Yellowstone National Park
Yellowstone National Park (Arapaho: Henihco'oo' or HéetÃhco'oo) is a national park located primarily in the U.S. state of Wyoming, although it also extends into Montana and Idaho. It was established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872.Yellowstone, widely held to be the first national park in the world,is known for its wildlife and its many geothermal features, especially Old Faithful Geyser, one of the most popular features in the park It has many types of ecosystems, but the subalpine forest is dominant.
Native Americans have lived in the Yellowstone region for at least 11,000 years.The region was bypassed during the Lewis and Clark Expedition in the early 19th century. Aside from visits by mountain men during the early-to-mid-19th century, organized exploration did not begin until the late 1860s. The U.S. Army was commissioned to oversee the park just after its establishment. In 1917, administration of the park was transferred to the National Park Service, which had been created the previous year. Hundreds of structures have been built and are protected for their architectural and historical significance, and researchers have examined more than 1,000 archaeological sites.
Yellowstone National Park spans an area of 3,468.4 square miles (8,983 km2), comprising lakes, canyons, rivers and mountain ranges. Yellowstone Lake is one of the largest high-altitude lakes in North America and is centered over the Yellowstone Caldera, the largest supervolcano on the continent. The caldera is considered an active volcano. It has erupted with tremendous force several times in the last two million years. Half of the world's geothermal features are in Yellowstone, fueled by this ongoing volcanism. Lava flows and rocks from volcanic eruptions cover most of the land area of Yellowstone. The park is the centerpiece of the Greater Yellowstone Ecosystem, the largest remaining nearly-intact ecosystem in the Earth's northern temperate zone.
Hundreds of species of mammals, birds, fish and reptiles have been documented, including several that are either endangered or threatened. The vast forests and grasslands also include unique species of plants. Yellowstone Park is the largest and most famous megafauna location in the Continental United States. Grizzly bears, wolves, and free-ranging herds of bison and elk live in the park. The Yellowstone Park bison herd is the oldest and largest public bison herd in the United States. Forest fires occur in the park each year; in the large forest fires of 1988, nearly one third of the park was burnt. Yellowstone has numerous recreational opportunities, including hiking, camping, boating, fishing and sightseeing. Paved roads provide close access to the major geothermal areas as well as some of the lakes and waterfalls. During the winter, visitors often access the park by way of guided tours that use either snow coaches or snowmobiles.
History
The park is located at the headwaters of the Yellowstone River, from which it takes its historical name. Near the end of the 18th century, French trappers named the river "Roche Jaune", which is probably a translation of the Minnetaree name "Mi tsi a-da-zi" (Rock Yellow River). Later, American trappers rendered the French name in English as "Yellow Stone". Although it is commonly believed that the river was named for the yellow rocks seen in the Grand Canyon of the Yellowstone, the Native American name source is not clear.
The human history of the park begins at least 11,000 years ago when aboriginal Americans first began to hunt and fish in the region. During the construction of the post office in Gardiner, Montana, in the 1950s, an obsidian projectile point of Clovis origin was found that dated from approximately 11,000 years ago. These Paleo-Indians, of the Clovis culture, used the significant amounts of obsidian found in the park to make cutting tools and weapons. Arrowheads made of Yellowstone obsidian have been found as far away as the Mississippi Valley, indicating that a regular obsidian trade existed between local tribes and tribes farther east. By the time white explorers first entered the region during the Lewis and Clark Expedition in 1805, they encountered the Nez Perce, Crow, and Shoshone tribes. While passing through present day Montana, the expedition members were informed of the Yellowstone region to the south, but they did not investigate it.
In 1806, John Colter, a member of the Lewis and Clark Expedition, left to join a group of fur trappers. After splitting up with the other trappers in 1807, Colter passed through a portion of what later became the park, during the winter of 1807–1808. He observed at least one geothermal area in the northeastern section of the park, near Tower Fall. After surviving wounds he suffered in a battle with members of the Crow and Blackfoot tribes in 1809, he described a place of "fire and brimstone" that most people dismissed as delirium; the supposedly imaginary place was nicknamed "Colter's Hell". Over the next 40 years, numerous reports from mountain men and trappers told of boiling mud, steaming rivers, and petrified trees, yet most of these reports were believed at the time to be myth.
After an 1856 exploration, mountain man Jim Bridger (also believed to be the first or second European American to have seen the Great Salt Lake) reported observing boiling springs, spouting water, and a mountain of glass and yellow rock. These reports were largely ignored because Bridger was known for being a "spinner of yarns". In 1859, a U.S. Army Surveyor named Captain William F. Raynolds embarked on a two-year survey of the northern Rockies. After wintering in Wyoming, in May 1860, Raynolds and his party - which included naturalist Ferdinand Vandeveer Hayden and guide Jim Bridger - attempted to cross the Continental Divide over Two Ocean Plateau from the Wind River drainage in northwest Wyoming. Heavy spring snows prevented their passage, but had they been able to traverse the divide, the party would have been the first organized survey to enter the Yellowstone region.The American Civil War hampered further organized explorations until the late 1860s.
