About 34 million years ago, just off of what was the former coastline, two massive tectonic plates, the North American Plate and the Juan de Fuca Plate, were sent into a collision that would literally shape the Olympic mountains.
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The edifice of modern Mount Rainier assembled over the last half million years by the accumulation of hundreds individual lava flows, but an ancestral Mount Rainier stood in the same place from 1 to 2 million years ago. Before this, magmas both erupted and accumulated beneath the surface.
Mount Rainier has been active for the last 500,000 years; so the 2,200–year interval since the last known lava eruption is less than half a percent of the lifespan of the volcano. Summit and crater at the top of Mount Rainier, Washington.
A subduction zone is an area where one continental plate is being forced underneath another into the earth's mantel. Mount Rainier experiences about 20 small earthquakes a year, making it the second most seismically active volcano in the northern Cascade Range after Mount St. Helens. Seismicity is the study of earthquakes.
Mount Olympus Mountains are one of Olympic National Park’s most prominent geologic features, including Mt. Olympus, the tallest of the Olympic range. This giant reaches 7, 979 feet high at its summit. The Olympic Mountains are still being uplifted as the plates continue to converge.
Olympic Olympic National Park Geology of the Olympic Peninsula Three Stones, One Story Examining the Ages of Olympic S itting on the cobbly bank of the Elwha River, I drink
Olympic boasts diversity around every turn. Every layer of Olympic has an ecosystem that hosts unique features, plants, animals, geology, and history.
Ranking of the top 8 things to do in Olympic National Park. Travelers favorites include #1 Hoh Rain Forest, #2 Hurricane Ridge and more.
Olympic National Park. Located in the north-west of Washington State, Olympic National Park is renowned for the diversity of its ecosystems. Glacier-clad peaks interspersed with extensive alpine meadows are surrounded by an extensive old growth forest, among which is the best example of intact and protected temperate rainforest in the Pacific Northwest.
The coast of the Olympic Peninsula is particularly famous for some of this distinct geology, the history the rock preserves, and the incredible views they create today .
The Olympic Mountains were born in the sea. The basalts and sedimentary rocks that form the mass of these peaks were laid down 18 to 57 million years ago offshore, then uplifted, bent, folded and eroded into the rugged peaks you see today. Off the coast of the Olympic Peninsula, a dramatic story of epic proportions is slowly, yet steadily, ...
These towers of rock that make the peninsula coastline so famous define the views from beaches such as Ruby Beach, Ozette Beach, Shi Shi Beach, Rialto, La Push, and First, Second and Third Beach. Not only shrouded in salty water, but in history and mystery as well, the geology behind these majestic rock outcroppings lies just as much in what we see today as it does in what is no longer there.#N#The jagged sea stacks are a part of the Hoh Rock Assemblage. Long ago, this “Rock Assemblage” would have resembled a sort of geologic chocolate chip cookie dough. Throughout several millennia, there have been a great variety of rock types in the area. The dense volcanic and marine sedimentary rocks would be the chocolate chips amidst the cookie batter of the softer mudstone. At that time, the high cliffs now seen above the beach were sitting at sea level. The driving power of the ocean waves pummeled and weakened the mudstone, washing it away, but the sturdy volcanic chocolate chips remained. The cliffs rose with the same tectonic forces that rose the mountains of the peninsula, and alongside them rose the same volcanic outcroppings that were left behind.
Subduction is just the beginning of the monumental geologic story that is the Washington Peninsula. The mountains of today can be enjoyed from many viewpoints, but are changing each day. Over the course of millions of years, the immense weight of settling sand, mud, and debris on the ocean floor hardened into sedimentary rock. As the two tectonic plates of the area crash together, the Juan de Fuca Plate which holds the ocean and the Olympic Peninsula, is forced downward underneath the land-bearing North American Plate. However, not all of the crust on the oceanic plate makes its way further underground. Much of the built-up sedimentary rock on top of the tectonic plate continues to crumple against the landmass of North America and fold upwards out of the water, rising from the depths as time goes on.
