Making Dive Plans

Today I wanted to spend a little time talking about the planning that goes into each ALVIN dive. At 7:00 PM the previous evening, a post-dive evaluation and a pre-dive plan are presented. The dive evaluation shown above was from Sunday, April 2. Before the dive, the locations to be visited are put out in a dive plan that includes what is to be sampled and what biological/geological is to be performed.

The entire area where the research is taking place is on top of the East Pacific Rise and is no more than about 3 nautical miles long. Things have to be well planned out, since the ALVIN motors along at a brisk 2 nautical miles/hour at top speed!

It takes 1 1/2 hours to reach the bottom and then the fun begins. Imagine starting at Cape Henlopen High School in Lewes and driving south to Rehoboth - the entire area we are working in is an area about the size of the area from route 1 going into Rehoboth to the boardwalk. Once we get there, we only have a couple of hours near the bottom so we have to have a great search plan!

As you can see from the dive, #4879 in the total history of ALVIN dives dating back to 1964, three major water samples were obtained (in the titanium major samplers that I am responsible for cleaning and reassembling after each dive). Also collected were mat material (microbial) on a sulfide rock and a slurp sample (fluid and material) collected over the top of Riftia. The different locations are highlighted in yellow on the map. The dives start at 8:00 AM every day.

All of the material is collected on the front end of ALVIN using the incredible robotic arms. Items are stored in baskets or containers and readily taken off when it comes back up at 5:00 PM. Then the fun begins. We usually work until well after midnight - getting stuff ready for tomorrow's dive and analyzing samples.

On a lighter note...............

I am not sure how they managed to find me, but it seems some laughing gulls located our ship at sea and have made it there home. Great. French fry thieves from our hometown have followed me to the Pacific! The ship crew said that having them so far out to sea is very rare.