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26-832: The Gonâve microplate forms part of the boundary between the North American plate and the Caribbean plate . It is bounded to the west by the Mid-Cayman Rise spreading center , to the north by the Septentrional-Oriente fault zone and to the south by the Walton fault zone and the Enriquillo–Plantain Garden fault zone . The existence of this microplate was first proposed in 1991. This has been confirmed by GPS measurements, which show that

52-618: A mantle convective current is propelling the plate. Eurasian plate The Eurasian plate is a tectonic plate that includes most of Eurasia (a landmass consisting of the traditional continents of Asia and Europe ), with the notable exceptions of the Arabian Peninsula , the Indian subcontinent , and the area east of the Chersky Range in eastern Siberia . It also includes oceanic crust extending westward to

78-404: The Chersky Range in eastern Siberia. The plate includes both continental and oceanic crust . The interior of the main continental landmass includes an extensive granitic core called a craton . Along most of the edges of this craton are fragments of crustal material called terranes , which are accreted to the craton by tectonic actions over a long span of time. Much of North America west of

104-801: The Fifteen-Twenty fracture zone around 16°N. On the northerly boundary is a continuation of the Mid-Atlantic Ridge called the Gakkel Ridge . The rest of the boundary in the far northwestern part of the plate extends into Siberia . This boundary continues from the end of the Gakkel Ridge as the Laptev Sea Rift , on to a transitional deformation zone in the Chersky Range , then the Ulakhan Fault between it and

130-710: The Gonâve microplate , and the parallel Puerto Rico Trench running north of Puerto Rico and the Virgin Islands and bounding the Puerto Rico–Virgin Islands microplate , are also a part of the boundary. The rest of the southerly margin which extends east to the Mid-Atlantic Ridge and marks the boundary between the North American plate and the South American plate is vague but located near

156-613: The Mid-Atlantic Ridge and northward to the Gakkel Ridge . The western edge is a triple junction plate boundary with the North American plate and Nubian plate at the seismically active Azores triple junction extending northward along the Mid-Atlantic Ridge towards Iceland . Ridges like the Mid-Atlantic ridge form at a divergent plate boundary . They are located deep underwater and very difficult to study. Scientists know less about ocean ridges than they do

182-788: The Miocene period and are still geologically active, creating earthquakes and volcanoes. The Yellowstone hotspot is most notable for the Yellowstone Caldera and the many calderas that lie in the Snake River Plain , while the Anahim hotspot is most notable for the Anahim Volcanic Belt in the Nazko Cone area. For the most part, the North American plate moves in roughly a southwest direction away from

208-991: The Okhotsk microplate , and finally the Aleutian Trench to the end of the Queen Charlotte Fault system (see also: Aleutian Arc ). The westerly boundary is the Queen Charlotte Fault running offshore along the coast of Alaska and the Cascadia subduction zone to the north, the San Andreas Fault through California , the East Pacific Rise in the Gulf of California , and the Middle America Trench to

234-778: The Rocky Mountains is composed of such terranes. The southern boundary with the Cocos plate to the west and the Caribbean plate to the east is a transform fault , represented by the Swan Islands Transform Fault under the Caribbean Sea and the Motagua Fault through Guatemala . The parallel Septentrional and Enriquillo–Plantain Garden faults running through Hispaniola and bounding

260-524: The 1783 eruption of Laki and the 2010 eruption of Eyjafjallajökull , are caused by the North American and the Eurasian plates moving apart, which is a result of divergent plate boundary forces. The convergent boundary between the Eurasian plate and the Indian plate formed the Himalayas mountain range. The geodynamics of Central Asia is dominated by the interaction between the Eurasian plate and

286-709: The Farallon plate. The boundary along the Gulf of California is complex. The gulf is underlain by the Gulf of California Rift Zone , a series of rift basins and transform fault segments from the northern end of the East Pacific Rise in the mouth of the gulf to the San Andreas Fault system in the vicinity of the Salton Trough rift/ Brawley seismic zone . It is generally accepted that a piece of

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312-643: The Gonâve microplate. It has been suggested that the Gonave microplate will also become accreted to the North American plate, as all the plate boundary displacement transfers onto the southern fault system. North American plate It extends eastward to the seismically active Mid-Atlantic Ridge at the Azores triple junction plate boundary where it meets the Eurasian plate and Nubian plate . and westward to

338-599: The Mid-Atlantic Ridge at a rate of about 2.3 centimeters (~1 inch) per year. At the same time, the Pacific plate is moving to the northwest at a speed of between 7 and 11 centimeters (~3-4 inches) per year. The motion of the plate cannot be driven by subduction as no part of the North American plate is being subducted, except for a small section comprising part of the Puerto Rico Trench ; thus other mechanisms continue to be investigated. One study in 2007 suggests that

