svabenicka, Lilian; Kirici, Sabri (2012-01-01)
The Pontide magmatic belt in the Western Pontides, which developed in response to the northward subduction of the northern branches of the Tethys Ocean, consists of two different volcanic successions separated by an Upper Santonian pelagic limestone unit, the Unaz Formation. The first period of volcanism and associated sedimentation started during the Middle Turonian and lasted until the Early Santonian under the control of an extensional tectonic regime, which created horst-graben topography along the sout...
Age and geodynamic evolution of the Black Sea Basin: Tectonic evidences of rifting in Crimea
Hippolyte, Jean-Claude; Murovskaya, Anna; Volfman, Yuri; Yegorova, Tamara; Gintov, Oleg; Kaymakcı, Nuretdin; SANĞU, ERCAN (2018-05-01)
The timing and direction of opening of the Black Sea Basin are debated. However, parts of its margins were inverted during Cenozoic and can be studied onshore. The Crimean Mountains are located in the middle of the northern margin of the basin, and at the onshore prolongation of the mid-Black Sea High.
Cretaceous black shales (Oceanic Anoxic Events) in Turkey:collaboration of tectonics, sea level and oceanographic changes
Yılmaz, İsmail Ömer (null; 2017-08-26)
Cretaceous oceanic anoxic events are recorded as black shale deposits in Mid-Barremian, Aptian, Cenomanian/Turonian stages in different basins in Turkey. The Mid-Barremian black shales (MBE) have been recorded within a turbidite succession in a deep marine setting in central Sakarya zone of Pontides (YILMAZ et al., 2012). 2 ‰ shifts in the carbon isotope curve are recorded in parallel with European basins, but with low TOC values. The Aptian black shales (OAE1a) are recorded in pelagic carbonate slope envir...
Citation Formats
M. J. M. Meijers et al., “Jurassic arc volcanism on Crimea (Ukraine): Implications for the paleo-subduction zone configuration of the Black Sea region,” LITHOS, pp. 412–426, 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/36881.