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cloudy weather
64°F (17.8°C)
Latitude: 27deg 0’ N
Longitude: 111deg 24’ W
Wind Direction: WNW
Wind Speed: 19 Knots
Sea State: 3
Swell(s) Height: 3 Feet
Sea Temperature: 64°F (17.8°C)
Barometric Pressure: 1014.8 MB
Visibility: 20 Nautical Miles

what's to eat today?
Eggs to order
Corned beef puff pastries
Cottage potatoes
Pancakes with mixed berries
Fresh fruit

“Fishmonger” clam chowder Sloppy Joes
Tuna sandwiches
Bombay rice salad
Onion rings
Salad bar

Grilled lamb chops
Jurel fresco al moho de ajo (Garlic style fresh yellowtail)
Roast Yukon gold potatoes
Pesto cous cous
Cauliflower florets
Green beans with sautéed peppers
Roast garlic
Herb foccacia bread
Oh Yeah! Bars

Don Nuzzio watches as the electrodes are lowered into the core to take chemical measurements.


Daily Update: Dive 3522
January 19, 2000
By Dr. Dan Fornari and Dr. Susan Humphris

The wind picked up overnight, but the morning dawned with another beautiful Baja sunrise. Craig Cary, Liz McCliment, and Pilot Steve Faluotico spent a full day on the seafloor taking sediment cores, collecting clams, and doing more chemical sensor and "Sipper" work at the hydrothermal vents.

Today marks the start of the second week at sea, which means it's time for another Fire & Boat Drill to practice emergency procedures. At 1015 hrs, the alarm sounded and the crew simulated a fire in the motor propulsion room. All of the scientists mustered in the main lab and waited for the crew to finish their drill.

Today’s work focused on the core samples. The scientists are trying to learn how the chemical environment within the thick seafloor sediments affects the community of microorganisms that live there. These microorganisms form colorful white, red, yellow and brown mats on the seafloor.

A key piece of equipment we are using is the Electrochemical Analyzer. This instrument is the brainchild of Don Nuzzio, the president of Analytical Instrument Systems, Inc. in Flemington, N.J. Don’s company makes sophisticated chemical analyzers that scientists use to monitor coastal waters, lakes, rivers, and now hydrothermal vents at the bottom of the ocean. The Electrochemical Analyzer has tiny chemical sensors (or electrodes) that measure oxygen, iron, sulfur and manganese concentrations at different locations around the vents. The presence of these elements determines which microorganisms live in specific places.

Before coring, the scientists in Alvin must choose a suitable site. First they search for bacterial mats on the ocean floor. Next they use the Electrochemical Analyzer to measure the chemical environment in the water directly above the mat. If they decide it is a good place to core, they stick a temperature probe into the sediment to check whether the sediment temperature is less than 100°C. Microbes are most likely to be found at these cooler temperatures. Next, they use the “Sipper” to collect water samples, which they will analyze later in the ship’s lab. Finally, they are ready to take a 30-centimeter core sample. They plunge the corer through the bacterial mat and into the sediment below. (Check out the video of coring the seafloor).

Once the cores are back on the ship, the scientists make numerous electrochemical measurements along the top five centimeters of each core. This is the part of the core that is the most critical to the microorganisms. They then slice the core into sections, trying to separate parts of the core that have different chemistries. For example, they might have one slice that contains oxygen and another slice that contains hydrogen sulfide. Before slicing, they put the core inside a bag filled with nitrogen. This prevents the chemical environment inside the core from changing due to air exposure.

The scientists then put the slices into a centrifuge. The centrifuge spins the slices at very high speeds, drawing the water out of the sediment. The microbiologists take some of the sediment to grow (or culture) any of the microbes that are present. They then use molecular techniques to determine which microbes are present. The rest of the sediment is taken back to the shore lab where scientists will identify the minerals present and look for hydrocarbons (petroleum products). Hydrocarbons are abundant in Guaymas Basin sediments. Scientists will also analyze the water that was spun off in the centrifuge for iron and sulfur compounds.

After all of the analysis is done, the scientists will couple the chemical environment data with the results of the microbiological work. They hope to learn how the chemical environment affects the types of microorganisms that survive on the ocean floor.

Dive Summary
On Bottom: 0922 hrs.
Off Bottom: 1532 hrs.
Maximum Depth: 2000m

The dive started at Rebecca’s Roost-a large sulfide structure with many ledges (or flanges). The scientists on Alvin collected “Sipper” samples and did chemical scanner profiles on the hot hydrothermal fluids discharging from the vent. Growing out of the top of one of the flanges was a small 300°C “beehive” chimney. It is called a "beehive" because it has delicate surface textures that resemble a paper wasp's nest. Steve used Alvin's manipulator to sample the “beehive” (check out the video of the “beehive” sampling). The sample broke off, but Steve was able to grab it with the manipulator and put it in the basket. He also collected some fluids with the gas-tight sampler.

Craig, Liz, and Steve then headed away from the area of the most active venting. They wanted to find and sample sediment that differed from the sediment they had been sampling over the past few days. They collected another pink spiny spider crab and four cores of mud. The mud was much different from the gas-rich sediment that they had sampled near the vents. George and the rest of the chemistry group are now analyzing the cores.

Craig, Liz and Steve also collected more clams. All in all, another successful dive.

One additional note -- Craig and Tim learned that the spiny spider crab, while fairly common in the deep ocean, has never been sampled and cataloged before. They have agreed to send the one they collected on this dive to the Smithsonian Institution in Washington, D.C, to be archived.