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Geoscenario Resources—Yellowstone : Task Now that you have explored as a team, the general story of the , it is time for each of you to dive into more specialized information. The geologist focuses on the historic path of the Yellowstone Hotspot and how the major geothermal features work. Add helpful details to your notes for Geoscenario Team Questions. Then work together and combine all the information to successfully present your story of the Yellowstone Hotspot. Questions for the Geologist to Consider • How do the major geothermal features in Yellowstone work? • What is the historic path of the Yellowstone Hotspot? Information Water cools near the vent’s surface. Yellowstone National Park is known for its This cooler water “caps” the hotter diverse hydrothermal features. How do they water below. Eventually, superheated work? These diagrams explain how build Side channels can often release pressure water flashes to steam, expanding and within thermal systems. Side channels lifting the water above the vent in an pressure to erupt and why hot springs are so blue. can act as indicators of when primary- eruption. The brilliant colors in hot springs come from feature eruptions may occur. archaebacteria. Aptly called extremophiles for Silica is dissolved from (the their ability to survive in extreme environments, Side Channel volcanic rock) and precipitates as these colorful organisms can live in extremely sinter, which forms the cone. high temperatures. Scientists study these bacteria Sinter Sinter to understand how their cells and proteins can Sinter is deposited on the walls and acts High-pressure area caused by survive and function in environmental conditions like a throttle in the vent by constricting expanding water and steam. far beyond the tolerance of most life. water circulation and allowing pressure to build up. Mud pots are drier than hot springs. Sulfuric acid disolves the surrounding sediments into the Recharge of superheated water. muddy pots. Fumaroles, or steam vents, are hot Courtesy of National Park Service springs with a lot of heat but so little water that the water boils away before reaching the surface. A hot spring shows colors caused by the presence of archaebacteria. © iStockphoto/ Wallentine

Hot springs are the most numerous type of thermal feature in Yellowstone. Water temperature within some springs is as hot as 93°C (199°F). The intense blue color of some springs results when sunlight passes into deep, clear waters.

Mud pot © iStockphoto/tupungato Courtesy of National Park Service Volcanic fumarole steam © iStockphoto/ ChuckSchugPhotography FOSS Next Generation Yellowstone National Park—Page 1 of 8 © The Regents of the University of Version date November 20, 2018 Can be duplicated for classroom or workshop use. The Hawaiian (with the youngest (Hawaii) closest) and the direction of the . Formation of the Hawaiian chain. Courtesy US Geological Survey /Joel E. Robinson, Will R. Stettner not only study the current active 4.5 mya: Kilgore forms from eruption in features in Yellowstone, but they also ask questions Plain that expels 1,800 km3 of ash. about ancient active areas and the patterns in 1872: Yellowstone is designated as the first the landscape. Satellite images have allowed national park in the United States. geologists to view a pattern of ancient through the that become 1972: Jason Morgan uses ages to progressively older southwest of Yellowstone. calculate the southwest motion of the , at 1-2 cm/year. The islands of Hawaii also offer a nice example of how a series of volcanoes can form when a plate 1994: Geologists at the moves over a heat source. recalculate plate movements to current rates. Events Vocabulary 16-8 mya: North American Plate moves fumarole steam vent southwest by 6.1 centimeters (cm) per year. geyser hot spring with underground spaces that 12-10 mya: Bruneau-Jarbidge eruption in the trap steam pressure and create periodic eruptions Snake River Plain expells 250 cubic kilometers hot spring a naturally occurring warm body of (km) of ash, creating ash-fall beds in the water Northeast, 1,600 km away. hydrothermal feature surface feature created 8 mya: North American Plate slows to move from underground superheated water southwest 3.3 cm/year. mud pot an acidic hot spring that dissolves rock 6.6 mya: Blacktail Tuff forms from eruption in to create a hot, muddy, bubbling spot 3 Snake River Plain that expels 1,500 km of ash. mya million years ago

