Geochemistry of mafic rocks of the Karakaya complex, Turkey: evidence for plume-involvement in the Palaeotethyan extensional regime during the Middle and Late Triassic

Date

2009-03-01

Author

Sayıt, Kaan
Göncüoğlu, Mehmet Cemal

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

305
views

0
downloads

The Karakaya Complex within the Early Mesozoic Cimmerian Orogeny in northern Turkey represents the remnants of the Palaeotethys. It includes slivers and/or mega-blocks of slightly metamorphic basic volcanic rocks associated with fossiliferous sediments as well as hypabyssal and intrusive rocks with basaltic-andesitic to ultramafic compositions. They display two distinct compositional groups; namely alkaline and variably tholeiitic. The alkaline basalt samples are more akin to oceanic-island basalts (OIB) with relatively enriched trace element characteristics together with strong partitioning in HREE ([La/Yb](N) = 5.8-16.2), suggesting that garnet is present as a residual phase in the source of those basalts. The variably tholeiitic samples apart from diabases display E-MORB characteristics; being relatively depleted compared to the alkaline counterparts and less fractionated REE patterns ([La/Yb](N) = 2.1-3.6). The diabases, on the other hand, are distinctively different with a significant negative Nb anomaly (Zr/Nb = 28.9-43.4) and flat REE patterns ([La/Yb](N) = 0.8-1.4), suggesting their generation above a supra-subduction zone, probably a back-arc basin. These results may suggest that a mantle plume-related magmatism associated with extensional oceanic system should have been installed within Palaeotethys during Middle-Late Triassic time, which was then incorporated into subduction-accretion prism forming the final picture, that is, "the Karakaya Complex''.

Subject Keywords

Karakaya Complex, Mantle Plume, OIB, Triassic, Palaeotethys

URI

https://hdl.handle.net/11511/32138

Journal

INTERNATIONAL JOURNAL OF EARTH SCIENCES

DOI

https://doi.org/10.1007/s00531-007-0251-6

Collections

Graduate School of Natural and Applied Sciences, Article

Suggestions

OpenMETU
Core

Geochemistry of the metavolcanic rocks from the Cangaldag Complex in the Central Pontides: implications for the Middle Jurassic arc-back-arc system in the Neotethyan Intra-Pontide Ocean Cimen, Okay; Göncüoğlu, Mehmet Cemal; Sayıt, Kaan (2016-01-01) The Cangaldag Complex in northern central Turkey is one of the main tectonic units of the Central Pontide Structural Complex that represents the remains of the poorly known Intra-Pontide branch of the Neotethys. It comprises low-grade metamorphic rocks of intrusive, extrusive, and volcaniclastic origin displaying a wide range of felsic to mafic compositions. Petrographically the complex consists of basalts-andesites-rhyodacites and tuffs with minor amount of gabbros and diabases. On the basis of geochemistr...
Geochemistry of mafic dykes from the Southeast Anatolian ophiolites, Turkey: Implications for an intra-oceanic arc-basin system Colakoglu, Ali Riza; Sayıt, Kaan; Gunay, Kurtulus; Göncüoğlu, Mehmet Cemal (2012-02-01) The Late Cretaceous-Tertiary accretionary prism in Eastern Turkey includes several ophiolitic megablocks and/or tectonic slivers (Mehmetalan, Mollatopuz and Alabayir) within a melange complex, mainly comprising harzburgite, dunite and cumulate-textured gabbro. The diabases, which are the main focus of this study, cut across the ophiolites as parallel and variably thick dyke-swarms. Geochemistry of the diabases reveals three distinct groups, including a) supra-subduction zone (SSZ) type, which is characteriz...
Geochemical characteristics of mafic lavas from the Neotethyan ophiolites in western Turkey: implications for heterogeneous source contribution during variable stages of ocean crust generation ALDANMAZ, ERCAN; Yaliniz, M. K.; GÜÇTEKİN, AYKUT; Göncüoğlu, Mehmet Cemal (2008-01-01) The Late Triassic to Late Cretaceous age mafic lavas from the Neotethyan suture zone ophiolites in western Turkey exhibit a wide diversity of geochemical signatures, indicating derivation from extremely heterogeneous mantle sources. The rocks as a whole can be divided into three broad subdivisions based on their bulk-rock geochemical characteristics: (1) mid-ocean ridge basalts (MORB) that range in composition from light rare earth element (LREE)-depleted varieties (N-MORB; (La/Sm)(N) < 1) through transitio...
Geochemistry and Petrology of the Kösedağ metavolcanic rocks Sakarya Composite Terrane Northern Turkey Berber, Faruk; Göncüoğlu, Mehmet Cemal; Sayıt, Kaan (2015-08-21) Central Pontides in Northern Turkey is a key area, comprising variably metamorphosed and deformed low-grade metavolcanic rocks. In this study we report the geochemical characteristics of the Kösedağ metavolcanics (KMV), and infer their tectonomagmatic evolution. The KMV include blastomylonitic volcanic rocks covered by the Cretaceous clastics and carbonates. The chemical composition of the KMV ranges from basalt, andesite to dacite. The evolved magma compositions reflect fractionation of plagioclase, Fe-Ti ...
Geochemistry and Zircon U-Pb Dates of Felsic-Intermediate Members of the Late Cretaceous Yuksekova Arc Basin: Constraints on the Evolution of the Bitlis-Zagros Branch of Neotethys (Elazig, E Turkey) Ural, Melek; Sayıt, Kaan; KORALAY, OSMAN ERSİN; Göncüoğlu, Mehmet Cemal (2021-08-01) During the Late Cretaceous in the Eastern Mediterranean, the northern branch of the southern Neotethys was closed by multiple northward subductions. Of these, the most northerly located subduction created the Baskil continental arc at around 82-84 Ma. The more southerly and intra-oceanic subduction, on the other hand, produced an arc-basin system, the Yuksekova Complex, as early as the late Cenomanian-early Turonian. The abundant and relatively well-studied basaltic rocks of this complex were intruded by dy...

Citation Formats

K. Sayıt and M. C. Göncüoğlu, “Geochemistry of mafic rocks of the Karakaya complex, Turkey: evidence for plume-involvement in the Palaeotethyan extensional regime during the Middle and Late Triassic,” INTERNATIONAL JOURNAL OF EARTH SCIENCES, pp. 367–385, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32138.