3 - SOLID EARTH/LITHOSPHERE Flashcards
It includes all of space, and all the matter and energy that space contains.
Universe
the leading explanation about how the universe began.
Big Bang Theory
o The universe began about _____ years ago.
13.8 billion
a large group of stars, gas, and dust bound together by gravity.
Galaxy
the galaxy in which Earth resides.
Milky Way Galaxy
our Milky Way’s closest neighbor. The closest large galaxy to Earth, is 2.5 million light-years away.
Andromeda Galaxy
the distance light travels in one Earth year.
light-year
- A star is formed as a cloud of dust and gas in space, called a ______, coalesces by mutual gravitational attraction and collapses.
nebula
- As the mass of this _____ increases, its internal pressure and temperature rise through gravitational compression.
protostar
o Not all the dust and gas in a nebula coalesces into the growing star. It also coalesces into smaller bodies that are not massive enough to trigger _______, resulting in the formation of planets, asteroids, and other objects.
nuclear fusion
o Our solar system and everything in it, including Earth, is formed from the coalescence of dust and gas about ____ years ago.
4.6 billion
a giant cloud of dust and gas in space.
nebula
the second stage of a newborn star in a nebula.
protostar
made up of the sun and everything that orbits around it, including planets, moons, asteroids, comets and meteoroids.
solar system
the star around which Earth and the other components of the solar system revolve.
- Sun
- The Sun is ____ the mass of Earth. The mass of the Sun exerts a strong gravitational pull that keeps the planets locked in their respective orbits along a flat plane.
333,000 times
Science of the solid Earth.
GEOLOGY
organization of Earth history into major units of eons, eras, and periods.
- Geologic Time Scale
organization of Earth history into major units of eons, eras, and periods.
- Geologic Time Scale
The ______ marks the beginning of widespread life on Earth.
Cambrian period
ü Largest unit of geologic time.
ü Including hundreds of millions of years; subdivided into eras.
Eon
ü Major unit of geologic time.
ü Tens or hundreds of millions of years in length; subdivided into periods.
Era
ü Unit of geologic time.
ü About tens of millions of years in length; subdivided into epochs
Period
The name given for the first super eon of Earth’s history.
Lasted from the first formation of the planet (about 4.6 billion years ago)
Precambrian
PRECAMBRIAN’S THREE EONS
Hadean Eon
Archean Eon
Proterozoic Eon
Earth’s initial formation
Hadean Eon
Formation of Earth’s crust
Archean Eon
Multicellular life
Proterozoic Eon
The eon of visible life.
Phanerozoic
ERA
Paleozoic
Mesozoic
Cenozoic
Old life
Includes early land plants, insects, reptiles, and amphibians
Paleozoic
Old life
Includes early land plants, insects, reptiles, and amphibians
Paleozoic
Middle life
Dominated by the dinosaurs.
Mesozoic
Recent life
Plants and animals look most like those on Earth today.
Cenozoic
Tertiary Period
Paleogene Period
Neogene Period
Quaternary Period
The beginning of the Cenozoic era
- dinosaurs, pterosaurs, and giant marine reptiles were conspicuously absent from the face of the Earth.
Paleogene Period
______ means “new born”
- Mountains rose, and sea levels fell. The climate cooled and dried.
Neogene Period
Characterized by the expansion and contraction of ice sheets in predictable cycles.
Quaternary Period
unit of geologic time up to tens of millions of years in length; a subdivision of the period time unit.
Epoch
EPOCH
Pleistocene Epoch
Holocene Epoch
Anthropocene Epoch
The Ice Age
Epoch of the Cenozoic Era
Pleistocene Epoch
Time since the end of the last major glacial epoch. The _____ has been a relatively warm period in between ice ages.
Holocene Epoch
An unofficial unit of geologic time, used to describe the most recent period in Earth’s history when human activity started to have a significant impact on the planet’s climate and ecosystems.
Anthropocene Epoch
Three major compositional layers of the Earth:
Core
Mantle
Crust
Spherical central mass of the Earth. It composed largely of iron and consisting of an outer liquid zone and an interior solid zone.