Ferdinand V. Hayden (1829 – 1887) American geologist who convinced Congress to make Yellowstone a National Park in 1872.
The first detailed expedition to the Yellowstone area was the Cook–Folsom–Peterson Expedition of 1869, which consisted of three privately funded explorers. The Folsom party followed the Yellowstone River to Yellowstone Lake.The members of the Folsom party kept a journal and based on the information it reported, a party of Montana residents organized the Washburn-Langford-Doane Expedition in 1870. It was headed by the surveyor-general of Montana Henry Washburn, and included Nathaniel P. Langford (who later became known as "National Park" Langford) and a U.S. Army detachment commanded by Lt. Gustavus Doane.
The expedition spent about a month exploring the region, collecting specimens and naming sites of interest. A Montana writer and lawyer named Cornelius Hedges, who had been a member of the Washburn expedition, proposed that the region should be set aside and protected as a national park; he wrote a number of detailed articles about his observations for the Helena Herald newspaper between 1870 and 1871. Hedges essentially restated comments made in October 1865 by acting Montana Territorial Governor Thomas Francis Meagher, who had previously commented that the region should be protected.Others made similar suggestions. In an 1871 letter from Jay Cooke to Ferdinand V. Hayden, Cooke wrote that his friend, Congressman William D. Kelley had also suggested "Congress pass a bill reserving the Great Geyser.
Geology of Yellowstone
Yellowstone National Park is a place rich in recent and ancient human, evolutionary, and geological history. Its spectacular features are shaped by the same processes happening almost everywhere else on the globe, and one spectacular process that rarely happens on Earth.
Layers Upon Layers
We'll approach Yellowstone geology the way we approach most geology, by describing the layers of rock that form it. The oldest rock in Yellowstone National Park is Precambrian in age, over 500 million years old. You can find some granites, but thanks to the multiple episodes of mountain building that begat the Rocky Mountains, a lot of these have been metamorphosed into gneisses and schists.
During the Palaeozoic Era (500 - 235 million years ago), Yellowstone National Park and most of the rest of the Western United States lay beneath or on the edge of a shallow sea. During this time, many of the sedimentary rocks of Yellowstone were deposited, most of them limestone, sandstone, and shale. The Mesozoic Era (235-65 million years ago) generally brought about more terrestrial environments, with sandstone and shale bearing river features. Some of these formations in the park have been found to contain dinosaur fossils. At the end of the late Cretaceous Period, 65million years ago, the first signs of Yellowstone's volatile volcanic nature can be found, which continues to manifest itself today.
Grand Canyons
Yellowstone has also been shaped by rivers and streams. The Grand Canyon of Yellowstone2, immortalised in paintings, photos and engravings, was cut solely by the Yellowstone River. It is roughly 20 miles long, and has two major waterfalls. Water plunges 109 feet over the Upper Falls, but thunders 308 feet over the Lower Falls. Rivers and streams also bring mineral-rich sediment down from the mountain, creating good soils on the floodplains. The Continental Divide, separating the Mississippi drainage basin from the Western United States, also runs through Yellowstone.
Rivers of Ice
Glaciers have been intermittently shaping Yellowstone National Park for the past two million years. The most recent glaciation began about 50,000 years ago, when snow piled up northeast of the Park on the high mountains of the Absaroka, in the Beartooth Wilderness area. Once the glaciers started moving, they ploughed through the park to converge over Yellowstone Lake, completely covering the Park and surrounding area in over a thousand feet of ice. The glaciers left their scars at the peak 25,000 years ago on the top of all but the highest mountains in the area, Mount Washburn and the highest ridges of the Absaroka Range.
When the deep-freeze finally broke 15,000 years ago, the ice had transformed Yellowstone. At the very end of the Ice Age, much of the glaciers' meltwater was trapped behind a giant ice dam, leaving the fertile lake deposits we see in Hayden Valley when it finally ceased to exist. Rivers of ice widened and scoured existing river valleys, and left behind fields dotted with granite boulders from faraway mountains3. Glacial ponds, striated hillsides4, chiselled peaks, and polished mountain faces all bear witness to the geological force of ice.
Glacial deposits are often affected by thermal features, particularly in the Norris Geyser Basin. Hot water from geysers and hot springs percolates through the deposits and alters them, forming minerals we don't expect to see at the surface. However, collecting is strictly forbidden without a permit in Yellowstone National Park. All mineral collectors must keep their hands to themselves.
Did you just feel the ground move?
