The thickest of Earth’s interior layers is the
a. Crust
b. Mantle
c. Outer core
d. Inner core
The Correct Answer and Explanation is :
The correct answer is b. Mantle.
Explanation:
The Earth’s interior is divided into four main layers: the crust, mantle, outer core, and inner core. These layers differ in composition, state, and thickness.
- Crust: The outermost layer of the Earth, the crust is relatively thin compared to the other layers. It is made up of solid rock and is divided into two types: the continental crust (which forms landmasses) and the oceanic crust (which forms the ocean floor). Its thickness ranges from 5-70 kilometers (3-44 miles).
- Mantle: The mantle is the thickest layer of the Earth, extending to a depth of about 2,900 kilometers (1,800 miles). It is composed of silicate rocks rich in iron and magnesium and behaves as a solid, though it is capable of flow over time due to its high temperature and pressure. The mantle is divided into two sections: the upper mantle (which includes the lithosphere and asthenosphere) and the lower mantle, which is more rigid but still flows very slowly. The mantle makes up about 84% of Earth’s volume, and it is much thicker than the crust.
- Outer Core: The outer core is a liquid layer composed primarily of iron and nickel. It lies beneath the mantle and is about 2,200 kilometers (1,367 miles) thick. The movement of the molten iron in the outer core generates Earth’s magnetic field.
- Inner Core: The inner core is the Earth’s innermost layer. It is a solid sphere mainly composed of iron and nickel. It extends from about 5,150 kilometers (3,200 miles) to the Earth’s center, at about 6,371 kilometers (3,959 miles) deep. While the inner core is solid, it is under immense pressure, preventing it from melting.
Thus, the mantle is the thickest layer, forming the largest part of Earth’s interior.
Let me now generate an image showing the layers of the Earth.
Here is the illustration showing the Earth’s interior layers, with the crust, mantle, outer core, and inner core clearly labeled. As you can see, the mantle is the thickest layer, extending far beneath the crust and surrounding the outer core.
