Geology Chapter 8 (2)
The Precambrian consists of the Archean and ________ Eons.
Proterozoic
________ are chunks of rock from the Solar System that reach the Earth's surface.
meteorites
________ are "shooting stars." The glow comes from small particles of rock from space being heated as they enter Earth's atmosphere.
meteors
The Solar System is part of the ________ ________ galaxy
milky way
The ________ may have formed as a result of an impact of a large body with Earth about 4.4 billion years ago. Debris from the impact was thrown into orbit around Earth and collected to form the ________.
moon
The basic idea that the sun and planets formed from the same cloud of gas and dust in interstellar space.
nebular hypothesis
The gases that formed Earth during accretion, reached the Earth's surface through a process called ________.
outgassing
The release of water vapor and other gases from Earth through volcanic activity is known as ________.
outgassing
Earth's first, primitive atmosphere lacked free ________.
oxygen
The earth's early atmosphere lacked which significant element present today?
oxygen
The Milky Way galaxy is part of the ________.
universe
Mercury, Venus, Earth, Mars are ________ planets
Terrestrial
________ are substances easily driven off by heating.
Volatiles
The sun's energy comes from nuclear ________, which involves hydrogen atoms changing into helium and releasing energy.
fusion
The Universe hosts billions of ________.
galaxies
________ are rapidly moving apart (Hubble's Law).
galaxies
A ________ is an aggregate of stars, planets, dust, and gases.
galaxy
Less dense, sialic (silicon- and aluminum-rich) continental crust dominated by ________.
granite
One reason that we believe that the early atmosphere was anoxic is that we do not find oxidized ________ in the early rock record.
iron
Jupiter, Saturn, Uranus, Neptune are ________ planets.
jovian
Outer, ________ planets have low density.
jovian
________ planets are large gaseousos and have low density.
jovian
Calculations indicate that the Big Bang occurred ________-________ billion years ago.
18-15
The earliest evidence of life occurs in Archean sedimentary rocks that are about ________ billion years old.
3.5
Felsic crust began forming around ________ billion years ago.
4.4
The first mafic, oceanic crust formed about ________ billion years ago by partial melting of rocks in the upper mantle.
4.5
Moon rocks and meteorites are as old as ________ billion years.
4.6
The Solar System is about ________ billion years old.
4.6
The ________ Eon began 4.6 bya and ended 2.5 bya.
Archean
Earth's oldest rocks are found in ________. They are about 4.04 billion years old.
Canada
There is an asteroid belt with thousands of asteroids, primarily between ________ and ________.
Mars and Jupiter
What are the names of the 9 planets, in order, from the sun outward. M V E M J S U N P - (My very elegant mother just sent us nine pizzas).
Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune Pluto
The ________ ________ gives an explanation for the formation of our solar system.
Nebular Hypothesis
What are the two types of the Earth's crust today?
Oceanic and Continental
The moon's dominant rock type is ________.
anorthosite
Dense, mafic (magnesium- and iron-rich) oceanic crust dominated by ________.
basalt
Precambrian rocks are frequently referred to as "________" rocks because they lie beneath a covering of fossil-bearing sedimentary strata.
basement
The Universe is expanding. Everything began together at a point. A big explosion occurred, which astronomers call the ________ ________. This explosion caused everything in the Universe to begin moving rapidly apart.
big bang
The ________ ________ is how we refer to the instaneous creation of all matter in the Universe.
big bang
The ________ ________ marked the instantaneous creation of all matter in the Universe.
big bang
The oldest known rocks of the Archean were found in ________, and the oldest mineral grains were found in Australia.
canada
Earth's primitive atmosphere was derived from gases associated with the ________ and ________ which formed the Earth during accretion.
comets and meteorites
The early-melting, less dense components of the partially melted crust rose to the surface where it cooled to form ________ ________.
continental crust
Planets revolve around the sun in what same direction?
counter clock wise
Felsic crust formed in subduction zones where descending slabs of ________ partially melted.
crust
The outer planets are gaseous and therefore less ________ than the inner planets.
dense
The earth's internal layered structure is believed to have formed from primary or secondary ________ , happening either during or after accretion.
differentiation
Planet Earth orbits the Sun, a ________ star, that belongs to the Milky Way galaxy.
dwarf
Planets lie roughly within sun's ________ plane (plane of sun's rotation).
equatorial
The development of the ________ cell, which led to a dramatic increase in the rate of evolution, occurred as oxygen became more readily available in the atmosphere.
eukaryotic
Earth's atmosphere has ________ or changed over time.
evolved
Continental crust developed after the initial mafic to ultramafic crust. Continental crust is sialic or ________ (such as granite).
felsic
Precambrian rocks are often inaccessible, deeply buried, poorly exposed, or have undergone significant changes, so we do not have as much data for this early geologic time. Additionally, Precambrian rocks contain very few ________ to help us understand life during the time.
fossils
Sun's energy comes from ________, a thermonuclear reaction in which hydrogen atoms are fused together to form helium, releasing energy.
fusion
A shift toward longer wavelengths of the spectral lines emitted by a celestial object. Caused by the object moving away from earth.
red shift
The ________ ________ indicates that the universe is expanding.
red shift
The Earth is part of the ________ ________.
solar system
The Sun and the planets, moons, asteroids, comets and other objects that orbit it, comprise the ________ ________.
solar system
The ________ ________ is disk-like in shape.
solar system
The Sun is a ________.
star
Felsic crust formed in ________ ________ where descending slabs of crust partially melted.
subduction zones
Distribution of planet densities and compositions is related to their distance from ________.
sun
Most matter contained in our solar system is contained within the ________.
sun
Inner, ________ planets have high density.
terrestrial
________ planets are small and dense.
terrestrial
