Submarine Geomorphology of the Southwestern Sardinian Continental Shelf (Mediterranean Sea): Insights into the Last Glacial Maximum Sea-Level Changes and Related Environments

Abstract

During the lowstand sea-level phase of the Last Glacial Maximum (LGM), a large part of the current Mediterranean continental shelf emerged. Erosional and depositional processes shaped the coastal strips, while inland areas were affected by aeolian and fluvial processes. Evidence of both the lowstand phase and the subsequent phases of eustatic sea level rise can be observed on the continental shelf of Sardinia (Italy), including submerged palaeo-shorelines and landforms, and indicators of relict coastal palaeo-environments. This paper shows the results of a high-resolution survey on the continental shelf off San Pietro Island (southwestern Sardinia). Multisensor and multiscale data—obtained by means of seismic sparker, sub-bottom profiler chirp, multibeam, side scan sonar, diving, and uncrewed aerial vehicles—made it possible to reconstruct the morphological features shaped during the LGM at depths between 125 and 135 m. In particular, tectonic controlled palaeo-cliffs affected by landslides, the mouth of a deep palaeo-valley fossilized by marine sediments and a palaeo-lagoon containing a peri-littoral thanatocenosis (18,983 ± 268 cal BP) were detected. The Younger Dryas palaeo-shorelines were reconstructed, highlighted by a very well preserved beachrock. The coastal paleo-landscape with lagoon-barrier systems and retro-littoral dunes frequented by the Mesolithic populations was reconstructed.

Landscapes and Landforms of Terrestrial and Marine Areas: A Way Forward

“…The outputs of research on Late Quaternary landscape changes are presented, with different approaches, in a number of papers of this Special Issue. Mattei et al [17] supported their research by means of archaeological markers; De Gioiosa et al [24], Deiana et al [27], and Savini et al [26] analyzed terrestrial and marine landforms to reconstruct past sea-level oscillations and paleolandscapes; and Novack et al [25] took advantage of the acoustic characterization of stratigraphic records.…”

“…Deiana et al [27] analyzed a large amount of multisensor data (seismic data, MBES and SSS data, dives, and UAV data) from the continental shelf off San Pietro Island (Sardinia, Italy) to reconstruct the geomorphological evolution of the area during the LGM. The authors outlined the complexity of a variety of coastal paleolandscapes, which also hosted Mesolithic population.…”

Environmental Status and Geomorphological Characterisation of Seven Black Coral Forests on the Sardinian Continental Shelf (NW Mediterranean Sea)

“…The eastern coast of Sardinia is characterized by a continental shelf with a narrow extension and a steep slope, incised by numerous submarine canyons [41]. The seventh site, known as Carloforte Shoal (hereafter Carloforte) [19], is located off the coast of the southwestern sector of the island, and it is characterised by the presence of a wide continental shelf, showing extensive areas of outcropping and suboutcropping of rocky volcanic substrates [42] (Figure 1). Anthropogenic pressures, mainly related to fishing activities and litter disposal along the Sardinian continental shelf, especially within submarine canyons, have been reported in numerous studies [43][44][45].…”

Evolution of Deep-Seated Gravitational Slope Deformations in Relation with Uplift and Fluvial Capture Processes in Central Eastern Sardinia (Italy)

“…To analyze the DGSDs at the local scale, we used high-resolution digital elevation models (DEMs) acquired via structure from motion from a UAV-DF [8,[103][104][105][106].…”