Track of the Yellowstone Hotspot Like the Hawaiian Hotspot and the Pacific Plate, the North American Plate has Courtesy US Geological Survey been moving over the Yellowstone Hotspot, melting a path through the . The red dots indicate , and the yellow and orange circles show the ancient calderas. Courtesy US Geological Survey FOSS Next Generation Yellowstone National Park—Page 2 of 8 © The Regents of the University of California Version date November 20, 2018 Can be duplicated for classroom or workshop use. Geoscenario Resources—Yellowstone Hotspot: Seismologist Task Now that you have explored as a team the general story of the Yellowstone Hotspot, it is time for each of you to dive into more specialized information. The seismologist focuses on what a hotspot isand where major hotspots are found across the world. Add helpful details to your notes for Geoscenario Team Questions. Then work together and combine all the information to successfully present your story of the Yellowstone Hotspot. Questions for the Seismologist to Consider • What is a hotspot? • Where in the world are the major hotspots? Information In 1963, John Tuzo Wilson came up with a theory Plain, where the Yellowstone Hotspot triggered to explain volcanic activity in the middle of numerous caldera supereruptions before the continental plates or more-than-normal activity plume began feeding Yellowstone, about 2 million along faults. Wilson described stationary years ago. chambers, or hotspots, beneath the plate’s crust, which could cause volcanic activity far from any boundary zone. Since then, scientists have been able to create images of the Yellowstone Hotspot using seismic technology. Scientists at the University of Utah constructed an illustration of the Yellowstone Hotspot plume beneath Yellowstone National Park. Researchers believe that blobs of hot rock float off the top of the plume, then rise to recharge the located 6–16 kilometers (km) beneath the surface. The illustration also shows a region of warm rock extending southwest from near the top of the Yellowstone underground plume. The park boundaries are outlined in green at the top plume. It represents the eastern Snake River of the illustration. The , or giant volcanic crater, is outlined in red. State boundaries are shown in black. The park, caldera, and state boundaries are also projected on the bottom of the illustration to better show the plume’s tilt. 1 mile = 1.6 km. Courtesy US Geological Survey University of Utah

This map shows some of the most established hotspots in the world. Courtesy US Geological Survey FOSS Next Generation Yellowstone National Park—Page 3 of 8 © The Regents of the University of California Version date November 20, 2018 Can be duplicated for classroom or workshop use. Other Major Hotspots the . Unlike and the Mid- The Hawaiian Hotspot is one of the best-known Atlantic Ridge, four major reservoirs feed this and most studied hotspots. It was the basis for hotspot, causing changes in volcanic activity. Wilson’s understanding of how plates move over Thus, land formed on both sides of the divergent magma plumes. Ancient fishers first noticed that boundary over the past 20 million years. the islands got sequentially older as you moved toward the northwest. Notice the abrupt change in direction from the north-south Emperor Seamount chain to the southeastern progression of the chain of the Hawaiian Islands. Scientists continue to debate whether this change happened because of an abrupt change in plate movement or a shifting hotspot.

© iStock photo/Liz Leyden The Hotspot lies beneath the junction of three of the world’s largest tectonic plates (the North American Plate, the , and the ), creating islands on all three plates. The Azores were uninhabited when Portuguese navigators arrived in the early 15th century. Because these young, remote islands were settled over two centuries, culture, dialect, and traditions vary from island to island. The main sources of income for all the islands are farming, fishing, and tourism.

