CTD AND WATER SAMPLING

CTD casts and water sampling were taken throughout the surveyed area, aiming to detect physical or geochemical anomalies around the volcanic edifice. Data were collected by a Mod. 911Plus SBE profiling system with a 12 bottle water sampling carousel (Fig.9). The position of the CTD stations are reported in Table in Appendix 6.1 and can be viewed in Fig.19 and in Fig.3, respectively. Table 8 in Appendix 6.1 shows the data for the bottles fired for water sampling on the upcast during CTD stations. The water samples were taken at the depths of 1m and 30-50m above the bottom, in addition to some other 'standard' water depths.

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Figure 9: The rosette of R/V Universitatis .

The 911Plus probe was also towed at aproximate depths 100m above the bottom on western and eastern flanks and over the top of the volcanic edifice by using the ship's 3000m coaxial tow-cable and a twin-wing depressor normally used for high speed tow of seismic guns (see Fig.10). After having calculated the probe position in the water column, using ship's coordinates, layback cable and sensor's depth, the data were used to produce contour maps of selected parameters. Raw data were acquired and processed by SBE's SEASAVE AND SBEdataProcessing software.

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Figure 10: SBE911 CTD tow system ready to go.