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The Iceland Plateau or Icelandic Plateau is an
The Icelandic Plateau began forming approximately 56 Ma, due to the opening of the North Atlantic. As the plates began to diverge from each other, piles of lava rose to the surface, creating the ridges present on the landscape currently.
The plateau is an example of
The Iceland Plateau or Icelandic Plateau is an oceanic plateau
An oceanic or submarine plateau is a large, relatively flat elevation that is higher than the surrounding relief with one or more relatively steep sides.
There are 184 oceanic plateaus in the world, covering an area of or about 5.11% of the ...
in the North Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Africa, Europe an ...
consisting of Iceland
Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its s ...
and its contiguous shelf and marginal slopes. The landscape is constantly experiencing deformation due to the continual addition of magma to the surface and the shifting of the ocean ridge.
Location and Characteristics
The Iceland Plateau is bounded on the south by theReykjanes Ridge
The Mid-Atlantic Ridge is a mid-ocean ridge (a divergent or constructive plate boundary) located along the floor of the Atlantic Ocean, and part of the longest mountain range in the world. In the North Atlantic, the ridge separates the North Ame ...
, on the west by the Greenland-Iceland Ridge, on the north by the Kolbeinsey Ridge
The Kolbeinsey Ridge is a segment of the Mid-Atlantic Ridge located to the north of Iceland in the Arctic Ocean. It is bounded to the south by the Tjörnes Fracture Zone, which connects the submarine ridge to the on-shore Northern Volcanic Zone ri ...
, and on the east by the Iceland-Faeroe Ridge. It consists of a large igneous province
A large igneous province (LIP) is an extremely large accumulation of igneous rocks, including intrusive (sills, dikes) and extrusive (lava flows, tephra deposits), arising when magma travels through the crust towards the surface. The formation ...
that has been volcanically active since at least the Miocene
The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
epoch. The plateau has an average elevation of 1,700 meters above sea level.
The geology of the Icelandic Plateau consists of three layers, closely mimicking the structure of oceanic crust but with one key difference, the second layer of the oceanic crust does not contain piles of lava flow like the Icelandic Plateau does. The first layer is composed of mainly sedimentary rock, the second layer is piles of lava flows, and the third layer is a thick layer of gabbro
Gabbro () is a phaneritic (coarse-grained), mafic intrusive igneous rock formed from the slow cooling of magnesium-rich and iron-rich magma into a holocrystalline mass deep beneath the Earth's surface. Slow-cooling, coarse-grained gabbro is che ...
.
Tectonics and Geology
The Icelandic Plateau began forming approximately 56 Ma, due to the opening of the North Atlantic. As the plates began to diverge from each other, piles of lava rose to the surface, creating the ridges present on the landscape currently.
The plateau is an example of ridge
A ridge or a mountain ridge is a geographical feature consisting of a chain of mountains or hills that form a continuous elevated crest for an extended distance. The sides of the ridge slope away from the narrow top on either side. The line ...
- hotspot interaction. The plateau resides above a hot spot on an active rift
In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics.
Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-grabe ...
zone of the Mid-Atlantic Ridge
The Mid-Atlantic Ridge is a mid-ocean ridge (a divergent or constructive plate boundary) located along the floor of the Atlantic Ocean, and part of the longest mountain range in the world. In the North Atlantic, the ridge separates the North Ame ...
from which extensive tholeiitic
The tholeiitic magma series is one of two main magma series in subalkaline igneous rocks, the other being the calc-alkaline series. A magma series is a chemically distinct range of magma compositions that describes the evolution of a mafic magma i ...
plateau basalts
Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% of a ...
and a number of large rhyolitic
Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture, but may be porphyritic, containing larger mineral crystals (phenocrysts) in an otherwise fine-grained groundmass. The mineral ...
domes
A dome () is an architectural element similar to the hollow upper half of a sphere. There is significant overlap with the term cupola, which may also refer to a dome or a structure on top of a dome. The precise definition of a dome has been a m ...
have been extruded.
As the plates began to diverge from each other, piles of lava rose to the surface from the hot spot, creating the ridges present on the landscape currently.
Today, there are two main parts of the island, one which is slanted towards the sea floor, and another at a level surface.
References