Yellowstone National Park is home to a number of active fault systems, a fact with which an unlucky group of campers became acquainted on 17 August, 1959 at 11.37pm. At that moment, a 7.8 magnitude earthquake struck in West Yellowstone along the Hebgen Lake Fault. It shattered the surrounding rock with three major faults, displaced the stream Red Creek as much as 20 feet, and altered thermal features in other parts of the Park. It shook the reservoir above Madison Canyon so badly it sent a 20-feet-high wall of water into what was, at that point, a campground. Further down, 44 million cubic yards of solid rock, half of a 7600-feet-high mountain, fell into a valley at 174 miles per hour, smashing house-sized boulders into tents as campers slept, and sending hurricane force winds up the narrow valley. Stories abound of entire families being killed as they slept, and of children being orphaned because a house-sized boulder fell on their parents' tent six feet away. Luckily, the fallen mountain dammed the canyon, creating Earthquake Lake before the flood could reach further down the valley. 28 people are thought to have died in the quake and following landslide and flood, and are still buried beneath the rubble, so it is unlikely that the true death toll will ever be known.
Thermal Features
Geology is the main reason why Yellowstone was made into the world's first National Park. In particular, it earned that honour because of the thermal features that lie within its borders.
Yellowstone is literally a hotbed of geologic activity. The increased temperatures only a few miles beneath the surface superheat groundwater found naturally in the rock. This has the same effect as boiling a sealed bottle. The superheated liquid in the bottle has to find somewhere to escape, so it often blows the top off. In Yellowstone, the water escapes to the surface through existing cracks in the rock, giving the park the honour of having 90% of the world's thermal features.
Several things can happen to the superheated water at this point, depending on the shape of the crack and how much water is in it. If the crack opens all the way to the surface with no obstructions, the water will form a hot spring. The heat is released at the surface, and the water is allowed to recirculate back underground.
Thanks to the miles of rock the water has travelled through, hot springs are rich in minerals such as sulphur, which give them a distinct odour and technicolour hues that are nearly impossible to capture with a camera. These same minerals also support some of the most bizarre and primitive communities of microbes on Earth. Ancestors of these organisms that survive in boiling water left their traces in rocks over 3.5billion years old! They thrive in giant microbial mats in 70°C (160°F) water. When the water cools sufficiently, hot springs can form step-like rock features called terraces6, the most spectacular of which are the Terraces at Mammoth Hot Springs. Other notable hot springs in the park are Prismatic Spring (the largest), and Morning Glory Pool, which was sadly vandalised in the early days of the park, robbing it of the most spectacular of its colours. Visitors can still see debris in the pool.
Sometimes a hot spring provides a home for sulphide-reducing bacteria. These micro-organisms use the hydrogen sulphide, which gives the hot springs their characteristic odour, for energy, with the waste product being sulphuric acid. This eats into the rock of the hot spring, turning it to clay. Eventually, this clogs the plumbing, limiting the hot spring's water supply. However, the hot spring doesn't die, instead it becomes a mud pot. Mud pots are bubbling cauldrons of acidic mud. Gases that would normally boil away with the water of a hot spring escape through the viscous gunk, with a sound and a smell that reminds many of flatulence. The most famous mud pot is Artists' Paintpots, a colourful mass of boiling mud that reminds one of a mad artist that has eaten too many beans.
When a hot spring has a plumbing problem deeper in the rock, things get interesting. A constriction in the crack leading to the surface partially blocks the water, causing pressure to build, until it blows past the obstruction and rushes out into the atmosphere. This is known as a geyser. Geysers can erupt regularly, like Old Faithful, or sporadically, like the spectacular Steamboat Geyser which reaches 300-400 feet. Some have months or years between eruptions, while other erupt nearly every minute! Sometimes, the water supply for a geyser will run out. The geyser will disappear, leaving a calcium carbonate geyser cone as a tombstone.
The fourth major thermal feature in Yellowstone is the most common and the most puzzling to uninitiated tourists. Fumaroles, or steam vents, are essentially geysers that do not have enough water to erupt. Instead, they belch steam from a hole in the ground, smelling like sulphur and making a noise that the guidebook describes as thunder, but sounds to some like a giant toilet flushing. Steam vents are the hottest thermal features in Yellowstone, and are very easy to find.
Yellowstone's thermal features can be dangerously unpredictable. Thanks to thermal feature surprises, the National Park Service has had to move parking lots and tourist boardwalks. A new geyser or hot spring can open up at any moment, especially on the thin crispy crust known as sinter around existing thermal features. Hundreds of people have been injured or killed when they stepped off the boardwalk for a better picture of a thermal feature, only to have one open up under their feet.
Yellowstone Volcanism
Most visitors to the Park know there are different forces at work in Yellowstone the instant they see steam shooting from the ground, but exactly what is going on remains a mystery to many. Many leave with the understanding that Yellowstone is a volcanic caldera which is still quite active but tame, its heat powering the geysers. As usual, there is much, much more to the story.
Around 640,000 years ago, a few thousand miles away in what would become Ashfall, Nebraska, lay an environment similar to the African savannah. Elephants, rhinos, three-toed horses, and antelope-like sabre-tooth deer shared a waterhole, and were preyed upon by dire wolves. That went on until a cloud of volcanic dust buried the area in eight feet of ash. In the 1970s, scientists traced the composition of the ash back to the world's most famous National Park. This ash was from what is called a supervolcano. This brings up the image of a giant, cone-shaped mountain belching gooey lava and smoke for many people. However, a mountain large enough to cough out that much ash and leave a crater the size of Yellowstone would have had to have been several hundred miles in diameter. With all that we know about geology and physics, we know that individual mountains simply cannot get that large. However, as with most problems, a good hike sheds some light on some things, in particular, a 1,400-feet climb up Mount Washburn.
