Juxtaposition of Triassic and Late Cretaceous Blueschists in NW Türkiye: Implications for Neo-Tethyan Evolution
Tectonics, cilt.45, sa.7, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 45 Sayı: 7
- Basım Tarihi: 2026
- Doi Numarası: 10.1029/2026tc009417
- Dergi Adı: Tectonics
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, Environment Index, Geobase, INSPEC, Natural Science Collection (ProQuest), Earth, Atmospheric, & Aquatic Science Collection (ProQuest)
- Anahtar Kelimeler: Blueschist, Neo-Tethys, Paleo-Tethys, subduction erosion, Tavşanlı zone
- Karadeniz Teknik Üniversitesi Adresli: Evet
Özet
Subduction advance or retreat results in an erosional or accretional plate boundary, and strong orogen-parallel heterogeneity in large suture zones, but their identification of these processes is challenging. Blueschist is a proxy that can archive these tectonic processes in ancient subduction zones. Within NW Türkiye, the Tavşanlı zone preserves blueschist-facies rocks, and documents a succession of subduction events that preceded the closure of the Neo-Tethys Ocean. Here, we report for the first time the occurrence of Triassic blueschist blocks within the Late Cretaceous Tavşanlı zone. These blueschists and marbles have abundant HP minerals such as winchite, jadeite, and lawsonite, and yield zircon U-Pb age at ca. 228 Ma, resembling the Karakaya HP metamorphic rocks of the overlying Eurasian plate. The available block-matrix relationships record strong later deformation, but do not preserve the diagnostic textures required to determine whether the Triassic rocks were incorporated into the younger complex by tectonic or sedimentary processes. Regionally, the extensive low-angle geometry of the İzmir-Ankara-Erzincan suture, the scarcity of Jurassic-Early Cretaceous arc and ophiolitic remnants, the landward migration of the magmatic arc front, and provenance links between the Tavşanlı and Sakarya zones, are compatible with significant forearc removal during Neo-Tethys evolution. In this context, the Triassic HP rocks may have been either redeposited into trench-fill deposits and resubducted, or tectonically entrained along the erosive plate interface and accreted downdip. These results highlight the importance of multi-stage tectonic reworking in assembling age-disparate HP terranes along the Tethyan suture system.