PRAEG , D.

Here we present a detailed description of different geomorphic features to complement the Maps of Geohazard Features of the Ionian Calabrian Margin produced by the Magic project (Marine Geohazard along Italian Coasts). Some of the most striking features we imaged are sources of widespread and recurrent geohazards. These include multiple coastal...

The stability of methane hydrates on continental margins worldwide is sensitive to changes in temperature and pressure conditions. It has been shown how gradual increases in bottom water temperatures due to ocean warming over post-glacial timescales can destabilize shallow oceanic hydrate deposits, causing their dissociation and gas release...

The Amazon continental shelf hosted one of the world's largest mixed carbonate-siliciclastic platforms from the late Paleocene onwards - the Amapá carbonates. The platform architecture, however, remains poorly understood and causes and timing of the cessation of carbonate deposition are still controversial. Here we present a stratigraphic...

Voluminous mass-transport deposits (MTD) have been identified on seismic profiles across the central Nile Deep-Sea Fan (NDSF). The youngest MTDs are buried under 30-100 m of well-stratified slope deposits that, in water depths of 1,800-2,600 m, are characterized by undulating reflectors correlated with slope-parallel seabed ridges and troughs....

The central Nile Deep-Sea Fan contains a broad area of seabed destabilisation in association with fluid seepage: slope-parallel sediment undulations are associated with multibeam high-backscatter patches (HBPs) related to authigenic carbonates. During the 2011 APINIL campaign, a deep-towed sidescan and profiling system (SAR) was used to acquire...

Gas hydrates are ice-like compounds of water and volatiles (mainly methane) that are stable in deep-sea sediments due to high pressures and low temperatures. Changes in oceanographic conditions that reduce their stability field (e.g. sea level lowering, bottom water warming) have been suggested to trigger continental slope failures. The Amazon...

Oceanography, v. 22, n. 1, p. 92-109, 2009

On the central Nile deep-sea fan, stratified sediments overlying mass-transport deposits (MTDs) are deformed into slope-parallel seabed undulations associated with fluid seepage. The western part of this system, in water depths of 1,950-2,250 m, is examined using multi-frequency data from hull-mounted and deep-towed swath/profiling systems....