What is peridotite composed of

These minerals are more stable when they come into contact with the Earth's surface. Other peridotite rocks when altered form chlorite, serpentinite and talc. This phenomenon is produced by combining carbon dioxide with olivine rich in magnesium, which forms magnesite.

This reaction usually occurs very quickly from a geological point of view. Peridotite rocks contain several types of intrusive igneous rocks. This family of rocks includes: harzburgite, wehrlite, lherzolite, dunite, and kimberlite. Most of these are green in color due to their olivine content. It is basically composed of olivine and orthopyroxene, mixed with small amounts of garnet and spinel. This peridotite is mainly composed of orthopyroxene and clinopyroxene, as well as olivine and hornblende.

It is mainly composed of olivine mixed with significant amounts of clinopyroxene and orthopyroxene. A large part of the Earth's mantle is believed to be made up of lherzolite. This peridotite is composed primarily of olivine, but can contain large amounts of pyroxene, chromite, and spinel. Kimberlite sometimes contains diamonds. To locate them, geologists sometimes use an aerial magnetic survey with equipment that measures their intensity.

Researchers believe that the mantle is composed primarily of these types of rocks. Their study allows us to establish the data of fossils, the ages of the Earth, or even climate change through the sequestration of carbon dioxide.

They allow a better understanding of the constitution of the Earth's mantle. These studies are carried out through ophiolites, large slabs of oceanic crust that emerge to the surface bringing large masses of peridotite. A peridotite is a dense, coarse-grained igneous rock. It depends. A sample from the crust could be a wide variety of colors. A sample of rock from the lithospheric mantle would be green, as it is composed mostly of peridotite.

Log in. Plate Tectonics. See Answer. Best Answer. Study guides. Q: What is Composed of peridotite? Write your answer Related questions. What layer is Composed of peridotite? What is the mineral composition of peridotite? Peridotite is composed almost entirely of dark silicate minerals.? Is basalt in the mantle? Which igneous rock out of granite basalt andesite and peridotite has the lowest silica SiO2 content?

Is peridotite composed primarily of olivine and pyroxene? Is peridotite felsic or mafic? Which types of igneous rocks are composed of at least 50 percent olivine? Peridotite is composed almost entirely of dark sillicate mineralsits chemical composition is referred to as?

What is the composition of earths mantle? Much of the upper mantle thought to be made of granite true or false? Where does a peridotite rock come from?

What type of rock is peridotite? Is peridotite extrusive or intrusive? Photo by Woudloper, used here under a Creative Commons License. Earth's mantle is thought to be composed mainly of peridotite. Some of the occurrences of peridotite on Earth's surface are thought to be rocks from the mantle that have been brought up from depth by deep-source magmas.

Ophiolites and pipes are two structures that have brought mantle peridotite to the surface. Peridotite is also found in the igneous rocks of sills and dikes.

Ophiolites : An ophiolite is a large slab of oceanic crust, including part of the mantle, that has been overthrust onto continental crust at a convergent plate boundary.

These structures bring large masses of peridotite up to Earth's surface and offer a rare opportunity to examine rocks from the mantle. Studies of ophiolites have helped geologists better understand the mantle, the process of seafloor spreading, and the formation of oceanic lithosphere.

Pipes : A pipe is a vertical intrusive structure that forms when a deep-source volcanic eruption brings magma up from the mantle. The magma often breaks through the surface, producing an explosive eruption and a steep-walled crater known as a maar.

These deep-source eruptions are the origin for most of the Earth's primary diamond deposits. The magma that forms the pipe is thought to ascend rapidly from the mantle, tearing rocks free from the mantle and from the walls of the pipe.

These pieces of foreign rock are known as "xenoliths. Xenoliths provide the only way that diamonds can ascend from the mantle to the surface without being melted or corroded by the hot magma.

Dikes and Sills : Dikes and sills are intrusive igneous rock bodies. Some of them are composed of peridotite that was sourced from deep within the Earth. When they are exposed by erosion, they provide another way that peridotite from great depth can be observed at Earth's surface. Certain types of garnet , along with chromite and ilmenite , can be indicator minerals for diamond prospecting.

Public domain image by Woudloper. The formation of diamonds requires very high temperatures and pressures that only occur on Earth at depths of miles below the surface and at locations in the mantle where temperatures are at least degrees Fahrenheit. The diamonds are delivered to the surface in pieces of rock, known as xenoliths, which are torn from the mantle by deep-source volcanic eruptions.

When the mantle material approaches the surface, an explosive eruption occurs that forms a pipe-shaped structure that might be several hundred yards to over a mile in diameter. These "pipes," the rocks that are blasted from them, and the sediments and soils produced by their weathering are the source for most of Earth's natural diamonds. The best way to learn about rocks is to have specimens available for testing and examination. Some peridotites contain significant amounts of chromite.

Some of these form when a subsurface magma slowly crystallizes. During the early stages of crystallization, the highest-temperature minerals such as olivine, orthopyroxene, clinopyroxene, and chromite begin to crystallize from the melt. The crystals are heavier than the melt and sink to the bottom of the melt. These high-temperature minerals can form layers of peridotite on the bottom of the magma body.

These are known as "stratiform deposits. Another type of chromite deposit occurs where tectonic forces push large masses of oceanic lithosphere up onto a continental plate in a structure that is known as an "ophiolite. Aeromagnetic prospecting: Finding small bodies of peridotite such as a kimberlite pipe can be very difficult because they are so small.

Aeromagnetic surveys are sometimes employed to find them. The geographic areas underlain by peridotite will often be a magnetic anomaly in contrast to their surrounding rocks.