April 23--Transit Day 3

Betsy Williams

		April-May Sun Mon Tue Wed Thu Fri Sat 20 21 22 23 24 25 26 27 28 29 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Today's Questions Q. What do you expect to learn from the thermal vents? (From Chinook Middle School, Lacey WA) A. Our challenge is to learn how they formed, whether they have been active for thousands of years, and how their unique chemistry supports life. If we can understand the processes involved, we may gain insights into what vent systems were like when the Earth was very young. Such knowledge may help us search for vents and life on other planets. Q. Was it hard to find the Lost City? (From Chinook Middle School, Lacey WA) A. The discovery of the Lost City was one of those rare times when you are in the right place at the right time. We did not go out to the Atlantis Massif to find the field, it was complete luck and shows that there is still much that we do not know about our oceans.

Last night the Alvin pre-dive briefings began. Blee Williams, an Alvin pilot, gathered the eight of us who have never dived before for an orientation and safety lecture. He explained that the Alvin group lives by the three S's: Safety, Sub, and Science -- in that order. Getting the pictures and samples we need for research are secondary to getting everyone back to the ship safely every day, and there are many rules and procedures to help make sure that happens. Two by two, we entered "the Ball", the titanium sphere that makes up the living space of Alvin. Just entering the submersible requires a 10-minute safety lecture.

Ben Going into Alvin

The opening on the top is a small hatch, and there are many oppor-tunities to touch something you should definitely not touch while lowering yourself down. Inside, Gavin Eppard, a Pilot-In-Training (yes, they call him a PIT) explained the basics of what to do during a dive while we crouched on the metal floor, gaping at the arrays of switches and monitors. Some more experienced divers are getting a briefing tonight.

This afternoon we had an overview science meeting at which Jeff Karson and Debbie Kelley gave presentations about our mission. Because the team is so diverse, including geologists, biologists, chemists, and Alvin

Mantle Cross Section

Argonite and Brucite

pilots, these presentations cover the basics, including terminology. Jeff opened the meeting by explaining the geologic setting of the Lost City. The cartoon on the right (from his presentation) shows how mantle peridotite can be uplifted and exposed along a detachment fault. Debbie then talked about the chemistry of the carbonate chimneys and the microbes that live on and within the towers. The scanning electron microscope (SEM) image (lower right) is from a piece of a chimney collected on previous cruise to this site. The needle-like crystals are aragonite (CaCO3) and the rounded rosettes are brucite (Mg(OH)2). More science presentations will occur during the next few days of transit.

On a lighter note, we had beautiful weather today and also a treat for dinner: pizza and soda followed by Rocky Road ice cream. It seems that there are two factions aboard ship: those who think marshmallows make anything better and those who think they just don't belong in ice cream.