SEABED SAMPLING AND CORE LOGGING

The sea bottom samples were collected with 2.3 Ton gravity corer (Fig.15), the ISMAR's Mod.SW-104 water/sediment corer [Magagnoli A. and Mengoli M. (1995)] (Fig.16) and a 60L Van-Veen grab (Fig.17).

The sample locations are shown in Figg.7,9, 10 and 11 and are reported on Tab.5

Some of the cores were opened and described. All the cores were analyzed for magnetic suceptibility (2cm) using the ISMAR's automatic logger SAAS-01 by a Bartington loop sensor [Masini L. (2001)].

The volume magnetic susceptibility $\chi$ measures the capability of the material to become magnetized and to produce a noise in the inducing magnetic field, and can be used for stratigraphic correlations between cores and in the frequency analyses of temporal series to detect sedimentary cycles. Knowing $\chi$ (adimensional) and density, is it possible to determine the mass susceptibility. Minerals could be

• diamagnetic ($\chi$ $<<$ 0),
• paramagnetic ($\chi$ $>>$ 0) e.g. iron and nickel,
• ironmagnetic ($\chi$ $>>>>$ 0) e.g. (a) iron oxides, like magnetite, hematite, ilmenite, maglemite, (b) iron hydroxides like limonite and goethite, and (c) sulfurs, such as pyrite.

The obtained $\chi$ data were corrected for the loop sensor diameter (10 cm or 12,5 cm) and the sediment thickness, cleaned, filtered and plotted against core depth.

The grabs and two core-catcher were washed, sieved and described.

figure

Figure 15: 2.3 T gravity corer.

figure

Figure 16: SW-104 water/sediment corer.

figure

Figure 17: Sediments recovered with the 60L. grab.

Table 5: Cruise MARM05: location of the sediment samples.

STATION	TYPE	DATE	TIME	LON	LAT
SA-101	SW104	2005-09-13	05:46:55	26:13.68152	40:26.04119
SA-102	COR2	2005-09-13	06:56:52	26:13.69103	40:26.04936
SA-103	SW104	2005-09-13	08:17:33	26:13.67555	40:26.03650
PI-104	COR2	2005-09-16	06:21:49	29:09.54222	40:49.36678
PI-105	COR2	2005-09-16	07:04:32	29:09.54888	40:49.37142
PI-106	COR2	2005-09-16	08:02:38	29:09.55057	40:49.37111
PI-107	COR2	2005-09-16	11:29:59	28:57.92607	40:53.38996
PI-108	COR2	2005-09-16	12:13:49	28:57.93107	40:53.39460
PI-109	COR2	2005-09-16	13:07:02	28:58.29240	40:51.85500
PI-110	COR2	2005-09-16	14:15:47	29:01.42309	40:52.84784
IZ-111	SW104	2005-09-19	08:05:12	29:40.99199	40:43.77069
IZ-112	SW104	2005-09-19	08:48:28	29:41.01076	40:43.78409
IZ-113	SW104	2005-09-19	10:39:12	29:40.99589	40:43.77682
IZ-114	COR2	2005-09-19	11:41:50	29:41.00798	40:43.77287
IZ-115	COR2	2005-09-19	13:17:13	29:40.13402	40:43.47816
IZ-116	COR2	2005-09-19	14:09:59	29:40.76140	40:45.63010
01	GRA	2005-09-19	20:25:46	29:36.93581	40:42.08339
02	GRA	2005-09-19	21:46:00	29:27.47141	40:43.83069
03	GRA	2005-09-19	22:03:32	29:27.46081	40:43.83149
04	GRA	2005-09-19	22:35:25	29:27.46081	40:43.83149
05	GRA	2005-09-19	22:54:16	29:27.53270	40:43.85649
06	GRA	2005-09-19	23:26:32	29:27.33632	40:43.80858
07	GRA	2005-09-20	00:15:22	29:27.00764	40:43.73295
IZ-117	COR2	2005-09-20	07:41:06	29:42.18165	40:44.99639
IZ-118	COR2	2005-09-20	08:42:56	29:43.30675	40:43.36072
IZ-119	COR2	2005-09-20	10:53:08	29:40.98832	40:43.77744
IZ-120	COR2	2005-09-20	13:32:38	29:29.17731	40:45.90078
IZ-121	COR2	2005-09-20	14:10:05	29:29.18850	40:45.89901
IZ-122	COR2	2005-09-20	15:07:26	29:24.25779	40:44.75079
GE-123	COR2	2005-09-24	06:15:21	29:01.98169	40:23.82868
GE-124	COR2	2005-09-24	06:59:14	29:01.99450	40:23.82587
GE-125	COR2	2005-09-24	07:52:23	29:01.67126	40:24.94506
GE-126	COR2	2005-09-24	08:33:37	29:01.65890	40:24.95295
SA-127	COR2	2005-09-29	05:49:16	26:10.34994	40:23.85527
SA-128	COR2	2005-09-29	10:49:58	26:05.28425	40:26.56273