The view from Mount Washburn looking south reveals the bulk of Yellowstone National Park is a relatively flat, rolling plain edged by mountains. Large mountains, like the Grand Tetons to the south, the Absaroka Mountains to the east, and of course, Mount Washburn. What we know about geology tells us that mountains don't form naturally with a 37-mile gap in between them. This begs the question, what happened to the mountains that we should have seen there?
In short, they blew up, then collapsed within a matter of weeks, slumping into Yellowstone, spewing out 240 cubic miles of debris and leaving a 30km by 50km volcanic caldera. Compare this to the Minoan Eruption of Santorini, or Tambora, one of the most massive volcanic events in recorded history.
This is not the first time this has happened. There have been at least three supervolcano eruptions recorded in Yellowstone's geologic record. The most recent blast 640,000 years ago is known as the Lava Creek event. The Mesa Falls eruption occurred roughly 1.3 million years ago, preceded by massive lava flows that you can still see on the edges of the park. The Huckleberry Ridge eruption 2.1 million years ago was possibly the most massive volcanic event in the history of the Earth for which there is rock record, based on the extent of the ashfall all over the world.
The average time between eruptions? 600,000 years.
Hot Spot
What caused the volcano to form in the first place? Yellowstone is nowhere near any tectonic plate boundaries, so it shouldn't even be there, surely?
Not exactly. Yellowstone is right above what is termed a mantle hot spot. Scientists theorise that 25 million years ago, the molten portion of the Earth's core ejected a mass of hot material directly below Yellowstone. Ten million years ago, that plume reached the surface of the earth, and spread out to form a shape much like a martini glass. These are not entirely uncommon as there are approximately 40 active hotspots on Earth today, nearly all of them in oceans. The Yellowstone Hotspot had the power to burn through an entire continent. Molten rock exists under the Park today anywhere from three to eight miles below the surface by geophysical estimates. Compared to the rest of the planet, parkgoers are truly skating on thin ice.
Wildlife in Yellowstone
Yellowstone is home to abundant and varied wildlife, unlike anywhere else in America. Nearly all of the wildlife species that inhabited the park when it was first explored over 100 years ago survive today. Early morning and evening hours are the best times to view wildlife.
Badgers, like the one pictured are common at lower elevations and can be spotted in the northern range of Yellowstone park. The badgers favorite food in Yellowstone are ground squirrels, and we often see badgers digging in the ground in search of a meal. Patience, and a lot of sitting and looking are the keys to spotting badgers.
Uinta Ground Squirrel's are a popular and favorite food item for many of Yellowstone's predators including coyote's, badgers, and hawks.
These small rodents can be found throughout the park, however they do hibernate during winter months.
Bison are very unpredictable and one of the more dangerous animals in Yellowstone park. Visitors often crowd around or get too close to bison and some have been gored, injured or even killed over the years. Real examples of visitors getting too close to bison, and the results--View bison goring video's.
Bison are common in Yellowstone park and can be viewed in many locations during most of the year. However, if you visit Yellowstone in August your best chance of viewing them will be at Hayden Valley. Bison travel from all over Yellowstone park in late July to Hayden Valley for their annual mating season. Plan on viewing them in early morning while they are located in Hayden Valley. During mid-day to early evening the traffic is terrible and you can expect to be caught in a 3 or 4 mile long traffic jam for sometimes hours. Avoid the Canyon area from noon till dusk in August or late July. Bison can also be viewed in the Lamar Valley each month of year.
are also considered dangerous, but few visitors in Yellowstone Park get the chance to view them today. For the most part, grizzly bears avoid the roads and heavy use areas that are occupied by people. Research has found that the average adult grizzly bear will avoid an active road up to 2.4 miles.
During spring and mid summer, a few visitors do get lucky and have the opportunity to see a grizzly bear. In early spring (May and June) bears can be viewed just about anywhere in the park. In late summer (Aug.) visitors report seeing grizzly bears at Canyon and Mount Washburn.
Elk are common throughout Yellowstone Park. During September, bull elk gather herds of cows for their annual mating season and the large bulls can be heard throughout the day bugling. Bull elk can be very dangerous during this period. Keep your distance.
Bald eagles, are more commonly found during the winter months in Yellowstone park. The eagles migrate down from Canada and Alaska during the early winter and feed on animals that have died here in the park. They are also commonly found feeding on wolf kills during the winter months up in the northern range of the park. They then migrate back home in early spring where they feed on the spawning salmon.
Note: Starting in 1999 we have observed more bald eagles during the summer months in Yellowstone park. One pair in particular have nested and given birth along the Madison River between Madison Junction and the entrance at West Yellowstone Montana. Due to high traffic and stress levels, the park service has had to place no stopping, no walking, no parking regulations 50 yards on either side of this popular nest, along with a slower.
