Last glacial maximum deglaciation of the Southern Velebit Mt. (Croatia): insights from cosmogenic 36Cl dating of Rujanska Kosa

Abstract

Although several types of glacial landforms and deposits were described from different parts of the Croatian Dinarides, up to date there are no quantitative glacial chronological data. Here we present the first cosmogenic 36 Cl glacial chronology from the Southern Velebit Mt. from a moraine complex known as the Rujanska Kosa. We sampled four limestone boulders and used 20 mm ka −1 erosion corrected ages, as the study area is composed of well-karstified carbonate deposits and located in one of the highest precipitation regions of Europe. The inner Rujanska Kosa ridge yielded an age of 20.7 ± 2.2 ka for the retreat of glaciers in that part of Velebit Mt. A slightly older age was measured from the outer ridge on the left-lateral part of the Rujanska Kosa, which dates back to 22.7 ± 2.7 ka ago. Whilst the ages between inner and outer ridges overlap within error, we can place an age difference between the two moraines to be between 0 and 6.9 ka, supported by the geomorphic evidence that the latter is older. Although we could not perform any geomorphological work higher up in the Rujno paleoice field due to the remnant minefields, our results may indicate a Late Pleistocene (i.e. la st glacial maximum) retreat of ice from the Southern Velebit Mt. Despite the small number of valid samples, acquired age data on glacial landforms in Southern Velebit Mt. are in accordance with ages from several other Mediterranean mountain ranges.

Speleothem Records of the Hydroclimate Variability throughout the Last Glacial Cycle from Manita peć Cave (Velebit Mountain, Croatia)

“…Namely, glacial periods left some landmarks in the surroundings of MP, such as LGM terminal moraine in Rujanska kosa (6 km NW from MP cave) at the present altitude of 920 m a.s.l. [90], and tills reaching a minimum altitude of 800 m a.s.l. [91].…”

Terrestrial cosmogenic 10Be dating of the Última Esperanza ice lobe moraines (52°S, Patagonia) indicates the global Last Glacial Maximum (LGM) extent was half of the local LGM

“…On the other hand, several studies in the northern hemisphere indicate that gLGM was synchronous in the Alps (Monegato et al, 2017;Seguinot et al, 2018) and most of the Mediterranean region (Hughes and Wood ard, 2017;iner, 2015, 2017). For instance, numerous examples from the eastern Mediterranean (e.g., Sar ka a et al, 2014; K se et al, 2019), eastern Black Sea Mountains of Turkey (Akçar et al, 2007(Akçar et al, , 2008, central Anatolia (Sar ka a et al, 2009;Ak ar et al, 2014), the Caucasus (Dede et al, 2017), Greece (Leontaritis et al, 2020), Dinarids (Çiner et al, 2019Zebre et al, 2019Zebre et al, , 2021Sar ka a et al, 2020), and Corsica (Kuhlemann et al, 2008) show that most of the glaciers were in tune with gLGM and reached their maximum extents in MIS 2, with temperatures dropping between 8 to 11 o C depending on the regions (e.g., Sar ka a et al, 2008Sar ka a et al, , 2009Hughes et al, 2013;Ünal-mer et al, 2015;Canda et al, 2020). Ho e er, t o essential e ceptions come from the Iberian Peninsula and Morocco, where the maximum ice extents were reached between c. 30 and c. 60 ka (Oliva et al, 2019), and c. 50 ka, (Hughes et al, 2018(Hughes et al, , 2020 from MIS 5 to 3, respectively.…”

Changes in Cave Sedimentation Mechanisms During the Late Quaternary: An Example From the Lower Cerovačka Cave, Croatia

“…The retreat of mountain glaciers in the southern Velebit Mt. is therefore dated roughly around 20.7-22.7 ka ago (Sarıkaya et al, 2020). Even so, there is no data about glacial chronology and processes in the very close vicinity of LCC.…”