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Something old, something new Geyser experts note changes in patterns at Norris By MICHAEL MILSTEIN Gazette Wyoming Bureau YELLOWSTONE NATIONAL PARK - Echinus Geyser, one of the most regular and popular performers in Yellowstone National Park's Norris Geyser Basin, has slowed its pace in recent months, while Steamboat Geyser, the tallest geyser in the world when active, is showing signs of life for the first time in years.
Echinus had long erupted roughly every 40 to 80 minutes, making it the largest predictable geyser at Norris and a perennial crowd-pleaser. Signs at the geyser still advise visitors to watch for eruptions every 70 minutes or so, but in recent months the geyser's vigor has declined so much that it has sometimes gone more than four hours without an eruption. "Someplace we either lost energy or heat," said Smokey Sturtevant of Billings, a longtime Norris geyser watcher. "It's difficult to know what happened, but that's one of the things that make Norris so interesting." Echinus does not spout as high as better-known Old Faithful, but its eruptions often display more personality in the form of explosive bursts and powerful splashing that sometimes sprays visitors watching from grandstand-style benches. Its pool gradually fills before an eruption and then, after an eruption, quickly drains and the cycle begins again. The geyser's eruptions began growing more "anemic" last year and slowed through the winter, Sturtevant said. While he was visiting Norris last weekend, he said, Echinus was quiet for more than four hours. The definitive book, "The Geysers of Yellowstone," by T. Scott Bryan says that prior to 1948 Echinus often sat dormant, but ever since then has remained "the one large geyser you can count on seeing at Norris." Geysers erupt when the hot water filling their plumbing flashes violently into steam and shoots skyward. A shift in heat or water could leave a geyser short of the energy it needs to erupt. Park Ranger Bill Wise, who works at Norris during the summer, said "false starts" of Echinus have grown much more common. A false start occurs when the geyser begins splashing as if it's about to begin erupting, but then stops before surging into a full eruption. Echinus has lately averaged one to four false starts before each eruption, he said. Just up the trail from Echinus in Norris' "Back Basin," though, a perking Steamboat Geyser has caught the interest of geyser gazers. When active, Steamboat fires water more than 250 feet high, making it the tallest geyser in the world. It last erupted on Oct. 2, 1991, and since then has been marked mainly by quiet steaming and occasional low splashes of water. Steamboat began gaining steam last year, though, and has sometimes thrown water 30 feet high or more. While such spraying by no means suggests that a major, skyrocketing eruption is imminent, it may reassure geyser fans that Steamboat has not gone into retirement. Water levels and temperatures are also up slightly at nearby Cistern Spring, believed to be linked to Steamboat through underground plumbing. "There's more water in the system than there has been in several years," Sturtevant said. "It's still nothing to get me excited, but it is something to watch." Major eruptions of Steamboat are rare spectacles, typically beginning with minor splashing and bursts of water that grow higher until the geyser's column of water towers over the landscape. Even when active, Steamboat rarely erupts more than a few times a year. But to geyser aficionados, its dramatic performance is the Taj Mahal of hydrothermal geology. Geyser lore includes the story of Hazel Decker of Two Harbors, Minn., who in the late 1960s and early 1970s was one of Steamboat's most dedicated observers, once keeping watch over the geyser for 52 days straight. "If a major eruption seemed close, she would sometimes spend the night sleeping in her car in the parking lot, hoping to be there as soon after it started as possible," according to a history of Steamboat written by the late Yellowstone geologist Roderick "Rick" Hutchinson. "One eruption in 1968 began at 2 a.m., at which time she woke up the campground ranger at Norris Campground where she was staying, and the naturalist at the museum. Mrs. Decker is reported to have stayed at the geyser from 2:15 a.m. until 2:30 p.m., and to have made more visitor contacts than the rangers did!" Geyser watchers have also noticed other recent changes at Norris, including more frequent eruptions by Veteran Geyser and a slowdown in the eruptions of Whirligig Geyser. Several swarms of small earthquakes have jiggled the Norris area over the past few months, possibly rearranging the geyser schedules. But the full effects of such tremors may not reveal themselves for weeks or even months afterwards. "It's going to be an interesting summer at Norris," Sturtevant said. "There is a significant shift of heat in the system, but where it's all going to lead, we don't know." To the south, at Black Sand Basin near Old Faithful, geyser gazers earlier this year noticed rainbow-colored Sunset Lake erupting as a geyser. The broad pool of steaming water, a small version of the often-photographed Grand Prismatic Spring, was first known to erupt following the 1959 Hebgen Lake earthquake that temporarily turned many placid Yellowstone springs into geysers. It later erupted sporadically into the 1980s, but has remained generally quiet during the last 10 years or so. Steam rising off Sunset Lake often shrouds its eruptions, especially on cold days. Nearby Green Spring, which former park geologist George Marler speculated might have underground connections to Rainbow Pool, has also begun erupting in recent months. Few people have actually seen the eruptions, though, because they apparently have occurred only once or twice per day.
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