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I'm a geologist who drove for a dozen times to explore submarine volcanoes

Looking at the night sky as a child and wondering what was out there, it was my career journey that involves diving in a cramped underwater boat in the darkness of the deep sea to see what's there.

When I was 15, I discovered I was too big to fit in those little early space capsules as an astronaut. My focus shifted to the interior, thanks to Jacques Cousteau's documentaries, detailed charts of the sea bottom and historic dives to the deepest parts of the ocean in submarines.

At college I got to know the wonders of geology and how sea bottom expansion was one of the keys to understanding the theory of the board that is developing. I was hooked.

After acquiring a PhD, my colleague from the city school Dan Fornari linked me with the National Oceanic and Atmospheric Scientists who used HOV Alvin to study the geology Rifat Galapagos – a reef spreading deep sea hydrothermal openings and animal communities for the first time discovered in the late 1970s -them. They needed a "hard-rock" geologist with marine geology to work with them – and I was thrilled to have joined in their expedition that left Acapulco. The Tectonic event on the board almost prevented me from joining a cruise when the earthquake in Mexico City in 1985 delayed my flight for hours.

My first Alvin dive into an active volcanic cleft was almost without description: a scary, exciting, fascinating, hard-working, and exciting event in my life to that point. Although Alvin pilot training before the cruise was very thorough, the fear of the unknown kept it until the door was closed and lowered to the water.

What do I see? How dangerous is this? Will the sealed ball really protect me from the pressure of the pressure at the depth? How to be in such a small space with two more people eight hours? Will I remember all I need to do? Can I drink coffee? To my surprise, we went back to the surface before I realized it – the adrenaline level is still high.

This cruise and the results that came from successful exploration have marked the beginning of my career as one of the few geologists who work and study volcanoes in the mid-ocean reefs. From that diving in 1985, I had about 40 dives in Alvin to a depth of nearly 13,000 feet – up to the Alvin's caps just down the road. Since every dive usually takes six hours to the bottom, I spent a total of about 10 days at the bottom of the ocean – like "aquamarine".

Preparing for diving in depth

My typical diving preparation actually begins at the cruise planning stage shortly after the expedition is funded and a particular oceanographic vessel is scheduled. The exploration vessel Atlantis is specially equipped to host Alvin and manages multiple vehicles for deep descent during a dive. Most cruises last about a month, and 20 to 25 dives are planned in advance. A few days before each dive, researchers are exploring dive sites, discussing locations for specific sampling and metering.

The night before diving, scientists prepare a bag (mostly pillowcase) full of clothing and recording materials that they need. It usually includes a warm hat, trousers, sweater and extra socks for footwear while at the bottom because the submarine quickly becomes cold and damp in almost frozen deep sea water at a depth. I'm trying to relax because the typical osmosis dive can be mentally and physically exhausting.

I usually do not eat or drink in the dive in the morning and spend some time stretching out before I have to squeeze into a "ball", as it is called the inside of the sphere. Until 8 am, Alvin is out of order, moved to the disembarkation position and is ready for three aquasures to fall into the hole and settle in their place.

The interior of the Alvin Titan sphere during diving in the eastern Pacific in December 2018 shows a pilot in the middle and two scientists retreated under the electronics from both sides.
The Oceanographic Institute of Woods Hole, the National Fund for Deepwater and the National Science Foundation
Michael Perfit during one of his dives in Alvin to study sea volcanoes.
Molly AndersonCC BY-ND

The pilot sits upright in the middle of the ball, and my colleague and I are drawn to both sides of the electronics in the semi-lying position. There is not enough room for my feet in that position. The heavy cover above us is closed and airtight and waterproof to maintain atmospheric pressure during diving – now there is no return.

The pilot is turning to carbon dioxide purification devices that recycle the air we breathe for the entire dive and adjust the regulator that slowly passes extra oxygen into the sphere. At a height of just 6 feet, they can stand upright behind the place where the pilot is sitting, but he has seats only for one. Apart from stretching my legs, most of my time on my knees was looking from the front or side windows or writing notes on sample sheets.

Alvin was launched from the Atlantis research vessel during the recent diving series in the northeastern Pacific.
Michael PerfitCC BY-ND

Alvin lurking back and forth as he rose from the deck and swirled over the ocean to launch it. Then there is the comforting sound and feeling of our entry into the ocean as the seawater begins to cover five small circular windows. I can see divers floating around the submarine, checking if our equipment is still in place until they return the ship's recovery line.