Courtesy US Geological Survey

The island of Iceland was created by a hotspot beneath the Mid-Atlantic Ridge. The abundant geothermal reservoir, provided by the , combined with hydropower from many rivers and waterfalls, supply all of Iceland’s electricity. This accounts for about 80 percent of the nation’s total energy. Iceland plans to be © iStock photo/Mlenny independent from oil by the year 2050. Events 1946: A model of the Hawaiian Islands by ages is created, based on dating of surface rocks. 1963: John Tuzo Wilson develops hotspot theory. Vocabulary caldera a cauldron-like feature formed when the center of a collapses after a major eruption © iStockphoto/Rob Broek In the eastern Pacific Ocean near the equator, the hotspot volcanic regions that are fed by Galápagos Islands have as complicated superheated areas in the underlying mantle. and mysterious as their ecology. The Galápagos These can be found near or far from plate Hotspot rests beneath the , and, like boundaries. Iceland, it is near a divergent boundary with a thermal dome of hot rock that rises through ’s mantle and creates a hotspot FOSS Next Generation Yellowstone National Park—Page 4 of 8 © The Regents of the University of California Version date November 20, 2018 Can be duplicated for classroom or workshop use. Geoscenario Resources—Yellowstone Hotspot: Volcanologist Task Now that you have explored as a team the general story of the Yellowstone Hotspot, it is time for each of you to dive into more specialized information. The volcanologist focuses on how major eruptions have historically affected Earth and predictions of when Yellowstone could erupt again. Add helpful details to your notes for Geoscenario Team Questions. Then work together and combine all the information to successfully present your story of the Yellowstone Hotspot. Questions for the Volcanologist to Consider • How have major eruptions in the past impacted Earth? • When did the erupt? When could it erupt again? Information Ash particle (magnified 200 times) showing the jagged surface. Volcanic eruptions can have remarkable global Courtesy of US Geological impacts—from burying forests to causing climate Survey cooling to possible involvement in three of the world’s greatest mass extinctions. More recent, smaller eruptions have helped scientists observe atmospheric effects, shedding light on how from the 1980 Mount ancient eruptions affected the planet. St. Helens eruption Courtesy of Effusive eruptions are a gentle and steady US Geological Survey outpouring of . Explosive eruptions usually involve thicker felsic magma that becomes volatile as it approaches Earth’s surface. Explosive eruptions are measured by the size of the caldera and the amount of volcanic ash released into the atmosphere, which eventually settles out and creates layers of rock called tuff. Influential effects of eruptions include ash fall, haze effect, and ozone depletion. Even a light dusting of volcanic ash can cause respiratory health problems and damage crops, electronics, and machinery. When ash mixes with Eruptions at Yellowstone in the past have spread ash over much of the United States. rain, it creates heavy cement-like substances that The biggest eruption formed the Huckleberry Ridge ash bed. can collapse buildings. Courtesy of US Geological Survey Particles such as dust and ash can block Earth’s sunlight, thus reducing solar radiation and lowering global temperatures. The amount of sulfur-rich gases released seems to be more important than the general size of the eruption. It can take years for these particles to settle out of the atmosphere. Chemicals released in eruptions can interact with human-made chlorofluorocarbons to Close view of Mesa Falls ash-flow tuff and underlying fallout deteriorate the ozone layer, which increases ash exposed in a quarry near Ashton, . Courtesy of solar radiation. Luckily, these particles settle out US Geological Survey of the stratosphere in just a few years. While For example, while the Eyjafjallajökull eruption eruptions can enhance global warming by adding in Iceland in April 2010 released approximately carbon dioxide (CO2) to the atmosphere, human 0.15 million tons of CO2 each day, the reduction activities far outweigh any effects from any of air travel over Europe caused by the ash cloud eruption in human history. saved an estimated 1.3–2.8 million tons of CO2 FOSS Next Generation during that time. Yellowstone National Park—Page 5 of 8 © The Regents of the University of California Version date November 20, 2018 Can be duplicated for classroom or workshop use. What if there were a major Yellowstone 1980: Mount St. Helens blast kills 57 people and eruption today? causes $3 billion in damage. • The park and surrounding areas would be 1991: Pinatubo eruption in the Philippines obliterated. expells 20-25 km3 of ash. Scientists are able to • Heavy ash rains would bury large areas of closely study the atmospheric effects. More than the United States, collapsing buildings and half a million people are safely evacuated, due to increased understanding of volcanic behavior. devastating livestock, wildlife, croplands, and km3 erupted

forests. 3000 • All communication and transportation systems would be useless until the ash cleared. 2500

