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Diving Iceland's Hydrothermal Vents

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Diving Iceland's Hydrothermal Vents StrýtanDiving Iceland’s Hydrothermal Vents Text and photos by Michael Salvarezza and Christopher P. Weaver 50 X-RAY MAG : 65 : 2015 EDITORIAL FEATURES TRAVEL NEWS WRECKS EQUIPMENT BOOKS SCIENCE & ECOLOGY TECH EDUCATION PROFILES PHOTO & VIDEO PORTFOLIO Strýtan’s chimneys are covered with colorful anemones (right and previous Iceland travel page); A pair of tunicates (below) The waters of the Eyjafjordur Fjord were still and calm. There was a sharp crispness to the air and snow covered the hills lining the shore. Except for the gentle lapping of water against the sides of our inflatable dive boat, the world around us was silent. To the north we could see heavy gray clouds hanging low to the horizon, the first signs of an approaching storm undoubtedly born in the Arctic wilderness just a few miles away. In a few short hours, the weather would turn bad and diving would become impossible. For now, all was calm and we were focused on preparations for an underwater adventure to an alien world. In 1997, divers Erlendur Bogason and tion rising to over 200ft (230m) from deep. Currently, Strýtan is the shallow- per second. his friend Árni Halldósson discovered the ocean floor to nearly 50ft (15m) est known vent in the world and the These geological formations are an amazing hydrothermal vent in the below the surface. only place where scuba divers can formed by smectite, a white clay dark waters off the shores of Hjalteyri, Hydrothermal vents have been dis- actually dive on an active hydrother- material that mixes with other crustal a small fishing village located near covered in many places throughout mal vent. A white smoker, Strýtan is a elements and minerals as it circulates the town of Akureyri. Strýtan, as this the world, usually along continen- set of chimneys that continually emit through the oceanic crust under very location has been named, is a tower- tal rift zones, but they are generally very hot water 167˚F (75˚C) at an esti- high pressure and temperature. When ing chimney-like geological forma- located many thousands of feet mated rate of 26 gallons (100 liters) this material mixes with the cold 51 X-RAY MAG : 65 : 2015 EDITORIAL FEATURES TRAVEL NEWS WRECKS EQUIPMENT BOOKS SCIENCE & ECOLOGY TECH EDUCATION PROFILES PHOTO & VIDEO PORTFOLIO travel Iceland CLOCKWISE FROM FAR LEFT: Divers exploring Strýtan’s vents; Hot water emerg- es from Strýtan at an astonishing rate; Dramatic scenery at one of Iceland’s fjords; Strýtan’s chimney ocean water after emerging installed a mooring buoy to from the ground, it coagulates, ensure the protection of this deli- hardens and forms the chimney. cate environment and to help Strýtan started forming at the divers find their way to the site. end of last ice age 10,000 years Descending into the waters of ago. the fjord, our eyes opened wide At Strýtan, divers can explore as the first glimpse of the chim- these towering formations and ney came into view. will marvel at the marine life that At first, Strýtan appears as a abounds in these waters. tall, narrow spire—rocky, cov- ered with multi-colored plumose Diving anemones, but otherwise some- Our dive began with a routine what uninteresting... until you back roll into the teeth-chatter- get close. ing 34˚F (1˚C) water. Instantly, After just a few minutes, we our eyes adjusted to the dim became aware of hazy, “out of light of the greenish-black water. focus” water—the telltale sign of Peering down through 50ft (15m) hot fresh water mixing with cold visibility and searching for some- salt water. These haloclines and thing to orient ourselves, we thermoclines were easy to spot focused first on the down line. and were the best evidence of Bogason, who operates the the rushing geothermal water nearby Strýtan Divecenter, has flowing into the fjord. Scientists 52 X-RAY MAG : 65 : 2015 EDITORIAL FEATURES TRAVEL NEWS WRECKS EQUIPMENT BOOKS SCIENCE & ECOLOGY TECH EDUCATION PROFILES PHOTO & VIDEO PORTFOLIO travel Iceland CLOCKWISE FROM LEFT: Ferocious looking but harmless wolffish; White- plumed anemones decorate Strýtan’s chimneys; Weird-looking lumpsucker; Flabellina sp. nudibranch; Hermit crab studying this phenomenon estimate that home to a wide array of interesting marine filmed by Bogason for National Geograph- the water emerging from the cone is life. Macro enthusiasts will spot colorful ic. Despite the rugged appearance, it is about 1,100 years old. Flabellina sp. nudibranchs, along with crus- actually a fragile environment. Careless Normally, divers in very cold water never taceans, sponges, starfish and anemones. divers who don’t pay attention to proper remove their gloves—but at Strýtan, things Swirling around the chimneys are schools buoyancy can quickly damage rock for- are a bit different! Divers here can care- of cod and pollock. Sharp-eyed divers mations that have taken thousands of fully