Accretion Theory (Origin of the Planet Earth) Flashcards
What is the process of accretion?
The accumulation of small pieces of dust forms huge lumps of matter.
What is accretion based on astrology?
Gravity attracts tiny bits of matter toward an object. This
results in a gradual increase in the object’s size.
In relation to the solar system formation, the objects increase its size until it turn into planets and stars. This is because of the?
GRAVITATIONAL PULL
A protoplanet is a planetary embryo that consists of
collection of matter, from which a planet is formed.
TRUE!
What are the two hypotheses on how the structure of Earth was formed that both involve accretion?
HOMOGENEOUS ACCRETION HYPOTHESIS
HETEROGENEOUS ACCRETION HYPOTHESIS
What does the homogeneous accretion hypothesis state?
This states that the formation of Earth began AFTER!!!!!!!! the condensation of fine particles of the primitive nebula is about 4.6 billion years ago.
HOMO
When these particles accreted, they formed a HOMOGENEOUS primordial Earth. Thus, early Earth had a uniform ____ composition.
UNIFORM SOLID
HOMO
What were the primary components of the early Earth?
iron, magnesium, nickel, and silicates
radioactive elements: uranium and thorium
HOMO
Due to gravitational contraction and decay of radioactive
elements, the temperature of early Earth increased.
TRUE
HOMO
What elements melted that sank to the center and became the primary elements that compose the Earth’s core?
Iron and Nickel
HOMO
Less dense silicates were displaced and moved upwards.
TRUE
HOMO
It took many years for iron and nickel to accumulate and reach
the center of about 4000 miles deep.
TRUE
HOMO
Earth’s surface experienced turmoil, violent earthquakes, continual volcanic eruptions, and covering of the surface with flowing lava during the accumulation of iron and nickel.
TRUE
HOMO
After the cooling down of the early Earth, a thin layer of solid rock formed the ____, including the continental and ocean basins.
CRUST
HOMO
In between the core and crust is the mantle. What is the mantle made out of?
Semi-molten silicate rocks and other minerals.
What does the heterogeneous accretion hypothesis state?
This states that the core has formed at the same time as Earth. Therefore, early Earth had its basic layered structure with a core, mantle, and crust.
Earth accreted DURING!!!!!!!!!!!!!!!!!!! condensation, forming a differentiated planet as it grew in size.
HETERO
As the nebula cooled down, its particles have condensed
depending on their condensation points.
TRUE
Oxides of ALUMINUM and CALCIUM condensed first, followed by IRON and NICKEL.
ALuminum Calcium = ALUC -> ALOK
Iron Nickel = Ibigay ng Nanay
ALUC muna bago Ibigay ng Nanay
Oxides of ALUMINUM and CALCIUM condensed first, followed by IRON and NICKEL. When the nebula cooled further, the
SILICATES condensed.
- Aluminum and Calcium
- Iron and Nickel
- Silicates
TRUE
ALuminum Calcium = ALUC -> ALOK
Iron Nickel = Ibigay ng Nanay
Silicates = Saya Siya
ALoC muna bago Ibigay ng Nanay kaya Saya Siya
The CORE was developed by accretion of
Aluminum and Calcium Oxide, followed by Iron
and Nickel
TRUEG
ALoC muna bago Ibigay ng Nanay
The outermost layer is composed of ______, as
well as volatile particles including _____.
SILICATES, WATER
Who is the proponent of the Accretion Theory?
Otto Yulyevich Schmidt
SEQUENCES OF EVOLUTIONARY EVENTS IN ACCRETION THEORY ARE THE? (5)
Collapsing of molecular cloud
formation of the protoplanetary Disk
growth of Planetesimals
beginning to Orbit the central star
growth of protoplanet Earth
C D P O P
