|A rare fish at the vent site|
|The colours at the vent site are stunning|
At the astonishing depth of 5080 metres, in the bottom of the deepest valley, we find a carpet of bright orange mud. Such a startling contrast in colour means only one thing: even down here, the minerals falling out from the distant vent field are having a profound impact. The orange colour is the result of iron. Spewed from the hydrothermal waters at over 400°C, the iron oxidises rapidly and falls as rust onto the seabed below. The accumulations here speak of thousands of years of fall-out.
The colours here are amongst the most amazing sights: oranges and reds from the abundant iron, but also peacock hues of green, blue and purple: sure signs that copper is also in abundance. In places, green ‘stalagmites’ cling precariously to the rocky overhangs. Formed from a copper mineral called ‘atacamite’, here the copper is literally leaking out of the rock. This is an amazing sight to us as it confirms one of the hypotheses that bought us here: that the hydrothermal minerals at these depths and high temperatures will be rich in copper. Back on the ship, these rocks are indeed like peacocks: their vibrant colours attract everyone’s attentions and, for the first time, compete on an even footing with the biology for being the most photogenic.
|The science party relaxing at sunset on deck after completion of dives.|