When the megacore tube comes up, it is not in layers. It is a solid core of sediment with some water on the top. The team then pours the water through a very fine seive that allows the water to flow out but traps any organisms that might be in there. Then the slice off the top 10cm of sediment in segments and analyze each segment for organisms to see who is living down there. There were different types of worms. Sometimes in the water there would be jelly fish. Those were really beautiful - medusa jellies, I believe they were called.
I understand. Thanks for clearing that up. Hope to hear from you!
-Shannon from John Wood's period 6 class