granite
Granitic rock is a material that is primarily found in continental crust. It is composed of minerals like quartz, feldspar, and mica, and is associated with the lighter composition characteristic of continental crust compared to oceanic crust.
Short Answer: The Earth has two types of crust, continental crust and oceanic crust. Basaltic rocks are the main component of oceanic crust. Continental crust consists mainly of lower density granitic rocks. The Better Answer: Tectonic plates and the Earth's crust are not the same thing. Tectonic plates are made of the Earth's crust, plus the upper layers of the Earth's mantle. Together the crust and the more solid upper mantle form the lithosphere. The crust itself is relatively thin, varying from a few kilometers thick to nearly a hundred kilometers. With the material of the mantle, the tectonic plates are 50 to 200 kilometers thick. Some plates are entirely continental and some are entirely oceanic and some are combined. Continental crust and oceanic crust are different in make up and properties. The continental crust has a density of about 2.7 g/cm3 and is mostly granitic, made of silicate materials with more aluminum and less iron and magnesium. Continental crust is generally thicker, in the range of 25 to 70 kilometers. Oceanic crust is more dense (density of about 2.9 g/cm3) and the average oceanic thickness is in the range of 7-10 kilometers. Oceanic crust is primarily basalt, composed of silicate material which is rich in iron and magnesium. Though only 40% of the Earth's surface is continental crust, there is more of it because it is thicker. Continental crust is about 70% of the volume of Earth's crust. Both types of crusts are less dense than the material of the Earth's mantle (density of about 3.3 g/cm3), so the "float" on the mantle.
No. Oceanic crust is heavier and denser than continental crust, but is actually thinner. Continental crust is believed to actually extend down into the magma of the mantle (upon which crust floats) more deeply than oceanic crust, similar to how a huge ice cube will not only be larger above the surface of water than a smaller ice cube, but will extend more deeply into a glass than a small ice cube ... so not only does continental crust extend higher on the surface (since it is continental crust, it has dry land above the ocean floor), but the 'bottom' of the crust also extends deeper into the earth. Oceanic crust is thus thinner than continental crust, but made of denser, heavier rock (which is why it subducts under continental crusts where continental and oceanic plates converge).
No, earthquakes can occur anywhere in the crust, oceanic crust or continental crust. An earthquake occurs when the hard brittle solid material of the crust fractures under stress. Earthquakes cannot occur deeper than the crust (the mantle is plastic and flows slowly under stress instead of fracturing, the outer core is liquid and flows even easier than the mantle).
Two differences are that the oceanic crust is more dense than continental, and continental crust is composed mostly of granite, while oceanic is mostly basalt
Granitic rock is a material that is primarily found in continental crust. It is composed of minerals like quartz, feldspar, and mica, and is associated with the lighter composition characteristic of continental crust compared to oceanic crust.
The oldest continental crust is significantly older than the oldest oceanic crust. The oldest continental rocks, found in regions like Canada and Australia, are over 4 billion years old. In contrast, the oldest oceanic crust, located at the bottom of the Atlantic Ocean, is only about 200 million years old, as it is continuously created and destroyed through the process of plate tectonics. This stark difference highlights the stability and longevity of continental crust compared to the dynamic nature of oceanic crust.
Short Answer: The Earth has two types of crust, continental crust and oceanic crust. Basaltic rocks are the main component of oceanic crust. Continental crust consists mainly of lower density granitic rocks. The Better Answer: Tectonic plates and the Earth's crust are not the same thing. Tectonic plates are made of the Earth's crust, plus the upper layers of the Earth's mantle. Together the crust and the more solid upper mantle form the lithosphere. The crust itself is relatively thin, varying from a few kilometers thick to nearly a hundred kilometers. With the material of the mantle, the tectonic plates are 50 to 200 kilometers thick. Some plates are entirely continental and some are entirely oceanic and some are combined. Continental crust and oceanic crust are different in make up and properties. The continental crust has a density of about 2.7 g/cm3 and is mostly granitic, made of silicate materials with more aluminum and less iron and magnesium. Continental crust is generally thicker, in the range of 25 to 70 kilometers. Oceanic crust is more dense (density of about 2.9 g/cm3) and the average oceanic thickness is in the range of 7-10 kilometers. Oceanic crust is primarily basalt, composed of silicate material which is rich in iron and magnesium. Though only 40% of the Earth's surface is continental crust, there is more of it because it is thicker. Continental crust is about 70% of the volume of Earth's crust. Both types of crusts are less dense than the material of the Earth's mantle (density of about 3.3 g/cm3), so the "float" on the mantle.
Some geologists believe there are no tectonic plates composed solely of continental crust, as plates typically consist of both continental and oceanic crust. The concept of a plate composed entirely of continental crust is not widely accepted in the field of plate tectonics.
No. Oceanic crust is heavier and denser than continental crust, but is actually thinner. Continental crust is believed to actually extend down into the magma of the mantle (upon which crust floats) more deeply than oceanic crust, similar to how a huge ice cube will not only be larger above the surface of water than a smaller ice cube, but will extend more deeply into a glass than a small ice cube ... so not only does continental crust extend higher on the surface (since it is continental crust, it has dry land above the ocean floor), but the 'bottom' of the crust also extends deeper into the earth. Oceanic crust is thus thinner than continental crust, but made of denser, heavier rock (which is why it subducts under continental crusts where continental and oceanic plates converge).
No, earthquakes can occur anywhere in the crust, oceanic crust or continental crust. An earthquake occurs when the hard brittle solid material of the crust fractures under stress. Earthquakes cannot occur deeper than the crust (the mantle is plastic and flows slowly under stress instead of fracturing, the outer core is liquid and flows even easier than the mantle).
Two differences are that the oceanic crust is more dense than continental, and continental crust is composed mostly of granite, while oceanic is mostly basalt
The continental crust is about 35 to 40 kilometers thick, while the oceanic crust averages at about 7-10 kilometers thick. This means that the continental crust is about 3.5 to 4 times the thickness of the oceanic crust.
Oceanic crust is 6 to 11 kilometers thick while the continental crust is 100 kilometers thick, so the continental crust is more than five times as thick as the oceanic crust. I hope this well will help for the future and current time.
yes but oceanic crust is younger than continental crust because of deep sea trenches
No. It only occurs in areas of continental crust and is only present at the surface in a small percentage of that.
Continental crust is typically about 30-50 km thick, whereas oceanic crust is only about 5-10 km thick. This difference in thickness is primarily due to variations in composition and density between the two types of crust. Continental crust is made up of less dense, older rocks, while oceanic crust is composed of denser, younger basaltic rocks.