• Ash would create a volcanic winter that could 2000 last for years and influence the climate, causing massive extinctions, human famine, and disease. 1500

Scientists at Yellowstone Volcano Observatory 1000 (YVO) are constantly monitoring hydrothermal systems, earthquakes, and even the shape of the 500 magma chamber. This allows YVO to warn the public of potential hazards. While evidence 0 Toba Vesuvius Tambora Krakatau Pinatubo Kilgore Tuff Lava Creek shows that there will be future volcanic activity Blacktail Tuff Mesa Falls Tuff Mt. St. Helens EyjaMallajökull Nevado del Ruiz in Yellowstone, the probability of a large caldera- Bruneau‐Jarbidge Huckleberry Ridge forming eruption within the next few thousand Yellowstone has produced two of the world’s most cataclysmic explosive eruptions in the last 2 million years. The graph shows some of the most significant eruptions in years is exceedingly low. Earth’s history, in order of the volume of ash released. Events 66 mya: Deccan flood in Western India release 20.8 million cubic kilometers (km3) of gases, possibly contributing to the extinction of dinosaurs after a meteorite strike. 2.1 mya: Huckleberry Ridge eruption in Yellowstone, expelling 2,500 km3 of ash, is considered greater than 100,000 atomic bombs. 1.3 mya: from the eruption in Yellowstone that expells 280 km3 of ash. Scientists evaluate natural-hazard levels by combining their knowledge of the 640,000 years ago: Tuff from the eruption in frequency and severity of hazardous events. In the Yellowstone region, hydrother- Yellowstone that expells 1,000 km3 of ash. mal and earthquakes can occur several times a century. Lava flows and small volcanic eruptions occur only rarely—none in the past 70,000 years. Massive 70,000-150,000 years ago: Rhyolitic lava flows caldera-forming eruptions, though the most potentially devastating of Yellowstone’s occur all over Yellowstone. hazards, are extremely rare. Only three have occurred in the past several million years. 74,000 years ago: Toba eruption in Indonesia Courtesy US Geological Survey. expells 2,800 km3 of ash that blocks up to 90 percent of sunlight and causes temperatures to Vocabulary drop 1-3°C. Some scientists believe this started ash fall ash layers created from an eruption. the last ice age, and other evidence suggests that effusive eruptions gentle, continuous our human ancestors were almost wiped out. outpouring of lava 15,000-2,000 years ago: Formation of Craters explosive eruptions caldera-forming eruptions of the Moon, the largest lava field of the Snake that cause immediate destruction River Plain. mya millions of years ago 1815: Tambora eruption in Indonesia creates a caldera 6.5 km wide. Global temperatures drop supereruption eruptions greater than 1,000 3°C, creating “the year without summer.” Due to cubic kilometers. starvation from lost croplands, 117,000 people die. tuff type of rock made from volcanic ash FOSS Next Generation Yellowstone National Park—Page 6 of 8 © The Regents of the University of California Version date November 20, 2018 Can be duplicated for classroom or workshop use. Geoscenario Resources—Yellowstone Hotspot: Renewable-Energy Consultant Task Now that you have explored as a team the general story of the Yellowstone Hotspot, it is time for each of you to dive into more specialized information. The renewable energy consultant focuses on geothermal energy—how it compares to other natural resources and the pros and cons of tapping such a resource. Add helpful details to your notes for Geoscenario Team Questions. Then work together and combine all the information to successfully present your story of the Yellowstone Hotspot. Questions for the Renewable-Energy Consultant to Consider • How does geothermal energy compare to other natural resources? • What are the pros and cons of tapping into geothermal energy in Yellowstone National Park? Information and water are injected back into reservoirs for The large magma chamber beneath Yellowstone efficiency and emission reduction. National Park superheats the surrounding rock • Geothermal heat pumps: Heat pumps do and underground water reservoirs. The US not require reservoirs and thus can be used Geological Survey estimates the average heat almost everywhere in the world. The pumps flow from Earth’s interior at Yellowstone to be 30 use the stable temperature of 10–16°C found times greater than the typical heat flow for the most places 3 m beneath Earth’s surface to surrounding areas. At Norris Geyser Basin, water control building temperatures above ground. temperatures were recorded as hot as 238°C at Geothermal heat pumps use 30-60 percent less just 330 meters (m) below the surface. electricity than traditional heating and cooling Geothermal energy uses Earth’s internal heat to systems. The electricity that powers the system derive usable energy to generate hot water, heat is used only to move heat, not to produce it. buildings, stabilize building temperatures, and create electricity. It is considered a renewable energy source because it is continuously replenished by Earth’s core heating system. Steam vents from a geothermal Naturally occurring areas for exploitation are power plant. called geothermal reservoirs. Most geothermal © iStockphoto/Rhoberazzi reservoirs in the United States are located in the western states and Hawaii. California currently offers the most opportunities to produce electricity from geothermal energy in the United States. Geothermal energy is most often used in these ways. • Direct use: Hot water from springs or reservoirs near the surface is used to heat buildings, water systems, sidewalks, or US geothermal greenhouses. resource potential, • Electricity-generated power plants: based on current Geothermal reservoirs superheat water, which technology, for seeking viable creates steam that is run through turbines to geothermal convert the thermal energy into electricity. reservoirs. Geothermal plants emit 97 percent less acid Courtesy US Department rain–causing pollutants than coal and natural of Energy gas power plants and a fraction of the carbon

