he dazzling Researchers from Woods Hole Oceano- air. The same geothermal process creates on the shores of Rotomahana graphic Institution (WHOI) who joined the and mineral formations at Tat one time were the greatest national trea- the expedition­—Dan Fornari, Amy Kuku- Yellowstone National Park. sure of . They were cherished lya, and Robin Littlefield—said they had At the White Terraces, scalding, silica- by the Maori and known far and wide as never worked on a project with such deep laden water burbled from a crater about the eighth natural wonder of the world. cultural meaning. “This was actually a 100 feet above the lake and cascaded down Then, during an immense volcanic erup- burial ground,” said Kukulya. “Some of the about 50 wide, scalloped steps. As the water tion in 1886, they disappeared. people we met lost their ancestors there.” cooled, silica precipitated out of solution, “It was such an iconic feature to the dribbling over the steps and creating for- country,” said Cornel de Ronde, the New Not just another hot springs mations that looked like candle wax. The Zealand geologist who led a team that The terraces formed when a magma White Terraces covered an area equivalent rediscovered the Pinks in 2011. “In terms chamber heated groundwater and sent it to seven football fields. The Pink Terraces, of the people’s psyche and what it means spurting out of the ground, carrying dis- about half a mile across the lake from the to them, the equivalent for Americans solved minerals that rapidly crystallized Whites, were smaller but still impressive. would be the Grand Canyon.” when the water contacted the much cooler The colors of the formations probably arose

42 Oceanus Magazine Vol. 49, No. 2, Spring 2012 | www.whoi.edu/oceanus The Pink Terraces were tucked next to a hook-shaped spit of land, with the White Terraces in the background and looming behind. from differences in mineral composition access to them, provided canoe transport, soaks in the terraces’ warm waters. Tourists or microbial populations in their waters. and ran a small hotel nearby. Despite their and locals alike used to clamber up and To the Te Arawa, the Maori tribe remoteness, the terraces became a popular down the terraces looking for pools with with ancestral rights to the lake and its destination in the 1800s for wealthy Euro- just the right temperature to bathe in. surroundings, the White Terraces—or pean and American travelers with a taste One feature not visible in old photo- Te Tarata, “the tattooed rock”—were male. for adventure—and considerable stamina. graphs and paintings of the terraces was The Pinks—or Otukapuarangi, “fountain A trip to the terraces started with an the softness of the pool walls, caused by of the clouded sky”—were female. ocean voyage of weeks or months just to incomplete crystallization of the silica. “Like a lot of native peoples, the natural reach New Zealand. It continued with a Among the visitors surprised by their environment is where they draw their spiri- 150-mile coach ride from to Ro- spongy texture was English novelist tual side of things from,” de Ronde said. torua, a 15-mile hike through the bush, a Anthony Trollope. “So those terraces were a really big deal.” 7-mile boat ride across , and “I can imagine nothing more delicious The terraces also had great commercial finally a canoe ride on . to the bather,” Trollope wrote. “In the value to the Te Arawa, who controlled At journey’s end, travelers enjoyed long bath, when you strike your chest against Lake Rotomahana, and Mount John C larke Hoyte, Pink and White Terraces, ca. 1870s. Hocken C ollections, and gouache on paper, Watercolor Tarawera. o Hakena, U niversity of Otago. U are Taoka