remove their gloves and warm their will also encounter starry rays, the curious years to form. Visitors are strongly advised hands in the hot water flowing out from lumpsucker fish and the ferocious looking to be careful and respectful. the cone—a unique method of hand wolffish. Nearby in the same waters are other warming on a cold-water dive! Strýtan is the first protected underwater dive sites worth visiting. area in Iceland, gaining this status in 2001. Arnarnesstrýtur, sometimes referred to Marine life and protected areas This unique location has received world- as “Little Strýtan”, is a cluster of smaller In addition to geological marvels, Strýtan is wide scientific attention as well as being hydrothermal vent cones covering an 53 X-RAY MAG : 65 : 2015 EDITORIAL FEATURES TRAVEL NEWS WRECKS EQUIPMENT BOOKS SCIENCE & ECOLOGY TECH EDUCATION PROFILES PHOTO & VIDEO PORTFOLIO travel Iceland Nesgla underwater (left); Diver explore the famous Silfra fissure (above) This water, filtered for 50 years Silfra, one of these geological cracks through miles and miles of lava rock, and one of the most iconic dive sites emerges here as clear and clean as in all of Iceland. possible. It is here that divers can visit At Silfra, divers descend a set of area 1,312 feet (400m) by 3,281 feet and flooded with water of unbeliev- (1,000m) with an amazing variety of able clarity. Opportunities also exist to marine life. Arnarnesstrýtur was pro- dive with spawning cod fish in early tected in 2007 and became the sec- April, and to experience diving sea ond protected underwater area in birds off Grimsey Island, a small island Iceland. north of Iceland and located right on The French Gardens is a sublimely the Arctic Circle. In the harbor near beautiful, though rarely visited site Akureyri, the wreck of the Standard consisting of additional cones and lies in shallow water. A German bark, vents. Standard was built in 1874, sunk in 1917 and discovered in 1997. Additional adventures Two hours outside of Reykjavik is Diving in Northern Iceland is a unique Thingvallavatn Lake, home to a rup- adventure. Here, divers can experi- tured landscape torn apart by geo- ence the wonders of Earth’s geologi- logical forces. In and around the lake cal forces by visiting the underwater are many fissures and tectonic cracks, hydrothermal vents or by diving in many of them filled with glacial melt Nesgla, a crack or fissure in the Earth’s water from Iceland’s second largest crust formed through tectonic activity glacier, Langjokull. Dramatic views from the road through Northern Iceland; Comb jelly in frigid waters of Northern Iceland (left) 54 X-RAY MAG : 65 : 2015 EDITORIAL FEATURES TRAVEL NEWS WRECKS EQUIPMENT BOOKS SCIENCE & ECOLOGY TECH EDUCATION PROFILES PHOTO & VIDEO PORTFOLIO travel Iceland Divers enjoy crystal clear water in Silfra (left and top right); Dramatic waterfalls adorn the Northern Iceland boat harbor (left Icelandic landscape (above) inset); Sea urchin (above inset) stairs installed for safety and canoes, the land is rela- access, and then enter a tively young and is still being labyrinth of rock walls, boulder formed. It is also a country piles, cavities and crevices all steeped in history, includ- filled with some of the world’s ing strong cultural ties to the purest water. In fact, div- Vikings, and is home to the ers are encouraged to taste the water Topside wonders site of the very first Parliament meeting in along the way! Topside, Iceland is an amazing contrast the year 930 AD. Unique to Silfra, divers can actually between civilization, history and wilder- In fact, visitors can experience the reach out and simultaneously touch ness. With only 320,000 people residing most exciting natural attractions Iceland both the North American and Eurasian in the entire country, many of them in has to offer in one afternoon by tak- tectonic plates. Diving here is akin to the main city of Reykjavik, much of the ing the Golden Circle tour. The Golden being transported to another world— country’s landscape is natural and undis- Circle is a very popular tourist route cov- with visibility exceeding 300ft (91m), tem- turbed. Visitors can experience black, ering about 186.4 miles (300km). The tour peratures hovering around 34°F (°1C) barren fields of pumice and lava stone, loops from Reykjavík into central Iceland and a gentle flowing current, the dives breathtaking waterfalls, lovely seaside and back again. are magical and transformative. communities and dramatic mountains. There are a number of tour companies Home to more than 30,000 live vol- that offer this tour, most of which offer 55 X-RAY MAG : 65 : 2015 EDITORIAL FEATURES TRAVEL NEWS WRECKS EQUIPMENT BOOKS SCIENCE & ECOLOGY TECH EDUCATION PROFILES PHOTO & VIDEO PORTFOLIO A giant stride into the Nesgla fissure (left); North Atlantic codfish (lower left); Iceland travel Nudibranch (below) ICELAND INFORMATION GETTING THERE: International visitors arrive in Iceland into Keflavik Airport.
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