After we pass through a number of equipment and safety tests, we get OK to start our slow downhill – we drop to about 110 feet per minute and will last more than an hour to 8,000 feet. The bright light from the surface reflects on the millions of small bubbles running around Alvin while releasing the air that helps us sink. Pretty quickly the sound of the boat fades and swinging from the surface waves stops. Compared to all the movements and noise on Atlantis, Alvina's interior is pleasantly quiet and peaceful, apart from air blowing and some music selected by a pilot in the background.

As we move all the way to the bottom, the outside light starts to fade quickly, at first it becomes greenish and then slowly very dark blue. Tiny red light lights illuminate the inside of the ball. We keep Alvin's outside lights in order to save the battery power we need to run at the bottom. After 10 minutes, deeper than 600 feet, almost light and hundreds of shiny bioluminescent organisms pass by the pan. This magical light show reminds me of the night sky I watched in the youth.

Half an hour passes and is about 3,300 feet in the "midnight zone" where there is no light and the glittering blue-green phosphorescence looks even brighter and dramatic. By this time I feel comfortable, but I'm looking forward to working at the seabed, trying to predict what we can see.

Science at the seabed

Approaching the sea floor, Alvin's outside lights are falling and we are scouting to let the pilot know when we see the bottom. For me, this is one of the most exciting dive sections that provokes anxiety because you never know what's going to be there. The very slowly ocean floor covered with lava and sediments begins to appear as if it is from the fog in the front lights.

For most of my dives, for security reasons we land from a volcanic and hydrothermal active cracking zone. These areas are usually covered with various types of flow – cushions, lobes, and filings of dust – depositing sheet. Closer to the crankshafts, the usual areas where the lava fl oor is full, overflow, then dry and decay. Some areas have a crowd of hundreds of feet tall lava pillow drains, which are drawn from the openings or transparent walls of about a hundred feet, which are pushed upward to the tectonic forces.

In some of the volcanic active areas, I found white, such as cotton organic mats that cover the black lava flows created by microorganisms living in the warm underground. Sometimes pieces of them rise upstream of the streams of hot water flowing from the cracks and the pit into the lava. I have seen hydrothermal openings that emit black smoke, rich in sulfur, typically surrounded by tubular worms, crabs, shells, shells and unusual creatures that can survive this extreme environment a thousand feet below the surface.

The Hydrothermal funnel with a black smoker in the eastern Pacific rises to 21 degrees N. The temperature sensor flickers to the left, and the titanium fluid samples can be seen in the lower right.
The Oceanographic Institute of Woods Hole and the National Foundation for Science

Six hours at the bottom I point the pilot where I go and what to sample or measure with Alvin's two extremely powerful but powerful hydraulic hands. More digital photos and video cameras set on Alvin's outer frame record our journey along the sea floor, while mini voice recorders and handwritten notes document our observations. Time passes quickly and rarely when we get everything we planned before the pilot records that our batteries are empty and that they discharge hundreds of pounds of iron weights in order to launch us for an hour.

Even with extra clothes, at the end of the dive, it becomes quite cold so additional blankets appear and usually fit with one of our packed peanut butter and jelly sandwiches. Bright lights announce our approach to the surface and I always hope that the sea must remain calm, otherwise we will feel uncomfortable bobbing while we wait for Alvin to recover.

Once you board Atlantis and when the opening is open, the relief is to fill my lungs with warm, fresh air and again to stretch your legs. Observation of recovery, congratulations to divers, especially new divers and sample testing we found was an evening event for scientists.

Michael Perfit describes observations during diving to scientists on the Atlantis ship shortly after the Alvin recovery.
Daniel FornariCC BY-ND

Over 45 years of geological features of the sea floor have been going on and I'm still excited to have dived into Alvin. We are still sampling, photographing, recording and watching, trying to answer questions about how to form over 60 percent of Earth's crust. How are undersea volcanoes come from and what are they made of? Where and why are deep-sea geysers – also known as hydrothermal openings – that emit liquids at 750 degrees? And how does life advance in these unsustainable environments?

Although there are many unmanned robotic submarines that can dive deeper depths for a long time, what scientists see on video screens on a boat from remote controlled vehicles can not be compared to the fact that they are at the bottom and seen in three dimensions.

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