It is subducting under (that is, being forced under) the South American plate. Before we talk about processes at plate boundaries, its important to point out that there are never gaps between plates. This plate is moving directly east towards the South America plate. This is the zone where the two plates have been locked together since the last great earthquake occurred in the year 1700. The park is a complex amalgamation of blocks of continental and oceanic crust that have slammed into North America. Massive areas of granite from the cooled magma chambers that fed the volcanoes form portions of the Sierra Nevada Mountains, including Yosemite National Park. Hood in Oregon, Mt. Modified from The Geology of our National Parks, Monuments and Seashores, by Robert J. Lillie, New York, W. W. Norton and Company, 298 pp., 2005, www.amazon.com/dp/0134905172. The San Andreas Fault and Queen Charlotte Fault are transform plate boundaries developing where the Pacific Plate moves northward past the North American Plate. It was preceded by Pannotia (600 to 540 Ma), by Rodinia (1,100 to 750 Ma), and by others before that. The best example is the San Andreas Fault on the Pacific coast of the United States. Sediment that has accumulated on the continental slope is thrust up into an accretionary wedge, and compression leads to thrusting within the continental plate (Figure \(\PageIndex{7}\)). Shasta in California, and other Cascade Volcanoes. Unclick all the other layers you've been using, and then click next to . The devastating 1985 Mexico City earthquake and the 2017 Chiapas earthquake were results of the subduction of the Cocos Plate beneath the North American Plate. The Pacific plate is subducting beneath the Philippine Sea plate to the east while the west/northwestern part of the Philippine Sea plate is subducting beneath the continental Eurasian plate. Roughly 3.2 million square kilometres (1.2 million square miles) in area, the Caribbean Plate borders the North American Plate, the South American Plate, the Nazca Plate and the Cocos Plate. The Coast Range (accretionary wedge), Great Valley (forearc basin), and Sierra Nevada (volcanic arc) still reflect the subduction zone topography. The eruption of Mt. As explained above, most transform faults connect segments of mid-ocean ridges and are thus ocean-ocean plate boundaries (Figure \(\PageIndex{11}\)). The southerly side is a divergent boundary with the Antarctic Plate called the Southeast Indian Ridge (SEIR). Drum (right). But unlike Mt. What type of plate boundary is between the Nazca and Cocos Plate? In central and southern California the ancient volcanoes have largely eroded away. The map shows the major tectonic plates that compose Earth's crust and upper mantle Arrows indicate direction of plate movement and the size of the arrows indicate rate of movement. The subduction of the Nazca plate under southern Chile has a history of producing massive earthquakes, including the largest ever recorded on earth, the moment magnitude 9.5 1960 Valdivia earthquake. Mazama, Aniakchak no longer holds a large lake because the caldera wall is breached. To see the timing of these processes for yourself, go to time lapse of Continental Movements. This beauty is part of the reason that residents and visitors have learned to tolerate, and develop ways to mitigate, the effects of earthquakes, tsunamis and volcanic eruptionsbeasts that are consequences of the same tectonic forces that create the regions beauty. Modified from Earth: Portrait of a Planet", by S. Marshak, 2001, W. W. Norton & Comp., New York. Examples of ocean-ocean convergent zones are subduction of the Pacific Plate beneath the North America Plate south of Alaska (Aleutian Islands) and beneath the Philippine Plate west of the Philippines, subduction of the India Plate beneath the Eurasian Plate south of Indonesia, and subduction of the Atlantic Plate beneath the Caribbean Plate (see Figure \(\PageIndex{1}\)). Five park sites in southern Alaska showcase landscapes formed by the subduction of the northward-moving Pacific Plate beneath North America. The eruption of Aniakchak Volcano about 3,500 years ago rivals the eruption and collapse of Mt. This plate is moving north east towards the Eurasia plate and the Pacific plate. Beginning about 30 million years ago, so much of the Farallon Plate was consumed by subduction that the Pacific and North American plates were in contact, forming the San Andreas transform plate boundary in western California. Subduction in the Pacific Northwest creates incredible beauty in the form of coastlines, mountains, and valleysiconic features of the many National Park Service sites in the region. As discussed in the context of subduction-related volcanism in Chapter 4, the significant volume of water within the subducting material is released as the subducting crust is heated. More than 40 volcanoes have erupted in Alaska since Russians first arrived in the mid 1700s a great many of the volcanoes are in areas that are now National Park Service sites. Silica-rich ash melted and coated the hot engine turbines with glass, causing all four of them to shut down. The part of the plate around the Australia plate is moving southwards. A sudden unlocking could produce an earthquake every bit as big as the one that occurred in Alaska in 1964, when a similar subduction zone boundary snap occurred. Regional tectonics of Central America are mainly controlled by the collision of the Cocos and the Caribbean plates. The Sierra Nevada are a remnant of volcanoes that extended southward when the ancient Farallon Plate dove beneath the edge of North