Middle-Late Triassic radiolarian cherts from the Arkotdag m lange in northern Turkey: implications for the life span of the northern Neotethyan branch

Göncüoğlu, Mehmet Cemal
Pandolfi, Luca
Marroni, Michele
Moderately to well-preserved, relatively diverse Middle and Late Triassic radiolarian assemblages have been obtained from the chert slide-blocks within the Late Cretaceous melange of the IntraPontide Suture Zone at the Pelitoren village to the NE of Kastamonu-Arac in northern Central Anatolia. In this locality, chert slide-blocks are tectonically overlain by metamorphic sole of the serpentinized peridotites belonging to the IntraPontide ophiolites. The oldest radiolarian assemblages, with the middle Late Anisian and late Early Ladinian ages, were found in green cherts in a pebbly mud-stone. They are underlain by a larger slide-block composed of an alternation of radiolarian cherts and mudstones with late Early and early Late Carnian radiolarians. Another slide-block with cherts and mudstones between the sub-ophiolitic amphibolite and the Carnian cherts includes the late Early to early Middle Norian radiolarian assemblages. These new data reveal that the IntraPontide basin was already open during the Middle to Late Triassic time and deep enough for radiolarian cherts to deposit. Moreover, it suggests that the IntraPontide Ocean is contemporaneous with a number of inferred Paleo- and Neotethyan oceanic basins in SE Europe and NW Anatolia, which were proposed in copious tectonic models.


Late Middle Jurassic (Late Bathonian-early Callovian) radiolarian cherts from the Neotethyan Bornova flysch zone, Spil Mountains, Western Turkey
TEKİN, UĞUR KAĞAN; Göncüoğlu, Mehmet Cemal (2009-06-01)
Alternating radiolarian cherts and mudstones associated with basaltic lavas occur in a olistolith within the Late Cretaceous Bornova Flysch in W Anatolia. Cherts yielded diverse and moderately preserved, Nassellaria-dominated radiolarian faunas of late Bathonian-early Callovian age. Associated volcanic rocks are geochemically classified as remnants of oceanic seamounts. This is so far the first late Middle Jurassic age from the crust of the Neotethyan Izmir-Ankara Ocean in W Anatolia, and suggests that its ...
Early-Middle Triassic echinoderm remains from the Istranca Massif, Turkey
Hagdorn, Hans; Göncüoğlu, Mehmet Cemal (2007-01-01)
In the northwestern part of the Istranca Massif close to the Turkish-Bulgarian border, recrystallized limestones above germanotype fluvial clastics (Buntsandstein-equivalents) yielded remains of echinoderms and bivalves. The limestones are lensoidal, flaser-bedded and bioturbated, like the Holocrinus lagerstatten, which are common in the germanotype Muschelkalk. The sufficiently preserved crinoid ossicles can be assigned to genus Holocrinus, a crinoid clade that occurs worldwide in Early and Middle Triassic...
Oceanization of the northern Neotethys: Geochemical evidence from ophiolitic melange basalts within the Izmir-Ankara suture belt, NW Turkey
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...
Geological evolution of the Central Pontides
Okay, Aral; Altıner, Demir; Sunal, Gursel; Aygul, Mesut; Akdogan, Remziye; Altıner, Sevinç; Simmons, Mike (2015-10-07)
Before the Late Cretaceous opening of the Black Sea, the Central Pontides constituted part of the southern margin of Laurasia. Two features that distinguish the Central Pontides from the neighbouring Pontide regions are the presence of an extensive Lower Cretaceous submarine turbidite fan (the Cag.layan Formation) in the north, and a huge area of Jurassic-Cretaceous subduction-accretion complexes in the south. The Central Pontides comprise two terranes, the Istanbul Zone in the west and the Sakarya Zone in...
Middle Carnian Arc-Type Basalts from the Lycian Nappes, Southwestern Anatolia: Early Late Triassic Subduction in the Northern Branch of Neotethys
Sayıt, Kaan; Göncüoğlu, Mehmet Cemal (2015-11-01)
The Turunc Unit, which represents one of the tectonic slices within the Lycian Nappes in southwestern Anatolia, preserves the remnants derived from the northern branch of Neotethys. The unit includes basalts intercalated with pelagic limestones of middle Carnian age (early Late Triassic) based on the characteristic radiolarian assemblage of the Tetraporobrachia haeckeli Zone. The Turunc lavas reflect trace element signatures resembling those from subduction zones, displaying selective enrichment of Th and l...
Citation Formats
U. K. TEKİN, M. C. Göncüoğlu, L. Pandolfi, and M. Marroni, “Middle-Late Triassic radiolarian cherts from the Arkotdag m lange in northern Turkey: implications for the life span of the northern Neotethyan branch,” GEODINAMICA ACTA, pp. 305–319, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32300.