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Yellowstone National Park (Arapaho: Henihco'oo' or HéetÃhco'oo) is a national park located primarily in the U.S. state of Wyoming, although it also extends into Montana and Idaho. It was established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872.Yellowstone, widely held to be the first national park in the world,is known for its wildlife and its many geothermal features, especially Old Faithful Geyser, one of the most popular features in the park It has many types of ecosystems, but the subalpine forest is dominant.
Native Americans have lived in the Yellowstone region for at least 11,000 years.The region was bypassed during the Lewis and Clark Expedition in the early 19th century. Aside from visits by mountain men during the early-to-mid-19th century, organized exploration did not begin until the late 1860s. The U.S. Army was commissioned to oversee the park just after its establishment. In 1917, administration of the park was transferred to the National Park Service, which had been created the previous year. Hundreds of structures have been built and are protected for their architectural and historical significance, and researchers have examined more than 1,000 archaeological sites.
Yellowstone National Park spans an area of 3,468.4 square miles (8,983 km2), comprising lakes, canyons, rivers and mountain ranges. Yellowstone Lake is one of the largest high-altitude lakes in North America and is centered over the Yellowstone Caldera, the largest supervolcano on the continent. The caldera is considered an active volcano. It has erupted with tremendous force several times in the last two million years. Half of the world's geothermal features are in Yellowstone, fueled by this ongoing volcanism. Lava flows and rocks from volcanic eruptions cover most of the land area of Yellowstone. The park is the centerpiece of the Greater Yellowstone Ecosystem, the largest remaining nearly-intact ecosystem in the Earth's northern temperate zone.
Hundreds of species of mammals, birds, fish and reptiles have been documented, including several that are either endangered or threatened. The vast forests and grasslands also include unique species of plants. Yellowstone Park is the largest and most famous megafauna location in the Continental United States. Grizzly bears, wolves, and free-ranging herds of bison and elk live in the park. The Yellowstone Park bison herd is the oldest and largest public bison herd in the United States. Forest fires occur in the park each year; in the large forest fires of 1988, nearly one third of the park was burnt. Yellowstone has numerous recreational opportunities, including hiking, camping, boating, fishing and sightseeing. Paved roads provide close access to the major geothermal areas as well as some of the lakes and waterfalls. During the winter, visitors often access the park by way of guided tours that use either snow coaches or snowmobiles.
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History
The park is located at the headwaters of the Yellowstone River, from which it takes its historical name. Near the end of the 18th century, French trappers named the river "Roche Jaune", which is probably a translation of the Minnetaree name "Mi tsi a-da-zi" (Rock Yellow River). Later, American trappers rendered the French name in English as "Yellow Stone". Although it is commonly believed that the river was named for the yellow rocks seen in the Grand Canyon of the Yellowstone, the Native American name source is not clear.
The human history of the park begins at least 11,000 years ago when aboriginal Americans first began to hunt and fish in the region. During the construction of the post office in Gardiner, Montana, in the 1950s, an obsidian projectile point of Clovis origin was found that dated from approximately 11,000 years ago. These Paleo-Indians, of the Clovis culture, used the significant amounts of obsidian found in the park to make cutting tools and weapons. Arrowheads made of Yellowstone obsidian have been found as far away as the Mississippi Valley, indicating that a regular obsidian trade existed between local tribes and tribes farther east. By the time white explorers first entered the region during the Lewis and Clark Expedition in 1805, they encountered the Nez Perce, Crow, and Shoshone tribes. While passing through present day Montana, the expedition members were informed of the Yellowstone region to the south, but they did not investigate it.
In 1806, John Colter, a member of the Lewis and Clark Expedition, left to join a group of fur trappers. After splitting up with the other trappers in 1807, Colter passed through a portion of what later became the park, during the winter of 1807–1808. He observed at least one geothermal area in the northeastern section of the park, near Tower Fall. After surviving wounds he suffered in a battle with members of the Crow and Blackfoot tribes in 1809, he described a place of "fire and brimstone" that most people dismissed as delirium; the supposedly imaginary place was nicknamed "Colter's Hell". Over the next 40 years, numerous reports from mountain men and trappers told of boiling mud, steaming rivers, and petrified trees, yet most of these reports were believed at the time to be myth.
After an 1856 exploration, mountain man Jim Bridger (also believed to be the first or second European American to have seen the Great Salt Lake) reported observing boiling springs, spouting water, and a mountain of glass and yellow rock. These reports were largely ignored because Bridger was known for being a "spinner of yarns". In 1859, a U.S. Army Surveyor named Captain William F. Raynolds embarked on a two-year survey of the northern Rockies. After wintering in Wyoming, in May 1860, Raynolds and his party - which included naturalist Ferdinand Vandeveer Hayden and guide Jim Bridger - attempted to cross the Continental Divide over Two Ocean Plateau from the Wind River drainage in northwest Wyoming. Heavy spring snows prevented their passage, but had they been able to traverse the divide, the party would have been the first organized survey to enter the Yellowstone region.The American Civil War hampered further organized explorations until the late 1860s.
