Bursa chondrite ( L6) about 4.2 Ga &nbsp;by U- Pb (TIMS ) the oldest (3.7 Ga) age of zircon (SHRIMP) and ICP-MS data on Ir anomaly (impact) for the continental crust of the N-W part of Fennoscandian Shield (Arctic region)

Tamara Bayanova; Ersin Kaygısız; Svetlana Drogobuzhskaya; Ksenia Dokukina; Evgeniy Kunakkuzin

doi:https://doi.org/10.5194/egusphere-egu26-2328

[Back] [Session PS6.3]

EGU26-2328, updated on 13 Mar 2026

https://doi.org/10.5194/egusphere-egu26-2328

EGU General Assembly 2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

Poster | Thursday, 07 May, 14:00–15:45 (CEST), Display time Thursday, 07 May, 14:00–18:00

Hall X4, X4.145

Bursa chondrite ( L6) about 4.2 Ga by U- Pb (TIMS ) the oldest (3.7 Ga) age of zircon (SHRIMP) and ICP-MS data on Ir anomaly (impact) for the continental crust of the N-W part of Fennoscandian Shield (Arctic region)

Tamara Bayanova¹, Ersin Kaygısız², Svetlana Drogobuzhskaya³, Ksenia Dokukina⁴, and Evgeniy Kunakkuzin¹

Tamara Bayanova et al.

¹Geological Institute, Kola Science Centre, Russian Academy of Sciences, Apatity, Russia
²Fatih Sultan Mehmet Vakif University, Research Center for the Conservation of Cultural Property of Foundation, Istanbul, Türkiye
³Tananaev Institute of Chemistry and Technology of Rare Elements and Mineral Raw Materials KSC RAS, Apatity, Russia
⁴Geological Institute of RAS, Moscow, Russia

First-time petrological and mineral-chemical studies of L6 chondrites from Bursa (Turkey) were done, and the conditions of shock metamorphism were justified. A new age of the zircon-reidite was determined at 4.2 Ga (U-Pb (TIMS)).

Gray gneisses, TTG, enderbate rocks, and amphibolites from Murmansk and Central Kola megablocks of the N-W part of the Fennoscandian Shield were dated using SHRIMP and U-Pb (TIMS) on zircon, with ages ranging 3.7-3.2 Ga.

Protoliths of country rocks, based on Sm-Nd data, reflect TDM values 3.0 to 3.5 Ga, with ɛNd values ranging from +2 to -3.

Concentrations of PGE and Ir anomalies were studied for the basement rocks of the continental crust using ICP-MS, reflecting an extraterrestrial (impact) contribution during the early formation stages of the two megablocks of the N-W part of the Fennoscandian Shield.

Additionally, the basement rocks show high concentrations of ore metals (ICP-MS data) such as Fe, Pt, Pd, Ni and other elements unusual for Earth rocks (Koeberl et.al, 2024; Treatise on Geochemistry, 2003; Van Kranendonk et.al, 2019).

This research was carried out in accordance with the research topics outlined in Scientific Research Contracts FMEZ-2024-0004. Many thanks to A.N. Larionov for the U-Pb (SHRIMP) analysis. Devoted to memory of the outstanding geochemistry Derald Wasserbourg from USA for artificial spike 205 Pb for U-Pb (TIMS) measurements single grains baddeleyite and zircon.

How to cite: Bayanova, T., Kaygısız, E., Drogobuzhskaya, S., Dokukina, K., and Kunakkuzin, E.: Bursa chondrite ( L6) about 4.2 Ga by U- Pb (TIMS ) the oldest (3.7 Ga) age of zircon (SHRIMP) and ICP-MS data on Ir anomaly (impact) for the continental crust of the N-W part of Fennoscandian Shield (Arctic region), EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2328, https://doi.org/10.5194/egusphere-egu26-2328, 2026.