Shallow geophysics of the Asinara Island Marine Reserve Area (NW Sardinia, Italy)

Abstract

We present a high-resolution swath bathymetric and backscatter map of the entire sector of the Marine Reserve Area (MRA) of the Asinara Island, along with a geological and sediment thickness map derived from the interpretation of a large set of high-resolution seismic profiles, and an airborne-derived hyperspectral image of the Asinara Island. Acquired data show that most of the eastern marine sector of the Asinara Island is characterized by quite gentle bathymetric gradients, whereas the western coastline appears to be very indented, with an articulated and rough morphology of the seafloor, which deepens sharply towards the open sea. The maps presented in this study at the 1:50.000 scale do not only provide the first, high-resolution bathymetry of the MRA of the Asinara Island but also may furnish the base for the creation of a benthic habitat map and a more comprehensive maritime spatial planning of this protected area.

Sea Floor Characterization by Multiples’ Amplitudes in Monochannel Surveys

“…Figure 7 shows the recording geometry, with towed source and receiver divided by a gap of about 1 m, and a distance from the GPS positioning system of about 3 m. Figure 8 shows parts of the recording system, i.e., the energy source (top) and the Boomer plate (bottom). The data were acquired by OGS (Italian National Institute of Oceanography and Experimental Geophysics) in the framework of a survey committed by the Asinara Island National Park [37]. One of the objectives was to monitor the occurrence and distribution of Posidonia Oceanica, an endemic seagrass of the Mediterranean Sea that provides a good habitat for fish.…”

“…In the area studied, the seafloor consists of coarse-to-fine sediments, including marine and eolian sandstones. There are also some paleo-fluvial valleys with fluvial conglomerates and gravel sands [37,38].…”