Woods hole oceanographic institution 43 Three men enjoy a dip in a hot pool at geothermal activity persist: Geysers and the White Terraces, fumaroles dot the western shore, gas probably in the early bubbles rise to the surface in several parts 1880s. The scalding of the lake, and warm water occurs in water at the top of numerous locations. The world's newest the terraces cooled geothermal field, Waimungu, has arisen as it flowed down, at the southwest end of the lake. so bathers could find A secret hope water that was “just right.” The bumpy Although he grew up hearing tales of texture on the face of the Pink and White Terraces, de Ronde’s the pool is hardened primary reason for going to Lake Roto­ silica that precipitated mahana was scientific, not cultural. He out of the water. wanted to investigate the lake because the nidentified photographer, ca.1880s. A lbumen print. U nidentified photographer, N ew Z ealand Wellington, L ibrary, A lexander Turnbull terraces are among the few examples in the world of an above-water geothermal system it, it is soft to the touch. You press yourself assess the damage faced an impossible task, that has been drowned, and the only one against it, and it is smooth. You lie upon it, said de Ronde. for which scientists have an exact timeline and though it is firm, it gives to you. You “When they were up on the hills above of its disappearance. plunge against the sides, driving the water where the terraces had been and looked He had studied other volcanic geother- over your body, but you do not bruise your- down towards where things should be, A, mal systems, but those were at the bottom self. I have never heard of other bathing they can’t recognize anything; and B, there of the Pacific Ocean. On a survey of the like this in the world.” was this steaming, deep rift where the lake Brothers on the seafloor northeast used to be. So everybody just thought the of New Zealand in 2007, he had worked Devastation terraces had been blown to pieces.” with WHOI scientist Dana Yoerger, using The eruption started just after midnight But even then, he said, a few observers a WHOI deep-sea autonomous underwater on June 10, 1886. It didn’t just blow the suggested that the terraces might not have vehicle, or AUV. Two years later, on an ex- top off a single peak. A series of eruptions been destroyed; that they might still be pedition to the Kermadec Arc seamounts, went on for hours and opened a rift more there, under the mud. he collaborated with Fornari, a marine than ten miles long—right through the Debris thrown out by the eruption geologist with decades of experience lake floor and beyond. blocked the stream that had drained the studying seafloor volcanism and undersea “It started at Mount Tarawera, and it old Lake Rotomahana, so as water contin- “hot springs” called hydrothermal vents. went northeast first and then it kind of ued to flow in, the crater began to fill up. A conversation with Fornari on that turned around and went southwest and un- Within 15 years of the eruption, a new lake cruise led to a collaboration to explore the zipped underneath the old Lake Rotomah- had formed, drowning the area where the geothermal system in the lake. Finding the ana,” said de Ronde. That’s when it turned terraces had been. terraces was never part of the official plan. most deadly. When the superhot magma Today’s Lake Rotomahana is about five “If you go to a government funding hit the cool lake water and water-saturated times bigger and up to 12 times deeper agency and say, ‘We’re going to look for ground, it caused a massive steam explo- than the pre-eruption lake. Its shores are something that 99.9 percent of people sion that opened a crater several times the once again thick with forest, and signs of thought was gone,’ you would have no size of the lake and hurled tons of lakefloor sediment for miles around. Rewiri, a Te Arawa “The whole lake was excavated, essen- man, sits in front of tially, and all of that mud and debris splat- a house at the village tered all the surrounding valleys, killed of Te Wairoa soon 120 people, and just devastated the land- after the 1886 scape,” said de Ronde. “For many, many eruption of Mount years this land was completely uninhabit- Tarawera. The village, able. We’re not just talking a sprinkling of which lay about 7 miles from the ash. We’re talking meters thick of mud.” The Te Arawa who survived had little volcano, was almost left but their lives. The entire tribe dis- completely buried by persed, some moving up to 200 miles away mud and ash. Fifteen and most having to ask permission to live people died there. on other tribes’ land. Two other Maori The terraces had disappeared, but it was villages were also impossible to say what exactly had hap- destroyed, with no Burton Brothers, 1886. S ilver gelatin print. pened to them. A surveying party sent to survivors. N ew Z ealand Wellington, L ibrary, A lexander Turnbull