- Core
The inner part of the Earth’s core. consists of solid iron and nickel.
o Inner Core
The outer part of the Earth’s core. consists of molten iron and nickel.
o Outer Core
Rock layer or shell of the Earth beneath the crust and surrounding the core. It composed of ultramafic igneous rock of silicate mineral composition.
- Mantle
Outermost solid shell or layer of the Earth. It composed largely of silicate minerals.
- Crust
The Structure of the Earth
Lithosphere
Continental Crust
Oceanic Crust
Mohorovicic discontinuity or Moho
Asthenosphere
Seismic Waves
The outer, solid part of Earth.
Lithosphere
Granitic part of the Earth’s crust that makes up the continents.
Continental Crust
Basaltic part of the Earth’s crust that makes up the ocean basins.
Oceanic Crust
The boundary that separates the crust from the lithospheric mantle; seismic waves change speed at this boundary.
Mohorovicic discontinuity or Moho
The layer of very soft rock that occurs in the upper part of the upper mantle.
Asthenosphere
Vibrations that travel through the Earth when stress is released in an earthquake.
Seismic Waves
FORCES OF GEOLOGIC CHANGE
Endogenic Processes
Exogenic Processes
Internal Earth processes, such as tectonics and volcanism, that create landforms.
- Endogenic Processes
landform-making processes active at the Earth’s surface, such as erosion by water, waves and currents, glacial ice, and wind.
Exogenic Processes
the body of knowledge about lithospheric plates and their motions.
- Plate tectonics
a sudden shaking of the ground caused by movements of Earth’s crust.
- Earthquake
a fracture or zone of fractures between two blocks of rock.
Fault
the point on the Earth’s surface that lies directly over the focus of an earthquake.
- Epicenter
TYPES OF FAULTS
Normal Fault
Reverse Fault
Strike-slip Fault
Overthrust Fold
A steeply inclined fault in which the hanging rock block moves relatively downward.
Normal Fault
A steeply inclined fault in which the hanging rock block moves relatively upward.
Reverse Fault
A structural fault along which two lithospheric plates or rock blocks move horizontally in opposite directions and parallel to the fault line.
Strike-slip Fault
A structural feature where one part of the rock mass is shoved up and over the other.
Overthrust Fold
happen when lava and gas are discharged from a volcanic vent.
Volcanic eruptions
Hot molten rock that spills onto the surface of Earth’s crust.
- Lava
Melted rock that is below the surface of Earth’s crust.
- Magma
are long, narrow depressions on the seafloor.
- Ocean trenches
deepest of the world’s deep-sea trenches.
- Mariana Trench (Marianas Trench)
a path along the Pacific Ocean characterized by active volcanoes and frequent earthquakes.
The Ring of Fire
o Also referred to as the Circum-Pacific Belt.
The Ring of Fire
A large ocean wave triggered by an earthquake or other natural disturbance.
- Tsunami
The amount of energy released by an earthquake.
- Magnitude
naturally occurring, inorganic substances, often with a crystalline structure; they are largely composed of oxygen, silicon, aluminum, iron, calcium, sodium, potassium, and magnesium.
- Minerals
are naturally occurring assemblages of minerals.
- Rocks
Rocks’ three major classes:
Igneous rocks
Sedimentary rocks
Metamorphic rocks
are largely composed of silicate minerals. ex: Basalt
o Igneous rocks
are formed in layers, or strata, composed of transported rock fragments called sediment. ex: coal
o Sedimentary rocks
are formed when igneous or sedimentary rocks are exposed to heat and pressure. ex: marble
o Metamorphic rocks
natural feature, such as a hill or valley, on the surface of Earth.
- Landform
large landforms that rise high above surrounding terrain and usually form sharp peaks.
- Mountains
large, flat pieces of land with no drastic changes in elevation.
- Plains
an elevated piece of land that, unlike a mountain, is flat.
- Plateau
elevated sections of land with notable summits that are lower and less steep than mountains.
- Hills
a theory proposed by Alfred Wegener stating that continents move slowly across Earth’s surface.
- Continental Drift
the hypothetical supercontinent, composed of all the present continents, that existed between 300 and 200 million years ago.
- Pangaea