dioxide (CO2) emissions. Much of the steam FOSS Next Generation Yellowstone National Park—Page 7 of 8 © The Regents of the University of California Version date November 20, 2018 Can be duplicated for classroom or workshop use. PROS AND CONS OF BUILDING A PLANT Pros Cons • Renewable energy source with minimal pollution • Can deplete flow of nearby geysers and hot springs • Most stable renewable resource (compared to wind • Many of our nation’s geothermal resources in wild or and solar) and much less destructive than building protected areas. dams for hydropower • Creates mineral-rich discharge water as waste, but • Good against our foreign dependence on oil and for most systems pump back into reservoirs. lowering CO2 emissions • Some products are sludges that require disposal in • Reduce acid rain–producing pollutants by 97 percent approved sites. compared to fossil fuel–burning power plants • Substantial costs to build the plants • Much more efficient systems for producing heat and • Often require large amount of space, making it electricity than converting fossil fuels difficult to access some potential reservoirs • Can incorporate geothermal heat pumps almost anywhere reducing energy for electrically controlling building temperature by 30–60 percent.

Events 40,000–9,000 years ago: Hot springs are used for bathing during the Paleolithic era. 300 BC: The oldest known spa is a stone pool on China’s Lisan Mountain. 1300s: The world’s oldest geothermal district Diagram of a geothermal heat pump for a house heating system starts in Chaudes-Aigues, France ©iStockphoto/Slavomir Valigursky (and is still successful). 1892: America’s first district heating system, in Vocabulary Boise, Idaho, is powered directly by geothermal geothermal thermal energy generated and energy. stored in the earth 1904: The first use of geothermal energy for heat flow the natural transfer of heat (thermal electric power is in Italy. energy) from one mass to a cooler mass. Late 1940s: The first direct-exchange, ground- renewable energy energy from natural source heat pump is created. resources (such as sunlight, wind, rain, tides, and 1960: Pacific Gas and Electric begins operation geothermal heat) that are naturally replenished of the first successful geothermal electric power plant in the United States at The Geysers in California.

FOSS Next Generation Yellowstone National Park—Page 8 of 8 © The Regents of the University of California Version date November 20, 2018 Can be duplicated for classroom or workshop use.