44 Oceanus Magazine Vol. 49, No. 2, Spring 2012 | www.whoi.edu/oceanus LOST GLORIES, FOUND

chance of getting the money,” de Ronde Scanning the lake driven propellers, steered by fins, and said. “I also didn’t want to get people’s Lake Rotomahana is still very isolated; guided by an onboard computer. They have expectations up, because to be honest, giv- to get there each day from their motel, the a long track record in ocean work, but they en what had been written, I wasn’t overly researchers drove 15 minutes on a highway, had rarely been deployed in and never confident that we would find anything. then 15 minutes on a paved road through been used to survey hydrothermal features. “But secretly, at the same time, I said pastureland, then nearly 20 minutes on a On this project, the REMUS vehicles to myself, ‘We’ve got this state-of-the-art four-wheel-drive road, finally reaching a carried a typical payload of multibeam and gear to go have a look, and maybe we can put-in point just large enough for one ve- sidescan sonars. They also were equipped figure out what happened to the terraces.’ ” hicle to back the boat it was towing into with instruments never mounted on them So in January 2011, Fornari, Little- the water. before: pH sensors; a magnetometer to de- field, and Kuku- tect magnetic field lya flew to New properties that Zealand, joining could indicate past Sharon Walker of hydrothermal activ- the U.S. National ity; and a MAPR Oceanographic (Miniature Au- and Atmospheric tonomous Plume Administration, Recorder) from Vicki Ferrini of the NOAA, which Lamont-Doherty measured a host of Earth Observatory water characteris- in New York, and tics that could help de Ronde and other locate hydrothermal researchers from features. New Zealand’s “We wanted to GNS Science agen- do water properties cy and the Univer- and bottom map- sity of Waikato. ping at the same Their goals were to time” to overlay all map the lake floor the data on a single and search for signs map, said Fornari. of hydrothermal “It was a very features in its water. multidisciplinary Before starting geology-chemistry- out, the research- sampling-surveying ers went through type of operation.” a welcoming cere- The team ran mony offered by Te the REMUS ve- Arawa elders that hicles on grid pat- reinforced the deep terns back and forth spiritual value the across the lake us- lake and terraces ing the multibeam held for them. sonar to map the “We walked floor. At the same down this reception time, the MAPR’s line, and with every chemical sensors person we would L loyd Homer © I nstitute of G eological and N uclear S ciences imited took readings of In the 1886 eruption of Mount Tarawera (the flat-topped mountain at far end of lake), a rift more shake hands and do depth, temperature, than 10 miles long tore through the floor of Lake Rotomahana and beyond. the hongi, or ‘fore- salinity, and turbid- head kiss,’ where ity of the water. you lean forward and touch noses,” said The researchers' ambitious project plan They had hoped to identify lake-bottom Kukulya. “We had to hold it until the other had to be completed in just nine days, af- features as small as 1 meter but because of person decided to break contact.” ter fierce storms delayed their start. They technical difficulties, they could get to a Elders of the Te Awara also went with would use two AUVs called Remote Envi- spatial resolution of only 15 meters. That them to the lake on the first day to offer ronmental Monitoring UnitS, or REMUS, was still a huge improvement over the pre- a blessing on the endeavor. Torrential slim robotic vehicles originally developed vious map, done in 1975, whose 200-meter rain during the ceremony was considered a at WHOI to survey the seafloor in shallow resolution would not have shown the ter- good sign for the project's outcome. coastal areas. They are powered by battery- races even if they weren’t covered by mud.

Woods hole oceanographic institution 45 Julian Thomson, GNS S cience C ourtesy of D an Fornari, WHO I C ourtesy of D an Fornari, WHO I Dan Fornari and Robin Littlefield of WHOI send Appearance of shorelines past the entire area, that could tell you where a REMUS 100 on its mission to map the lake Running out of time and with the you were. We mapped the whole lake floor, floor. Later, Fornari's camera revealed the rosy, multibeam not working as well as they’d and lo and behold, this 'hook' jumped out bumpy buttress of a Pink Terrace. hoped, the team sent a REMUS close of the map. It was like, ‘bingo!’ ” to the lake’s shoreline where de Ronde It was “bingo!” again when Ferrini Watch the video at: thought the Pinks should be, if they had analyzed the sidescan images. In exactly whoi.edu/oceanus/terraces survived. That vehicle used sidescan sonar, the right place were curved structures that which detects sound reflections from hard looked like the scalloped front edge of a objects on the lake floor. terrace. Just north of them was a ramp “The terraces were never destroyed,” They also sent down a camera system angling upward, which the team thinks he said. “They never went anywhere. Fornari usually deploys from a ship. At could be the rest of the Pink Terraces, What happened to them is that they got first, since they had not yet seen the mul- still covered by mud. completely and utterly covered in up to 10 tibeam map or sidescan images, they made Their excitement building, Fornari meters of thick mud, which was all exca- an educated guess about where best to downloaded photos from the same area vated out of the old lake.” And then, when deploy the camera. Later, they focused on taken by his underwater camera—and the waters rose, they and their muddy highlights found by the sidescan. there they were, the buttresses of several cloak disappeared from view entirely. At the motel that evening, they began terraces, complete with the “candle wax” piecing together information from all their texture on their outer faces. They were Searching for the Whites instruments. Hoping that some of the for- even pink. Other photos showed ripples on The team found the boundaries of the mer shoreline would still be recognizable the nearby lake floor, indicating a current. old geothermal system from their magnetic under water, the researchers pored over old “The only terraces that we can see survey and established that it is still active photos, paintings, and maps of the lake are right at the bottom,” said de Ronde. under the lake. They also found a huge looking for features that might match up “I think they’re exposed simply because geothermal system in the southern part of with the contours on their new map. they’ve had these currents winnow away the lake that had formed since the eruption. There wasn’t much to go on. the sediment sitting on top of them. The researchers were surprised by the “The 1886 lakeshore of - Otherwise I don’t think we would have scale of the geothermal activity they found. hana was very boring in the sense of land- seen even that.” Analysis of lake water samples revealed marks, except for one,” said de Ronde. So at least some of the Pink Terraces high levels of carbon dioxide and helium “Immediately north of the Pink Terraces, are still there, and, apparently, intact. gas—“way more than we would expect there’s this hook-shaped piece of land that De Ronde thinks they survived because from your normal geothermal system,” said juts out from the lakeshore. All the pho- they were far enough from the rift not de Ronde. “Which means we have a very tographs from before the eruption show it. to get blown to bits or collapse into it. A actively degassing magma chamber not far So there’s this feature, this one feature in follow-up study in 2012 confirmed that. below the lake floor.” The geologists even turned up evidence that is generating buzz among biologists— “It’s not just a scientific discovery or photos of sponges on the lake floor that resemble a species that lived in the much an adventure thing. It’s actually shallower, pre-eruption lake. Where they came from and whether they are a new a deep part of who we are. Even species or the same species that adapted quickly to the new habitat are questions myself—I never realized how waiting to be addressed. The team worked 18-hour days, meaningful it would be.” scrambling to gather as much information as they could in the short time they had. —Cornel de Ronde They had hoped to carefully search the C ourtesy of ornel de R onde area where they thought the White