Glaciers will have a blue hue to them because longer wavelengths of light, like the reds, are absorbed quickly into ice and snow, whereas shorter wavelengths, however, like the blues, are spread throughout . Crevasses, or large cracks and gaps, can be seen in glaciers. These are evidence of glaciers shifting and moving.
Moraines are piles of sediment that build up after being deposited or moved from the melting of a glacier. Typically, they are on the boundaries of a glacier, like at the edge (a lateral moraine) or at the end (a terminal moraine). Lakes and ponds can be created by glacial melt.
Lakes and Rivers. Water has directed and been directed in turn by the geologic processes of Olympic National Park that are highlighted below. Each water feature is bound in shape and flow by its geologic past.
Mount Rainier has been active for the last 500,000 years; so the 2,200–year interval since the last known lava eruption is less than half a percent of the lifespan of the volcano. Summit and crater at the top of Mount Rainier, Washington. (Credit: Mullineaux, Don. Public domain.)
Parts of Rainier also sit upon three older formations of volcanic rocks and associated sediments: Fife's Peak (26 to 22 Ma ), Stevens Ridge (26 Ma), and Ohanapecosh (36 to 28 Ma). About 40 million years ago, much of what is now western Washington lay beneath the sea, and widespread volcanism began due to the process of subduction off the margin ...
Public domain.) Mount Rainier is chiefly made of andesite and some dacite lava flows and has erupted sizeable amounts of pumice throughout its history, though not as voluminously or as frequently as Mount St. Helens. Pyroclastic flows are a relatively minor component of Mount Rainier's eruptive products, and lava domes are almost unknown ...
The edifice of modern Mount Rainier assembled over the last half million years by the accumulation of hundreds individual lava flows, but an ancestral Mount Rainier stood in the same place from 1 to 2 million years ago. Before this, magmas both erupted and accumulated beneath the surface. Some of this magma solidified as ...
Volcanism occurs at Mount Rainier and other Cascades arc volcanoes because of the subduction of the Juan de Fuca Plate off the western coast of North America. Mount Rainier is not the first volcano to have grown in its present location.
(Credit: Topinka, Lyn. Public domain.) Mount Rainier is an active volcano of the Cascade Range in Washington State, 50-70 km (30-44 mi) southeast of the Seattle–Tacoma metropolitan area.
Pyroclastic flows are a relatively minor component of Mount Rainier's eruptive products, and lava domes are almost unknown because itsandesitic magmas are more fluid than the stickier dacite magmas of Mount St. Helens.
The science plan was published in Mount Rainier Active Cascade Volcano and is available in the park library. Several studies related to geologic hazards are being conducted by the USGS, other federal and state agencies, and academic institutions.
The Decade Volcano initiative is part of a United Nations program aimed at better utilizing science and emergency management to reduce the severity of natural disasters.
Mount Rainier is an episodically active composite volcano, also called a stratovolcano. Volcanic activity began between one half and one million years ago, with the most recent eruption cycle ending about 1,000 years ago. Over the past half million years, Mount Rainier has erupted again and again, alternating between quiet lava-producing eruptions ...
Mount Rainier, the highest (14,410 feet / 4392 m) volcano in the Cascade Range, towers over a population of more than 3.3 million in the Seattle Tacoma metropolitan area, and its drainage system via the Columbia River potentially impacts another 500,000 residents of southwestern Washington and northwestern Oregon.
A subduction zone is an area where one continental plate is being forced underneath another into the earth's mantel. Mount Rainier experiences about 20 small earthquakes a year, making it the second most seismically active volcano in the northern Cascade Range after Mount St. Helens.
At one time, lava flows on opposite sides of the mountain probably projected more than 1,000 feet (305 meters) above the present summit at Columbia Crest which rises 14,410 feet (4392 meters) above sea level on the rim of the recent lava cone.