Ferdinand V. Hayden (1829 – 1887) American geologist who convinced Congress to make Yellowstone a National Park in 1872.
The first detailed expedition to the Yellowstone area was the Cook–Folsom–Peterson Expedition of 1869, which consisted of three privately funded explorers. The Folsom party followed the Yellowstone River to Yellowstone Lake.The members of the Folsom party kept a journal and based on the information it reported, a party of Montana residents organized the Washburn-Langford-Doane Expedition in 1870. It was headed by the surveyor-general of Montana Henry Washburn, and included Nathaniel P. Langford (who later became known as "National Park" Langford) and a U.S. Army detachment commanded by Lt. Gustavus Doane.
The expedition spent about a month exploring the region, collecting specimens and naming sites of interest. A Montana writer and lawyer named Cornelius Hedges, who had been a member of the Washburn expedition, proposed that the region should be set aside and protected as a national park; he wrote a number of detailed articles about his observations for the Helena Herald newspaper between 1870 and 1871. Hedges essentially restated comments made in October 1865 by acting Montana Territorial Governor Thomas Francis Meagher, who had previously commented that the region should be protected.Others made similar suggestions. In an 1871 letter from Jay Cooke to Ferdinand V. Hayden, Cooke wrote that his friend, Congressman William D. Kelley had also suggested "Congress pass a bill reserving the Great Geyser.
Geology of Yellowstone
Yellowstone National Park is a place rich in recent and ancient human, evolutionary, and geological history. Its spectacular features are shaped by the same processes happening almost everywhere else on the globe, and one spectacular process that rarely happens on Earth.
Layers Upon Layers
We'll approach Yellowstone geology the way we approach most geology, by describing the layers of rock that form it. The oldest rock in Yellowstone National Park is Precambrian in age, over 500 million years old. You can find some granites, but thanks to the multiple episodes of mountain building that begat the Rocky Mountains, a lot of these have been metamorphosed into gneisses and schists.
During the Palaeozoic Era (500 - 235 million years ago), Yellowstone National Park and most of the rest of the Western United States lay beneath or on the edge of a shallow sea. During this time, many of the sedimentary rocks of Yellowstone were deposited, most of them limestone, sandstone, and shale. The Mesozoic Era (235-65 million years ago) generally brought about more terrestrial environments, with sandstone and shale bearing river features. Some of these formations in the park have been found to contain dinosaur fossils. At the end of the late Cretaceous Period, 65million years ago, the first signs of Yellowstone's volatile volcanic nature can be found, which continues to manifest itself today.
Grand Canyons
Yellowstone has also been shaped by rivers and streams. The Grand Canyon of Yellowstone2, immortalised in paintings, photos and engravings, was cut solely by the Yellowstone River. It is roughly 20 miles long, and has two major waterfalls. Water plunges 109 feet over the Upper Falls, but thunders 308 feet over the Lower Falls. Rivers and streams also bring mineral-rich sediment down from the mountain, creating good soils on the floodplains. The Continental Divide, separating the Mississippi drainage basin from the Western United States, also runs through Yellowstone.
Rivers of Ice
Glaciers have been intermittently shaping Yellowstone National Park for the past two million years. The most recent glaciation began about 50,000 years ago, when snow piled up northeast of the Park on the high mountains of the Absaroka, in the Beartooth Wilderness area. Once the glaciers started moving, they ploughed through the park to converge over Yellowstone Lake, completely covering the Park and surrounding area in over a thousand feet of ice. The glaciers left their scars at the peak 25,000 years ago on the top of all but the highest mountains in the area, Mount Washburn and the highest ridges of the Absaroka Range.
When the deep-freeze finally broke 15,000 years ago, the ice had transformed Yellowstone. At the very end of the Ice Age, much of the glaciers' meltwater was trapped behind a giant ice dam, leaving the fertile lake deposits we see in Hayden Valley when it finally ceased to exist. Rivers of ice widened and scoured existing river valleys, and left behind fields dotted with granite boulders from faraway mountains3. Glacial ponds, striated hillsides4, chiselled peaks, and polished mountain faces all bear witness to the geological force of ice.
Glacial deposits are often affected by thermal features, particularly in the Norris Geyser Basin. Hot water from geysers and hot springs percolates through the deposits and alters them, forming minerals we don't expect to see at the surface. However, collecting is strictly forbidden without a permit in Yellowstone National Park. All mineral collectors must keep their hands to themselves.
Did you just feel the ground move?
