Download Notes: Earth/Moon Formation 3/11

Notes: Earth/Moon Formation 3/11
Notes: Earth/Moon Formation 3/11
1. Explain the three sources of heat that contributed
to the high temperature of the newly formed
Earth. (p. 688).
The three sources of heat were
• Energy from the planetesimals that collided
• Increasing weight of outer layers compressed inner
layers
• Radioactive materials
#2. What is the process of differentiation?
#2. It is when denser materials, like molten iron,
sank to Earth’s center and less dense materials
were forced to outer layers, causing 3 distinct
layers.
#3. What elements make up the Earth’s
core? Mantle? Crust?
• The dense core is made of iron and nickel.
• The mantle is made of iron and magnesium-rich
rock.
• The crust is less dense, silica-rich rock.
#4. Why is the core of the Earth more
dense than the crust? What does this have
to do with differentiation?
The Earth was hot enough to melt iron. The dense,
molten iron sank to the center of the Earth. The less
dense elements were forced to outer surface. This is
called differentiation.
#5. How do scientists know the inner core is
solid and the outer core is liquid? (p. 298)
They measure P and S waves (seismic waves) and see the
Shadow Zones caused by the liquid outer core and solid
inner core.
#6. What is a crater?
A crater is a bowl-shaped depression.
#7. How is a crater formed?
A crater is formed when debris left over from the
formation of the solar system hits the surface of the
moon or planet.
#8. How does the composition of moon rocks compare
to the composition of the rocks found on Earth?
Moon rocks contain the same elements in different
proportions.
Lunar rocks are igneous, contain mostly O and Si.
Highland rocks are rich in Ca and Al, maria rocks
contain Ti, Mg, and Fe.
#9. How do scientists know about the
interior layering of the moon?
Seismographs have recorded moonquakes.
#10. How is the interior layering of the moon similar
to that of Earth? Different?
They are similar because the moon also has a crust,
mantle and core. The core is both liquid and solid.
They are different because the crust is thicker on one
side.
#11. What is the most accepted hypothesis
for the formation of the moon?
The Giant Impact Hypothesis is the most
accepted hypothesis.
It states that a Mars-sized body hit Earth, which
ejected chunks of Earth’s mantle into orbit
around the Earth. The debris came together to
form the moon.