Quaternary to recent uplift rates of salt diapirs in the Romanian Carpathians determined from radiocarbon dating and PSInSAR data

Abstract

Understanding the past and present-day dynamics of salt structures is critical due to their scientific significance and societal and economic implications. Past and present salt movement can trigger hazards like sinkholes and landslides, posing risks to inhabited areas and industries such as mining, hydrocarbon extraction, and energy storage. Moreover, there is a considerable data gap regarding uplift rates of salt diapirs in humid continental climates. In this study, we investigate the relative uplift rates of the Manzalesti salt diapir, one of Europe’s largest rocksalt outcrops. We combine radiocarbon dating of vegetal fragments in sediment-filled dissolution notches (paleo-river terraces) and detailed vertical offsets extracted from digital outcrop models to calculate relative rock uplift rates. The results reveal relative salt uplift rates of 10.5 ± 0.8 and 29.8 ± 4.2 mm/year over the past ~ 720 years. We also compared these results against recent PSInSAR-derived velocities that confirm average relative vertical rates of 10 mm/year, peaking at 55 mm/year, filling a key data gap for uplift rates of salt diapirs in humid continental climates.