Mount Rainier is considered an active volcano and will have future eruptions. Mount Rainier National Park aids with logistical support as the USGS Cascades Volcano Observatory (CVO) conducts monitoring of seismic activity (with the Pacific Northwest Seismic Network), ground deformation, hydrothermal activity, and more to track Mount Rainier’s volcanic activity.
When Mount Rainier erupts again, volcanic activity may affect people living in the surrounding areas, those visiting Mount Rainier National Park, and potentially those flying overhead. Additionally, it will impact a scenic and natural resource that provides recreation, wildlife habitat, and water for drinking and power generation.
Mount Rainier is behaving about as it has over the last half-million years, so all evidence suggests that the volcano will continue to erupt, grow, and collapse.
Weak, hydrothermally altered rocks remain at high elevation on the volcano's west flank, and some of this material could be dislodged by earthquakes during an eruptive period. We cannot rule out the possibility that altered material could collapse due to its own weakness, without a triggering eruption or earthquake.
The coast of the Olympic Peninsula is particularly famous for some of this distinct geology, the history the rock preserves, and the incredible views they create today .
The Olympic Mountains were born in the sea. The basalts and sedimentary rocks that form the mass of these peaks were laid down 18 to 57 million years ago offshore, then uplifted, bent, folded and eroded into the rugged peaks you see today. Off the coast of the Olympic Peninsula, a dramatic story of epic proportions is slowly, yet steadily, ...
These towers of rock that make the peninsula coastline so famous define the views from beaches such as Ruby Beach, Ozette Beach, Shi Shi Beach, Rialto, La Push, and First, Second and Third Beach. Not only shrouded in salty water, but in history and mystery as well, the geology behind these majestic rock outcroppings lies just as much in what we see today as it does in what is no longer there.#N#The jagged sea stacks are a part of the Hoh Rock Assemblage. Long ago, this “Rock Assemblage” would have resembled a sort of geologic chocolate chip cookie dough. Throughout several millennia, there have been a great variety of rock types in the area. The dense volcanic and marine sedimentary rocks would be the chocolate chips amidst the cookie batter of the softer mudstone. At that time, the high cliffs now seen above the beach were sitting at sea level. The driving power of the ocean waves pummeled and weakened the mudstone, washing it away, but the sturdy volcanic chocolate chips remained. The cliffs rose with the same tectonic forces that rose the mountains of the peninsula, and alongside them rose the same volcanic outcroppings that were left behind.
Subduction is just the beginning of the monumental geologic story that is the Washington Peninsula. The mountains of today can be enjoyed from many viewpoints, but are changing each day. Over the course of millions of years, the immense weight of settling sand, mud, and debris on the ocean floor hardened into sedimentary rock. As the two tectonic plates of the area crash together, the Juan de Fuca Plate which holds the ocean and the Olympic Peninsula, is forced downward underneath the land-bearing North American Plate. However, not all of the crust on the oceanic plate makes its way further underground. Much of the built-up sedimentary rock on top of the tectonic plate continues to crumple against the landmass of North America and fold upwards out of the water, rising from the depths as time goes on.
Glaciers will have a blue hue to them because longer wavelengths of light, like the reds, are absorbed quickly into ice and snow, whereas shorter wavelengths, however, like the blues, are spread throughout . Crevasses, or large cracks and gaps, can be seen in glaciers. These are evidence of glaciers shifting and moving.
Moraines are piles of sediment that build up after being deposited or moved from the melting of a glacier. Typically, they are on the boundaries of a glacier, like at the edge (a lateral moraine) or at the end (a terminal moraine). Lakes and ponds can be created by glacial melt.
Lakes and Rivers. Water has directed and been directed in turn by the geologic processes of Olympic National Park that are highlighted below. Each water feature is bound in shape and flow by its geologic past.