Today we have been working our way along our second dive track. We are able to estimate the age of rocks on the video by the amount of sediment cover they have- the thicker the sediment, the older the rocks. One of the main reasons for doing this dive was that it would cover an area of what looked like bright, and therefore young, sheet flows on the TOBI data. As we are investigating the evolution of AVRs it would be very interesting to find extremely young lavas as they would show us which section of the ridge is currently active. Unfortunately all we have seen so far are well sedimented, old pillows.
The other reason for this track was that it would cover the area Bram has pinpointed using light scatter that may contain his hydrothermal vent. There are a number of signs that you may be near a hydrothermal vent, including an increase in water temperature and the amount and diversity of biology. Unfortunately the CTD (conductivity, temperature, depth monitor) on Isis is currently not functioning correctly, so we are unable to measure the water temperature, but we are still hoping we may be able to locate it. Check back tomorrow to see if we do!
A framegrab from the Isis video showing a haystack formed of tubular pillows.