Pedogenic and palaeoclimatic evidence from an Eemian calcrete in north‐western Sardinia (Italy)

Abstract

A multidisciplinary approach was followed to study the pedogenic and palaeoclimatic information preserved in a buried palaeosol belonging to a Late Quaternary succession located along the bay of Alghero (north‐western Sardinia). The bay is dominated by a 5‐km long sandy beach‐ridge system backing an N‐S oriented lagoon system (Calich). The succession studied is characterized by basal shallow marine deposits, followed by clayey lagoon sediments and colluvial strata and capped by a relatively thick aeolianite. The research was based on pedological and sedimentological analyses, supported by optically stimulated luminescence (OSL) dating and by an in‐depth micro‐morphological study. Three main climatic pulses were highlighted during the Eemian. A wet period, with intense carbonate leaching occurred at the very beginning of the Eemian interglacial followed by very dry climatic conditions. This dry phase was long and arid enough to allow the formation of a thick calcrete hardpan, a typical feature of semi‐arid environments. The hardpan is dated at about 120 ka (kilo annum) and this dry event is tentatively associated with the late Eemian arid pulse (LEAP). The last phase of the Eemian recorded the restoration of a wetter climate. Finally, the succession indicated that even in a cooler environment, the central Mediterranean most probably maintained temperate conditions at least until the end of the MIS 5c (about 95 ka; early Würm).

The role of beach ridges, spits, or barriers in understanding marine terraces processes on loose or semiconsolidated substrates: Insights from the givoni of the Gulf of Taranto (southern Italy)

“…This conclusion is consistent with the findings presented by several authors regarding precipitation in the Mediterranean area during MIS 5. This period was generally wet (Bar-Matthews, Ayalon, Gilmou, Matthews, & Hawkesworth, 2003;Hodge et al, 2008) or presented alternating wet and dry phases (Bardají et al, 2009;Mauz, Fanelli, Elmejdoub, & Barbieri, 2012;Zucca et al, 2014).…”

Upper Pleistocene tectonics in western Sardinia (Italy): Insights from the Sinis peninsula structural high

“…A relatively thick late Quaternary succession dominated by an alternating shallow marine and alluvial/aeolian deposits extensively crops out along the coast of Sardinia (West Mediterranean; Andreucci, Clemmensen, & Pascucci, ; Andreucci et al, ; Andreucci, Sechi, Buylaert, Sanna, & Pascucci, , Carboni, Lecca, Hillaire‐Marcel, & Ghaleb, ; Coltorti, Pieruccini, Montagna, & Zorzi, ; Sechi, Andreucci, & Pascucci, ; Zucca, Sechi, et al, ; Zucca et al, ; Figure ). The presence of Marine Isotopic Stage 5e (MIS5e) marine sediments close to the mean global eustatic location of around 6 m above present sea level (a.p.s.l.)…”

Post-IR IRSL 290 dating of K-rich feldspar sand grains in a wind-dominated system on Sardinia

“…The embayment is dominated by N-S oriented 5 km long sandy coastal barrier system delimiting a lagoon named Calick (Fig. 1E, study area 3; Manca et al, 2013;Zucca et al, 2014). The dune system cropping out on the study area has a maximum thickness of 10 m and was human stabilized by plantation during the 1950s.…”