America. Today This plate is moving north east towards the Arabia and Eurasia plates. WrangellSt. Note that the dark blue line does not run further up the coast. Yosemite Valley and Half Dome. A by-product of the metamorphism is the release of hot fluids, especially water. The Nazca plate is an oceanic tectonic plate in the southeastern Pacific Ocean that shares both convergent and divergent boundaries, corners multiple triple junctions, contains three seamount chains, overrides four hotspots, and is responsible for the creation of the Andean orogeny (Figure 1). Find the boundary between the North American and Cocos plates. The rocks on top of the plate are metamorphosed due to the great temperatures and pressures at those depths. Modified from Oregon's Island in the Sky: Geology Road Guide to Marys Peak, by Robert J. Lillie, Wells Creek Publishers, 75 pp., 2017, www.amazon.com/dp/1540611965. Gases may be trapped in them under high pressure. What is the example of transform boundary? For example, the Queen Charlotte Fault connects the north end of the Juan de Fuca Ridge, starting at the north end of Vancouver Island, to the Aleutian subduction zone. The subduction formed a line of volcanoes stretching all the way from Alaska to Central America. A convergent plate boundary is a location where two tectonic plates are moving toward each other, often causing one plate to slide below the other (in a process known as subduction). Ancient magma chamber rocks can be exposed if subduction stops and the volcanoes erode away. It is released when the oceanic crust is heats and then rises and mixes with the overlying mantle. National Park Service sites are shown in red. St. Helens. Sandstone and shale layers at Kenai Fjords are commonly metamorphosed and were so deformed during subduction and uplift that they are vertical in places. The largest earthquakes occur near the surface where the subducting plate is still cold and strong. With continued uplift and erosion, most of the volcanic material would erode. The distribution and depths of earthquakes in the Caribbean and Central America area are shown in Figure 11.2.3. Eurasia plate, Pacific plate, Africa plate, Caribbean plate, South America plate, Cocos plate, Juan de Fuca plate. Kenai Fjords National Park lies within a coastal mountain range (accretionary wedge) formed as the Pacific Plate subducts beneath southern Alaska. Volcanic and metamorphic rocks exposed in Kenai Fjords National Park reveal the incredible forces that occur at an ocean/continent subduction zone. Explain why the Nootka Fault is a transform fault, and show the relative sense of motion along the fault with two small arrows. Sites in the Sierra Nevada Mountains reveal the eroded roots of an ancient volcanic range that formed when the subduction zone extended much farther south. KEFJKenai Fjords National Park, Alaska[Geodiversity Atlas] [Park Home], CRLACrater Lake National Park, Oregon[Geodiversity Atlas] [Park Home], LAVOLassen Volcanic National Park, California[Geodiversity Atlas] [Park Home], MORAMount Rainier National Park, Washington[Geodiversity Atlas] [Park Home], ANIAAniakchak National Monument and Preserve, Alaska[Geodiversity Atlas] [Park Home], KATMKatmai National Park, Alaska[Geodiversity Atlas] [Park Home], LACLLake Clark National Park, Alaska[Geodiversity Atlas] [Park Home]. Listing total number of features into an ArcGIS Online feature pop-up, Convergent boundaries: where two plates are colliding. Rainier in Mt. And very large parks in the Southern Alaska Subduction Zone display magnificent mountains, rock layers and active volcanoes that tell the story ongoing plate convergence along the North Pacific Coast. The ocean area along southern Asia up to the India plate is also a part of the Australia plate. The 6-mile (10-kilometer) wide caldera is about 2,000 feet (600 meters) deep. This plate starts at the western edge of South America and stretches east into the southwestern parst of the Atlantic Ocean. More recent studies of continental matchups and the magnetic ages of ocean-floor rocks have enabled us to reconstruct the history of the break-up of Pangea. Download the official NPS app before your next visit, Accretionary WedgeCoast Ranges [3 parks], Accretionary WedgeSouthern Alaska [1park]. The Nazca plate is a large tectonic plate that underlies the Pacific Ocean near the western coast of South America. The rising hot water causes overlying rock to melt, generating magma that at times erupts out on the surface as lava flows and other materials forming Mt. Photo courtesy of Robert J. Lillie. The vent was the source for most of the ash and pyroclastic flows expelled during the 1912 eruptions, and has since filled with a lava dome known as Novarupta. The Cocos Plate Examine the interactive globe. The Philippine Sea Plate. Mount Rainier. Australia plate, Eurasia plate, Africa plate, Arabia plate. Crater Lake. Volcanoes in national parks in the Cascades have eruptive personalities that reflect the complex magma systems associated with subduction zones. Igneous, sedimentary, and metamorphic rocks are all found in abundance. Mazama, Aniakchak spewed lava across its caldera floor for centuries after its collapse. A glance at a map of the western United States might suggest that the Sierra Nevada are a southward continuation of the Cascade Volcanoes. Three others, Aniakchak National Monument, Katmai National Park, and Lake Clark National Park, are farther inland, along the active volcanic arc. The western boundary is another mid-ocean ridge, the East Pacific Rise. Taiwan area is the collision boundary between the Philippine Sea