Morphobathymetry in the Bay of Naples
5
160 m
nw
se
5007 subbottom Chirp line
500 m
Fig.5. Subbottom chirp profile showing the enigmatic "Bacarozzi" facies: their lithology consists of shales with intercalated mid
to coarse volcanogenic sands and pumice horizons
by sediments. These morphologic highs, never
previously mentioned and now under investigation, have been sampled by coring and consist of
shaley mounds, with poorly sorted mid to coarse
volcanogenic sand and thick pumice levels.
Offshore the Sarno river mouth, at the southeastern corner of the bay, a typical estuarine sedimentation is present, producing a thick
Holocene wedge; creep movements at the sea bottom, probably controlled by horizons with high
contents of organic matter, involve Holocene sediments above a sharp surface of separation, which
may correspond to the last maximum flooding
surface (Capotondi et al. 1994), formed 5000-6000
years ago (Fig. 6). In the area offshore of Sorrento
- Punta Campanella the Holocene wedge tapers
towards the SW and the Sub bottom Chirp proftles show the occurrence of coastal regressive
sands covered by a thin Holocene drape, sometimes cropping out at the sea bottom as relic
sandy ridges.
The continental shelf south of the Punta
Campanella-Capri alignment (in the Salerno
Gulf) has not been affected by significant vertical
movements from the Se isotopic sub-stage
(Cinque and Romano 1990) and glacio-eustatic
sea level fluctuations represent the main factors
controlling the sea-bottom morpho-evolution.
On the contrary, subsidence occurred north of
this alignment, at the shelf margin, since evidence of subaerial erosion is found at depths of
140-150 m. Algal patch reefs, coastal dunes as well
as submerged depositional terraces (Budillon et
al. in press), often characterise this area and seem
to be related to the last glacio-eustatic sea level
rise.
The erosion and the transport of sediments
in the bay of Naples are chiefly driven by the
Dohrn and Magnaghi canyons, which engrave
the continental slope and shelf and expose hundred of metres of a Middle-Late Pleistocene prograding wedge made of clastic and volcanic
deposits (Fig. 7). A major morphostructural high
("Banco di Bocca Grande". also called "Banco di
Fuori") separates the two canyons and presumably is formed by a Mesozoic carbonate block
which resulted from the regional uplift and tilting of the acoustic basement. The width of the
5
160 m
nw
se
5007 subbottom Chirp line
500 m
Fig.5. Subbottom chirp profile showing the enigmatic "Bacarozzi" facies: their lithology consists of shales with intercalated mid
to coarse volcanogenic sands and pumice horizons
by sediments. These morphologic highs, never
previously mentioned and now under investigation, have been sampled by coring and consist of
shaley mounds, with poorly sorted mid to coarse
volcanogenic sand and thick pumice levels.
Offshore the Sarno river mouth, at the southeastern corner of the bay, a typical estuarine sedimentation is present, producing a thick
Holocene wedge; creep movements at the sea bottom, probably controlled by horizons with high
contents of organic matter, involve Holocene sediments above a sharp surface of separation, which
may correspond to the last maximum flooding
surface (Capotondi et al. 1994), formed 5000-6000
years ago (Fig. 6). In the area offshore of Sorrento
- Punta Campanella the Holocene wedge tapers
towards the SW and the Sub bottom Chirp proftles show the occurrence of coastal regressive
sands covered by a thin Holocene drape, sometimes cropping out at the sea bottom as relic
sandy ridges.
The continental shelf south of the Punta
Campanella-Capri alignment (in the Salerno
Gulf) has not been affected by significant vertical
movements from the Se isotopic sub-stage
(Cinque and Romano 1990) and glacio-eustatic
sea level fluctuations represent the main factors
controlling the sea-bottom morpho-evolution.
On the contrary, subsidence occurred north of
this alignment, at the shelf margin, since evidence of subaerial erosion is found at depths of
140-150 m. Algal patch reefs, coastal dunes as well
as submerged depositional terraces (Budillon et
al. in press), often characterise this area and seem
to be related to the last glacio-eustatic sea level
rise.
The erosion and the transport of sediments
in the bay of Naples are chiefly driven by the
Dohrn and Magnaghi canyons, which engrave
the continental slope and shelf and expose hundred of metres of a Middle-Late Pleistocene prograding wedge made of clastic and volcanic
deposits (Fig. 7). A major morphostructural high
("Banco di Bocca Grande". also called "Banco di
Fuori") separates the two canyons and presumably is formed by a Mesozoic carbonate block
which resulted from the regional uplift and tilting of the acoustic basement. The width of the