Yellowstone National Park is home to a number of active fault systems, a fact with which an unlucky group of campers became acquainted on 17 August, 1959 at 11.37pm. At that moment, a 7.8 magnitude earthquake struck in West Yellowstone along the Hebgen Lake Fault. It shattered the surrounding rock with three major faults, displaced the stream Red Creek as much as 20 feet, and altered thermal features in other parts of the Park. It shook the reservoir above Madison Canyon so badly it sent a 20-feet-high wall of water into what was, at that point, a campground. Further down, 44 million cubic yards of solid rock, half of a 7600-feet-high mountain, fell into a valley at 174 miles per hour, smashing house-sized boulders into tents as campers slept, and sending hurricane force winds up the narrow valley. Stories abound of entire families being killed as they slept, and of children being orphaned because a house-sized boulder fell on their parents' tent six feet away. Luckily, the fallen mountain dammed the canyon, creating Earthquake Lake before the flood could reach further down the valley. 28 people are thought to have died in the quake and following landslide and flood, and are still buried beneath the rubble, so it is unlikely that the true death toll will ever be known.
Thermal Features
Geology is the main reason why Yellowstone was made into the world's first National Park. In particular, it earned that honour because of the thermal features that lie within its borders.
Yellowstone is literally a hotbed of geologic activity. The increased temperatures only a few miles beneath the surface superheat groundwater found naturally in the rock. This has the same effect as boiling a sealed bottle. The superheated liquid in the bottle has to find somewhere to escape, so it often blows the top off. In Yellowstone, the water escapes to the surface through existing cracks in the rock, giving the park the honour of having 90% of the world's thermal features.
Several things can happen to the superheated water at this point, depending on the shape of the crack and how much water is in it. If the crack opens all the way to the surface with no obstructions, the water will form a hot spring. The heat is released at the surface, and the water is allowed to recirculate back underground.
Thanks to the miles of rock the water has travelled through, hot springs are rich in minerals such as sulphur, which give them a distinct odour and technicolour hues that are nearly impossible to capture with a camera. These same minerals also support some of the most bizarre and primitive communities of microbes on Earth. Ancestors of these organisms that survive in boiling water left their traces in rocks over 3.5billion years old! They thrive in giant microbial mats in 70°C (160°F) water. When the water cools sufficiently, hot springs can form step-like rock features called terraces6, the most spectacular of which are the Terraces at Mammoth Hot Springs. Other notable hot springs in the park are Prismatic Spring (the largest), and Morning Glory Pool, which was sadly vandalised in the early days of the park, robbing it of the most spectacular of its colours. Visitors can still see debris in the pool.
Sometimes a hot spring provides a home for sulphide-reducing bacteria. These micro-organisms use the hydrogen sulphide, which gives the hot springs their characteristic odour, for energy, with the waste product being sulphuric acid. This eats into the rock of the hot spring, turning it to clay. Eventually, this clogs the plumbing, limiting the hot spring's water supply. However, the hot spring doesn't die, instead it becomes a mud pot. Mud pots are bubbling cauldrons of acidic mud. Gases that would normally boil away with the water of a hot spring escape through the viscous gunk, with a sound and a smell that reminds many of flatulence. The most famous mud pot is Artists' Paintpots, a colourful mass of boiling mud that reminds one of a mad artist that has eaten too many beans.
When a hot spring has a plumbing problem deeper in the rock, things get interesting. A constriction in the crack leading to the surface partially blocks the water, causing pressure to build, until it blows past the obstruction and rushes out into the atmosphere. This is known as a geyser. Geysers can erupt regularly, like Old Faithful, or sporadically, like the spectacular Steamboat Geyser which reaches 300-400 feet. Some have months or years between eruptions, while other erupt nearly every minute! Sometimes, the water supply for a geyser will run out. The geyser will disappear, leaving a calcium carbonate geyser cone as a tombstone.
The fourth major thermal feature in Yellowstone is the most common and the most puzzling to uninitiated tourists. Fumaroles, or steam vents, are essentially geysers that do not have enough water to erupt. Instead, they belch steam from a hole in the ground, smelling like sulphur and making a noise that the guidebook describes as thunder, but sounds to some like a giant toilet flushing. Steam vents are the hottest thermal features in Yellowstone, and are very easy to find.
Yellowstone's thermal features can be dangerously unpredictable. Thanks to thermal feature surprises, the National Park Service has had to move parking lots and tourist boardwalks. A new geyser or hot spring can open up at any moment, especially on the thin crispy crust known as sinter around existing thermal features. Hundreds of people have been injured or killed when they stepped off the boardwalk for a better picture of a thermal feature, only to have one open up under their feet.
Yellowstone Volcanism
Most visitors to the Park know there are different forces at work in Yellowstone the instant they see steam shooting from the ground, but exactly what is going on remains a mystery to many. Many leave with the understanding that Yellowstone is a volcanic caldera which is still quite active but tame, its heat powering the geysers. As usual, there is much, much more to the story.
Around 640,000 years ago, a few thousand miles away in what would become Ashfall, Nebraska, lay an environment similar to the African savannah. Elephants, rhinos, three-toed horses, and antelope-like sabre-tooth deer shared a waterhole, and were preyed upon by dire wolves. That went on until a cloud of volcanic dust buried the area in eight feet of ash. In the 1970s, scientists traced the composition of the ash back to the world's most famous National Park. This ash was from what is called a supervolcano. This brings up the image of a giant, cone-shaped mountain belching gooey lava and smoke for many people. However, a mountain large enough to cough out that much ash and leave a crater the size of Yellowstone would have had to have been several hundred miles in diameter. With all that we know about geology and physics, we know that individual mountains simply cannot get that large. However, as with most problems, a good hike sheds some light on some things, in particular, a 1,400-feet climb up Mount Washburn.