plate and the Eurasia plate, which has complex interaction, attracting much attention[3033]. In this region, the Cocos Plate is subducting beneath the North America and Caribbean Plates (ocean-continent convergence), and the South and North America Plates are subducting beneath the Caribbean Plate (ocean-ocean convergence). Photo courtesy of Robert J. Lillie. This plate makes up all of Antarctica and much of the surrounding ocean. Ranger Jens Oreo Demo This can be demonstrated by stacking the three quarters with California on the bottom, overlain by Oregon and then Washington. Is the Nazca plate convergent or divergent? The subducting boundary through Indonesia is not parallel to the biogeographical Wallace line that separates the indigenous fauna of Asia from that of Australasia. Convergent boundaries, where two plates are moving toward each other, are of three types, depending on whether oceanic or continental crust is present on either side of the boundary. Divergent boundaries are spreading boundaries, where new oceanic crust is created to fill in the space as the plates move apart. Mount Rainier is a 14,000 foot (4,300 meter) volcano in the Cascade Range developed above the place where the subducting Juan de Fuca Plate reaches sufficient depth to release hot fluids into the overriding North American Plate. The magma, which is lighter than the surrounding mantle material, rises through the mantle and the overlying oceanic crust to the ocean floor where it creates a chain of volcanic islands known as an island arc. Plates are thought to move along the lithosphere-asthenosphere boundary, as the asthenosphere is the zone of partial melting. Two parallel mountain ranges commonly develop above such a subduction zone a coastal range consisting of sedimentary strata and hard rock lifted out of the sea (accretionary wedge), and a volcanic range farther inland (volcanic arc). Kenai Fjords National Park This plate includes Australia and much of the surrounding ocean. Storms coming in from the Pacific Ocean drop most of their moisture on the Coast Range and Cascades, leaving eastern Oregon and Washington high and dry. Between 200 and 150 Ma, rifting started between South America and Africa and between North America and Europe, and India moved north toward Asia. What type of plate boundary is the Cocos Plate? Adding TravelTime as Impedance in ArcGIS Network Analyst? Crater Lake National Park has the 9th deepest lake in the world. The buoyancy of the mantle plume material creates a dome within the crust, causing it to fracture in a radial pattern, with three arms spaced at approximately 120 (Figure \(\PageIndex{5}\)). Many rift valleys are part of " triple junctions," a type of divergent boundary where three tectonic plates meet at about 120 angles. Rates of motions of the major plates range from less than 1 cm/y to over 10 cm/y. A map of the ocean floor reveals a deep underwater trench (dark blue line) running along the southern coast of Mexico, defining the boundary between two tectonic plates. The North American Plate, for example, rotates counter-clockwise; the Eurasian Plate rotates clockwise. There is strong evidence around the margins of the Atlantic Ocean that this process has taken place before. Photo courtesy of Robert J. Lillie. The southern boundary is a mid-oceanic ridge, the Galapagos Rise. The Philippine Sea plate is tectonically unusual in that almost all the boundaries are convergent. Examples of continent-continent convergent boundaries are the collision of the India Plate with the Eurasian Plate, creating the Himalaya Mountains, and the collision of the African Plate with the Eurasian Plate, creating the series of ranges extending from the Alps in Europe to the Zagros Mountains in Iran. At spreading centres, the lithospheric mantle may be very thin because the upward convective motion of hot mantle material generates temperatures that are too high for the existence of a significant thickness of rigid lithosphere (Figure \(\PageIndex{8}\)). St. Helens in 1980. It is suggested that this type of valley eventually develops into a linear sea (such as the present-day Red Sea), and finally into an ocean (such as the Atlantic). The Cocos Plate is a young oceanic tectonic plate beneath the Pacific Ocean off the west coast of Central America, named for Cocos Island, which rides upon it. See Appendix 3 for Exercise 10.5 answers. Elias National Park We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. Some geological processes act so slowly that we may think of the Earth as rock-solid and unmoving. The grinding action also produces devastating earthquakes, including some that result in giant tsunami waves. To the north it borders the North American Plate, which encompasses the entire north of the continent. The Nazca plate is a large tectonic plate that underlies the Pacific Ocean near the western coast of South America. The most famous example of a transform boundary is the San Andreas Fault in California. This plate includes the northeastern part of the Atlantic ocean, all of Europe, all of Russia (except its most eastern part), and down through southeast Asia, including China and Indonesia. By the end of 1967 the Earths surface had been mapped into a series of plates (Figure \(\PageIndex{1}\)). It separates the Pacific Plate to the west from (north to south) the North American Plate, the Rivera Plate, the Cocos Plate, the Nazca Plate, and the Antarctic Plate. For example the Juan de Fuca Plate is actually three separate plates (Gorda, Juan de Fuca, and Explorer) that all move in the same general direction but at slightly different rates.