EARTH

Question 1

is a Germanic word, which simply means “the ground.”

only the fifth largest planet in the solar system, it is the only world in our solar system with liquid water on the surface.

the third planet from the Sun, and the only place we know of so far that’s
inhabited by living things

Answer 1

EARTH

Question 2

FACTS

Answer 2

Age: 4.543 billion years
Distance from Sun: 149.6 million km
Gravity: 9.807 m/s2
Radius: 6,371 km
Mass: 5.972 × 10^24 kg
Population: 7.888 billion (2021)

Question 3

LAYERS OF EARTH

Answer 3

the crust, the mantle, the outer
core, and the inner core.

Question 4

• describes the outermost shell of a terrestrial planet

-is generally divided into older, thicker continental crust and younger, denser
oceanic crust.

is the outer layer of the Earth. It is a thin layer between 40 – 60 km thick.

its lightest, most buoyant rock layer. Continental crust covers 41
percent of the Earth’s surface, though a quarter of that area is under the oceans.

Answer 4

EARTH CRUST

Question 5

convergent boundaries occur when a tectonic plate primarily composed of oceanic lithosphere collides with a plate with continental lithosphere. Oceanic crust is much thinner, averaging about
6 km (4 miles) in thickness.

Answer 5

OCEANIC-CONTINENTAL

Question 6

occur when a tectonic plate primarily composed of oceanic lithosphere collides with a plate with continental lithosphere

Answer 6

convergent boundaries

Question 7

is typically 40 km (25 miles) thick continental crust, the outermost layer of
Earth’s lithosphere makes up the planet’s continents and continental shelves and formed near subduction zones at plate boundaries between continental and oceanic tectonic plates.

Answer 7

CONTINENTAL CRUST

Question 8

sits between Earth’s dense, very hot core and its thin outer layer, the crust

plays an important role in the evolution of the crust and provides the thermal
and mechanical driving forces for plate tectonics.

is about 2,900 kilometers (1,802 miles) thick, and makes up a whopping 84
percent of Earth’s total volume.

Answer 8

MANTLE

Question 9

extends from the crust to a depth of about 410 kilometers (255 miles).

mostly solid, but its more malleable regions contribute to tectonic activity.
Two parts of the upper mantle are often recognized as distinct regions in Earth’s interior: the
lithosphere and the asthenosphere.

Answer 9

UPPER MANTLE

Question 10

The lower level of the mantle, it is softer and weaker, particularly in its upper portion where a small amount of melting can occur.

Answer 10

asthenosphere

Question 11

The lower level of the mantle, it is softer and weaker, particularly in its upper portion where a small amount of melting can occur.

extends from about 660 kilometers (410 miles) to about 2,700 kilometers
(1,678 miles) beneath Earth’s surface.

is hotter and denser than the upper
mantle and transition zone. The lower mantle is much less ductile than the upper mantle and
transition one.

Answer 11

LOWER MANTLE

Question 12

starts around 5,000 km below the surface of the planet, and is thought to be
made of solid iron and nickel, due to the extreme pressure forcing the atoms of the metal to
pack together.

Answer 12

inner core

Question 13

is made of two layers: the outer core, which borders the mantle, and the inner core.
The boundary separating these regions is called the Bullen discontinuity.

is responsible for the generation of Earth’s magnetic field.

contains information regarding the earliest history of accretion of the planet.

Answer 13

CORE

Question 14

about 2,200 kilometers (1,367 miles) thick, is mostly composed of liquid iron and
nickel. The NiFe alloy of the outer core is very hot, between 4,500° and 5,500° Celsius (8,132° and
9,932° Fahrenheit).

Answer 14

OUTER CORE

Question 15

is a hot, dense ball of (mostly) iron. It has a radius of about 1,220 kilometers (758 miles).
Earth’s inner core is as hot as the surface of the sun—about 10,000oF (5,500oC). Also, inner core is
solid metal

Answer 15

INNER CORE