Mineralogic evidences of a mid-Paleozoic tectono-thermal event in the Zonguldak terrane, northwest Turkey: implications for the dynamics of some Gondwana-derived terranes during the closure of the Rheic Ocean

Bozkaya, Omer
Göncüoğlu, Mehmet Cemal
The Zonguldak terrane is a Gondwana-derived continental microplate along the Black Sea coast in northwest Anatolia. It includes a Cadomian basement, with oceanic-and island-arc sequences, unconformably overlain by siliciclastic rocks of Ordovician to Middle Silurian age. After a period of deformation and erosion, late Lower Devonian (Emsian) quartzites and shallow-marine limestones unconformably cover Middle Silurian (Wenlock) graptolitic shales. Along several cross sections across the unconformity plane, the mineralogical characteristics of the Paleozoic sedimentary rocks in the Zonguldak terrane are studied to check whether this regional unconformity is only of epeirogenic nature or the result of a thermal event. In addition to the appearance of kaolinite in Devonian units, crystal-chemical data of illites show a sudden jump at the unconformity plane. The b cell dimension values of illites of Ordovician-Silurian units are somewhat higher than those of Devonian-Carboniferous units and show a drastic drop between the Silurian and Devonian units. The new mineralogic data indicate that the pre-Emsian rocks in the Zonguldak terrane experienced a thermodynamo event, prior to the Emsian transgression. This Caledonian-time event is also reported in east Moesian terrane but not noticed in the neighboring Istanbul-Zonguldak and in the west Moesian Balkan - Kreishte terranes. By this, it is suggested that Zonguldak and east Moesian terranes behaved independently from the Istanbul-Balkan terranes during the closure of the Rheic Ocean. They very likely docked to Laurussia during Emsian by strike-slip faults and remained thereon at its platform margin, where the Middle-Late Devonian shallow-platform conditions were followed by fluvial (lagoon and delta) conditions and deposition of coal during Late Carboniferous.


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Bozkaya, Omer; YALÇIN, HÜSEYİN; Göncüoğlu, Mehmet Cemal (2012-07-01)
The Istanbul Terrane along the Black Sea coast in NW Anatolia, is a Gondwana-derived continental microplate, comprising a well-developed Paleozoic succession. Petrographic and X-ray diffraction studies were performed on rock samples from measured sections throughout Ordovician-Carboniferous sedimentary units. Diagenetic-very low-grade metamorphic clastic (shale/mudstone, siltstone, sandstone) and calcareous rocks (limestone, dolomite) mainly contain phyllosilicates, quartz, feldspar, calcite, dolomite, hema...
Diagenesis of Cudi group formations from Dinçer-1 and south Dinçer 1 wells, se Anatolia Turkey
Kahraman Özkan, Ayşegül; Günal Türkmenoğlu, Asuman; Department of Geological Engineering (2010)
Dinçer-1 (1968) and South Dinçer-1 (1980) exploration wells are located at Şırnak Province of Southeast (SE) Anatolia. South Fields of SE Anatolia have received a significant attention after the completion of subjected wells and numerous studies have been implemented regarding this area. Many theories about the geological generation of these fields were put forward by people who studied this region.Both wells have penetrated the Arabian Plate autochthonous units. The Cudi Group, of this sequence, mainly con...
Holocene paleoenvironmental evolution of the Acıgöl paleo maar lake (Nevşehir, Central Anatolia)
Tuncer, Alaettin; Tunoğlu, Cemal ; Aydar, Erkan ; Yılmaz, İsmail Ömer; Gümüş, Burçin Aşkım ; Şen, Erdal (2019-12-01)
Acıgöl (Nevşehir, Central Anatolia) is a drained crater lake. Acıgöl maar was formed by the violent vapor explosions due to the interaction of hot rhyolitic magma with the (sub-)surface water during the latest Pleistocene. A 844 cm-deep borehole was drilled at the maar and 713 cm-thick Acıgöl Core Succession (ACS) was retrieved. The ACS is mainly composed of lower laminated and upper non-laminated mudstones (sandy, silty, and clayey) with rare organic and volcanic interlayers. Eleven ostracod taxa (Cypris p...
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Göncüoğlu, Mehmet Cemal; Sayıt, Kaan (2010-04-01)
The remnants of the Neotethyan Izmir-Ankara Ocean, the main branch of Neotethys in the eastern Mediterranean are represented by the Dagkuplu Melange Complex in Central Sakarya, NW Turkey. It comprises several blocks or tectonic slices of pillow lavas, some of which include mudstones and radiolarian cherts as intra-pillow-fillings or interlayers. In the Igdecik area, a huge basaltic block has been studied in detail Geochemical data reveal three distinct basalt types separated by sheared contacts The first of...
Geochemistry, tectono-magmatic discrimination and radiolarian ages of basic extrusives within the Izmir-Ankara Suture Belt (NW Turkey): Time constraints for the neotethyan evolution
Göncüoğlu, Mehmet Cemal; Tekin, U. Kagan (2006-06-01)
The Dagkuplu Melange in the Central Sakarya Valley represents the northernmost outcrops of the Izmir-Ankara Suture Belt in northwest Anatolia. In addition to blocks and slivers of serpentinite, gabbro, blueschist, neritic and pelagic limestones, it includes blocks of basic volcanic rocks associated with radiolarian cherts, pelagic carbonates and mudstones.
Citation Formats
O. Bozkaya, H. YALÇIN, and M. C. Göncüoğlu, “Mineralogic evidences of a mid-Paleozoic tectono-thermal event in the Zonguldak terrane, northwest Turkey: implications for the dynamics of some Gondwana-derived terranes during the closure of the Rheic Ocean,” CANADIAN JOURNAL OF EARTH SCIENCES, pp. 559–575, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31985.