364-448: The North American plate was broken off and transported north as the East Pacific Rise propagated northward, creating the Gulf of California. However, it is as yet unclear whether the oceanic crust between the rise and the mainland coast of Mexico is actually a new plate beginning to converge with the North American plate, consistent with the standard model of rift zone spreading centers generally. A few hotspots are thought to exist below

390-580: The North American plate. The most notable hotspots are the Yellowstone (Wyoming), Jemez Lineament (New Mexico), and Anahim (British Columbia) hotspots. These are thought to be caused by a narrow stream of hot mantle convecting up from the Earth's core–mantle boundary called a mantle plume , although some geologists think that upper mantle convection is a more likely cause. The Yellowstone and Anahim hotspots are thought to have first arrived during

416-701: The boundary from the Nansen Ridge through a broad zone of deformation in North Asia to the Sea of Okhotsk then south through Sakhalin Island and Hokkaido to the triple junction in the Japan Trench . But this simple view has been successfully challenged by more recent research. During the 1970s, Japan was thought to be located on the Eurasian plate at a quadruple junction with the North American plate when

442-532: The eastern boundary of the North American plate was drawn through southern Hokkaido . New research in the 1990s supported that the Okhotsk microplate was independent from the North American plate and a boundary with the Amurian microplate , sometimes described as "a division within the Eurasian plate" with an unknown western boundary. All volcanic eruptions in Iceland, such as the 1973 eruption of Eldfell ,

468-708: The future microplate was still firmly attached to the Caribbean plate. During the Late Miocene , the part of the Caribbean plate formed by Hispaniola began to collide with the Bahamas platform and a new strike-slip fault system developed through Jamaica and southern Hispaniola, the Enriquillo–Plantain Garden fault zone, isolating part of the Cayman Trough and the central part of Hispaniola to form

494-415: The northern and southern boundaries approach the eastern edge of the Caribbean plate they become less distinct and the eastern boundary is not as well defined. The presence of a separate Gonâve microplate was first suggested by the analysis of sidescan sonar results from the Cayman Trough. This study found evidence for continuous transform type faults along the southern flank of the trough, to both sides of

520-420: The overall displacement between the two main plates is split almost equally between the transform fault zones that bound the Gonâve microplate. The microplate is expected to eventually become accreted to the North American plate. The Gonâve microplate is an approximately 1,100 km long strip, consisting mainly of oceanic crust of the Cayman Trough but including island arc material at its eastern end on

546-814: The planets of the solar system. There is another triple junction where the Eurasian plate meets the Anatolian sub-plate and the Arabian plate . The Anatolian sub-plate is currently being squeezed by the collision of the Eurasian plate with the Arabian plate in the East Anatolian Fault Zone . The boundary between the North American plate and the Eurasian plate in the area around Japan has been described as "shifty". There are different maps for it based on recent tectonics, seismicity and earthquake focal mechanism . The simplest plate geometry draws

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572-517: The south, effectively cutting off this northern area and accreting it to the North American plate. A large left-stepping offset formed along this zone just east of the Yucatán peninsula creating a pull-apart basin , which continued to extend until the onset of seafloor spreading, creating the Cayman spreading centre. Further movement on this fault system created the Cayman Trough, although at that time

598-554: The south. On its western edge, the Farallon plate has been subducting under the North American plate since the Jurassic period. The Farallon plate has almost completely subducted beneath the western portion of the North American plate, leaving that part of the North American plate in contact with the Pacific plate as the San Andreas Fault. The Juan de Fuca , Explorer , Gorda , Rivera , Cocos and Nazca plates are remnants of

624-534: The southern one. This observation is consistent with the eventual accretion of the Gonâve microplate to the North American plate. The Gonâve microplate began to form in the Early Eocene after the northern part of the leading edge of the Caribbean plate (present day Cuba ) collided with the Bahamas platform . This part of the plate was unable to move further to the east and a transform fault system developed to

650-417: The spreading centre. GPS data supports the existence of the microplate by showing that the relative motion between the North American and Caribbean plates is split almost equally between the two bounding transform fault systems. Comparison of these rates with observations of magnetic stripes within the Cayman Trough suggests that displacement is increasingly being transferred from the northern fault system to

676-607: The western part of Hispaniola . Further east a separate Hispaniola Microplate has been identified. At its western end, the Gonâve microplate is bounded by the mid-Cayman spreading centre. To the north it is bounded by the Septentrional-Oriente fault zone and to the south by a more complex strike-slip fault system that includes the Walton fault and the Enriquillo-Plantain Garden fault zone. As

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