Comment on "Revealing the early geological history of the Istanbul Zone (Far-East Avalonia) through zircon U-Pb-Hf isotopic data" by Yılmazer et al. (2025), Precambrian research 427, 107855

Sen F.

PRECAMBRIAN RESEARCH, cilt.430, 2025 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Editöre Mektup
  • Cilt numarası: 430
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1016/j.precamres.2025.107939
  • Dergi Adı: PRECAMBRIAN RESEARCH
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Artic & Antarctic Regions, Chemical Abstracts Core, Geobase, INSPEC
  • İstanbul Üniversitesi Adresli: Hayır

Özet

Y & imath;lmazer et al. (2025) interpret a single detrital zircon U-Pb age of 530 +/- 29 Ma from the Kurtkoy Formation as evidence for an Upper Cambrian or younger depositional age. However, this interpretation merits re-evaluation in light of the relatively large analytical uncertainty (+/- 5.5 %) and the absence of corroborating biostratigraphic or sedimentological evidence. Stratigraphic relationships and multiple well-defined zircon age populations (582 +/- 5 Ma, 554 +/- 8 Ma, and 544 +/- 10 Ma) strongly support a Late Ediacaran depositional age. Additionally, the purported unconformable contact between the Kurtkoy Formation and the underlying Yellice Volcanics is not supported by field observations, which instead suggest a tectonic boundary. Provenance data also indicate derivation from the nearby Yellice Arc rather than distant sources such as the Timanide Belt. An alternative interpretation of the depositional age and provenance of the Kurtkoy Formation is proposed here, with broader implications for the tectono-stratigraphic evolution of the I(center dot)stanbul Zone.