The view from Mount Washburn looking south reveals the bulk of Yellowstone National Park is a relatively flat, rolling plain edged by mountains. Large mountains, like the Grand Tetons to the south, the Absaroka Mountains to the east, and of course, Mount Washburn. What we know about geology tells us that mountains don't form naturally with a 37-mile gap in between them. This begs the question, what happened to the mountains that we should have seen there?
In short, they blew up, then collapsed within a matter of weeks, slumping into Yellowstone, spewing out 240 cubic miles of debris and leaving a 30km by 50km volcanic caldera. Compare this to the Minoan Eruption of Santorini, or Tambora, one of the most massive volcanic events in recorded history.
This is not the first time this has happened. There have been at least three supervolcano eruptions recorded in Yellowstone's geologic record. The most recent blast 640,000 years ago is known as the Lava Creek event. The Mesa Falls eruption occurred roughly 1.3 million years ago, preceded by massive lava flows that you can still see on the edges of the park. The Huckleberry Ridge eruption 2.1 million years ago was possibly the most massive volcanic event in the history of the Earth for which there is rock record, based on the extent of the ashfall all over the world.
The average time between eruptions? 600,000 years.
Hot Spot
What caused the volcano to form in the first place? Yellowstone is nowhere near any tectonic plate boundaries, so it shouldn't even be there, surely?
Not exactly. Yellowstone is right above what is termed a mantle hot spot. Scientists theorise that 25 million years ago, the molten portion of the Earth's core ejected a mass of hot material directly below Yellowstone. Ten million years ago, that plume reached the surface of the earth, and spread out to form a shape much like a martini glass. These are not entirely uncommon as there are approximately 40 active hotspots on Earth today, nearly all of them in oceans. The Yellowstone Hotspot had the power to burn through an entire continent. Molten rock exists under the Park today anywhere from three to eight miles below the surface by geophysical estimates. Compared to the rest of the planet, parkgoers are truly skating on thin ice.
Wildlife in Yellowstone
Yellowstone is home to abundant and varied wildlife, unlike anywhere else in America. Nearly all of the wildlife species that inhabited the park when it was first explored over 100 years ago survive today. Early morning and evening hours are the best times to view wildlife.
Badgers, like the one pictured are common at lower elevations and can be spotted in the northern range of Yellowstone park. The badgers favorite food in Yellowstone are ground squirrels, and we often see badgers digging in the ground in search of a meal. Patience, and a lot of sitting and looking are the keys to spotting badgers. Uinta Ground Squirrel's are a popular and favorite food item for many of Yellowstone's predators including coyote's, badgers, and hawks. These small rodents can be found throughout the park, however they do hibernate during winter months.
Bison are very unpredictable and one of the more dangerous animals in Yellowstone park. Visitors often crowd around or get too close to bison and some have been gored, injured or even killed over the years. Real examples of visitors getting too close to bison, and the results--View bison goring video's.
Bison are common in Yellowstone park and can be viewed in many locations during most of the year. However, if you visit Yellowstone in August your best chance of viewing them will be at Hayden Valley. Bison travel from all over Yellowstone park in late July to Hayden Valley for their annual mating season. Plan on viewing them in early morning while they are located in Hayden Valley. During mid-day to early evening the traffic is terrible and you can expect to be caught in a 3 or 4 mile long traffic jam for sometimes hours. Avoid the Canyon area from noon till dusk in August or late July. Bison can also be viewed in the Lamar Valley each month of year.are also considered dangerous, but few visitors in Yellowstone Park get the chance to view them today. For the most part, grizzly bears avoid the roads and heavy use areas that are occupied by people. Research has found that the average adult grizzly bear will avoid an active road up to 2.4 miles. During spring and mid summer, a few visitors do get lucky and have the opportunity to see a grizzly bear. In early spring (May and June) bears can be viewed just about anywhere in the park. In late summer (Aug.) visitors report seeing grizzly bears at Canyon and Mount Washburn.
Elk are common throughout Yellowstone Park. During September, bull elk gather herds of cows for their annual mating season and the large bulls can be heard throughout the day bugling. Bull elk can be very dangerous during this period. Keep your distance. Bald eagles, are more commonly found during the winter months in Yellowstone park. The eagles migrate down from Canada and Alaska during the early winter and feed on animals that have died here in the park. They are also commonly found feeding on wolf kills during the winter months up in the northern range of the park. They then migrate back home in early spring where they feed on the spawning salmon. Note: Starting in 1999 we have observed more bald eagles during the summer months in Yellowstone park. One pair in particular have nested and given birth along the Madison River between Madison Junction and the entrance at West Yellowstone Montana. Due to high traffic and stress levels, the park service has had to place no stopping, no walking, no parking regulations 50 yards on either side of this popular nest, along with a slower.
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