Project description

Competition: PN-III-ID-PCE-2021 – Exploratory projects, UEFISCDI

Project code: PN-III-P4-ID-PCE-2021-0901

Project number: PCE 50 din 31/05/2022

Project duration: 31 months (0.2.06.2022-31.12.2024)

Research area: Geology, tectonics, volcanology, sedimentology

Project Director: Relu-Dumitru ROBAN

Institution: University of Bucharest, Faculty of Geology and Geophysics, Nicolae Bălcescu 1, Bucharest

Constraining the nature and evolution of sedimentary basins preserved as tectonic fragments in suture zones is hindered by the insufficient lithological record surviving their closure. The Ceahlău –Severin Suture (CSS) represents a vast but poorly characterized sedimentary environment dominated by deep-sea J₃-K₁ sediments, which host mafic and ultramafic fragments at various stratigraphic levels, better preserved in the southwest of CSS previously interpreted as remnants of strongly dismembered ophiolites of oceanic origin. Elsewhere in CSS, turbidites are far more abundant, whereas basaltic blocks with a mid-ocean ridge or island magmatic arc affinity occur sparsely. We intend to address two fundamental questions. (1) How much crust/lithosphere extension is required to explain the properties of mafic rocks or sediments and what was the tectonic environment forming such basin? (2) How did the sedimentary filling process progress across the basin, and what did the detrital sources contribute to the deposits? We plan to (a) evaluate the trace element, Sm-Nd, and U-Pb isotopic characteristics of CSS mafic fragments, which offer valuable clues about their petrologic and tectonic conditions as well as the age of formation, and (b) reconstruct the routing sedimentary systems by facies modeling, provenance analysis of heavy minerals and lithoclasts, and zircon U-Pb geochronology.