46 Oceanus Magazine Vol. 49, No. 2, Spring 2012 | www.whoi.edu/oceanus LOST GLORIES, FOUND

Mount Tarawera

APPROXIMATE PRE-1886 PRESENT-DAY SHORELINE ERUPTION SHORELINE ft Ri n tio Approximate Location up Er of White Terraces 86 18

Island

Distinctive Feature of 1886 Shoreline Location of Pink Terraces on Keam; bathymetry: Vicki Ferrini/ LDE O; D an Fornari, A my Kukulya, and R obin L ittlefield/WHO I ; C ornel de onde/ GNS S cience P re-eruption outline: R on Keam; bathymetry: Vicki Today's Lake Rotomahana (white) is much Terraces were, but they suffered what the 125th anniversary of the eruption. larger than the pre-eruption lake (black outline). Fornari called a “gotcha!” In the meantime, the expedition had With sonar data collected by REMUS vehicles, Old photos and paintings of the Whites taken on deep personal significance for de Vicki Ferrini of Lamont-Doherty Earth Observa- area after the eruption show a rocky hill Ronde. While on the lake one day, he got tory made this color-coded bathymetric map of next to it, dubbed the Pinnacle. During a call from his partner: She was pregnant the lake floor. It revealed a distinctive feature their initial survey, the researchers found with their first child. The couple asked a (inset) also seen in pre-1886 photos of the the submerged Pinnacle the hard way: A Te Arawa spiritual leader to suggest two lakeshore. Photos taken by Dan Fornari's cam- REMUS ran into it. The vehicle wasn’t middle names, one for a boy and one for a era system showed parts of the Pink Terraces hurt, but the team steered clear of the girl. In October, they welcomed a daugh- near that feature. Researchers think remnants obstacle after that—which prevented them ter, Scarlett Otukapuarangi de Ronde. of the White Terraces lie just north of an area from mapping the likely site of the White (white patch) they were unable to scan with Terraces. On their last day on the lake, Sacred ground the two REMUS vehicles. they did a few sidescan runs as close to the At the end of the expedition, the re- area as they dared to go, and then it was searchers shared the news about the Pink had been a place where people had per- time to pack up and head home. Analysis Terraces. First to see the maps and pho- ished in the natural disaster, there was a of those sonar images would have to wait. tos were the Te Arawa, who were pleased whole different level of engagement and A few months later, de Ronde got an by the team’s follow-through on its plans interest from the point of view of the e-mail from an excited Vicki Ferrini. She and its promises to keep them informed, Maori there,” he said. “There were still had finally looked at the sonar images, and de Ronde said. “One of the things said to some people who remember their grand- at the very edge of the area they surveyed us at the end by one of the elders was that parents or great-grandparents telling near the Pinnacle were a couple of struc- ‘You came, you said, and you did,’ and they them stories about the eruption or who tures that looked like terraces. The features were really impressed by that.” had actually lived near the lake. It wasn’t were in just the right place to be part of the Many of the people who heard the that long ago.” White Terraces, but without sonar of the presentation were moved to tears. Fornari, “It’s hard to put into words,” said de whole area, the scientists couldn’t be sure. who has worked on research vessels all Ronde. “It’s not just a scientific discovery The White Terraces were closer to the over the world, said he has never experi- or an adventure thing. It’s actually a deep rift than the Pinks and may have been enced such a deeply personal response part of who we are. Even for myself— severely damaged. The team publicly to his work. I never realized how meaningful this announced the find on June 10, 2011, “Because it was sacred ground and it project would be.”

Woods hole oceanographic institution 47