Table of Contents
What is the sinking of regions of the crust to lower elevations?
subsidence
subsidence: the sinking of regions of the Earth’s crust to lower elevations.
What is it called when parts of Earth’s crust sink?
A subduction zone is the biggest crash scene on Earth. These boundaries mark the collision between two of the planet’s tectonic plates. At a subduction zone, the oceanic crust usually sinks into the mantle beneath lighter continental crust.
What is lower crust part of the crust known as?
The sima layer is also called the basal crust or basal layer because it is the lowest layer of the crust. Because the ocean floors are mainly sima, it is also sometimes called the oceanic crust.
Which is the lower layer of the earth crust?
mantle
Earth has three layers: the crust, the mantle, and the core. The crust is made of solid rocks and minerals. Beneath the crust is the mantle, which is also mostly solid rocks and minerals, but punctuated by malleable areas of semi-solid magma.
What is the strong lower part of the mantle?
Chapter 7 vocabulary
| A | B |
|---|---|
| mesosphere | literally, the “middle sphere”- the strong, lower part of the mantle between the asthenosphere and the outer core |
| outer core | the liquid layer of the Earth’s core that lies beneath the mantle and surrounds the inner core |
| inner core | the solid, dense center of the earth |
What word characterizes the lower mantle?
The lower mantle, historically also known as the mesosphere, represents approximately 56% of Earth’s total volume, and is the region from 660 to 2900 km below Earth’s surface; between the transition zone and the outer core.
Where is the lower crust?
The lower oceanic crust is the lower part of the oceanic crust and represents the major part of it (volumetrically biggest part). It is generally located 4–8 km below the ocean floor and the major lithologies are mafic (ultramafic and gabbroic rocks) which derive from melts rising from the earth’s mantle.
What is the lower density type of crust?
Continental crust
Continental crust is also less dense than oceanic crust, whose density is about 2.9 g/cm3. At 25 to 70 km, continental crust is considerably thicker than oceanic crust, which has an average thickness of around 7–10 km. About 40% of Earth’s surface area and about 70% of the volume of Earth’s crust is continental crust.
What does the crust float on?
Because both continental and oceanic crust are less dense than the mantle below, both types of crust “float” on the mantle.
What does Lithos mean in geography?
“Litho” is from the Greek word lithos, meaning stone. “Sphere” is from the Greek word sphaira, meaning globe or ball. The solid outer crust of any celestial body can also be called the lithosphere.
How is the Earth’s crust sinking to lower elevations?
The sinking of regions of the Earth’s crust to lower elevations. The hypothesis that states that the continents onced formed a single landmass, broke up, and drifted tho their present location. The process by which new oceanic lithosphere forms as magma rises toward the surface and solidifies. What is the definition of Sea-floor Spreading?
What makes up the solid layer of the Earth?
The solid, outer layer of the Earth that consists of the crust and the rigid upper part of the mantle. The soft layer of the mantle on which the tectonic plates move. What is the definiton of Asthenosphere? The rising of regions of the Earth’s crust to higher elevations.
What is the process by which new oceanic lithosphere forms?
The process by which new oceanic lithosphere forms as magma rises toward the surface and solidifies. Stress that occurs when forces act to stretch an object. What is the definition of Plate Tectonics?
What is the central part of the earth below the mantle?
The central part of the Earth below the mantle. The thin and solid outermost layer of the Earth above the mantle. The strong lower part of the mantle between the asthenosphere and the outer core. What is the definiton of Mantle? What is the definiton of Core? The central part of the Earth below the mantle.