SCIENCE FINAL (GOOD LUCK!) Flashcards
U-235 decays into Pb-207. It has a half-life of 700 million years. How much U-235 of a 500g sample will remain after 1400 million years?
125 grams (500/2=250/2=125)
Why is GPS data useful in monitoring plate movement?
It’s able to detect movement in the crust
Are Earth’s tectonic plates moving now? Have they moved in the past? How do we know?
The plates have been moving for millions of years and are still moving today. We know this because of GPS data, geologic makers, and earthquakes, etc.
Differentiate between a meteor, meteorite, and a meteoroid.
Meteoroids are in space, meteors are in the atmosphere, and meteorites are on Earth
Why are meteorites considered sources of valuable scientific information?
Because they are formed out of the same material that the solar system is made of and that is useful for dating
What is the formula for Kepler’s third law?
P2=A3 (Orbital period (P) to average distance (A))
What are some factors that can determine the amount of damage a building will incur during an earthquake?
distance from the earthquake, how strong the earthquake is, the earthquake duration, building materials
How do buildings built on loose ground tend to do during earthquakes?
They do not do well and will almost always fall over
What is the thickest layer of the Earth?
Mantle
What cyclical motion in the mantle causes the tectonic plates to move, forces on the lithosphere, and heat transfer?
Mantle convection
According to the solar nebula condensation theory, what did the solar system form from?
The remnants from a supernova explosion
How long ago did the big bang occur?
13.8 billion years ago
GPS data on either side of a north-south trending fault show a 34.1 mm/year northerly movement for the east side and a 34.8 mm/year northerly movement on the west side. This measured movement indicates what type of plate boundary?
Transform
Millions of years from now, what will happen to the distance between North America and Europe? Why?
They will move further apart because they are divergent (←→) plate boundaries
Name and describe the 3 types of plate boundaries. Be able to identify them on a map that has arrows to indicate relative plate movement.
There is convergent (→←), divergent (←→), and transform boundaries (↑↓)
What drives tectonic plate movement?
Convection currents which is caused by changes in heat
Where on Earth is new crust formed? Old crust destroyed?
New crust is formed along divergent plate boundaries, and old crust is destroyed in subduction zones
What are the highest mountains on Earth? How did they form?
The Himalayan Mountains. They formed from 2 continental convergent plate boundaries (Eurasian and Indian plate)
Why does California have a lot of earthquakes?
It is along a transform fault boundary
What material can S waves not travel through?
Liquid (outer core)
Are rocky, Earth-like planets considered terrestrial or Jovian?
Terrestrial
What is a hypocenter/Focus?
The hypocenter is the the epicenter of the earthquake along with its depth
What happens to a planet’s orbital speed as it gets closer to its central star?
It moves faster
What layer of the Earth is part crust and part mantle?
Lithosphere
What shape do all of our planets have as they orbit the sun?
Ellipse
What event created the heavy elements found on Earth?
Supernova
Where are all elements heavier than hydrogen created?
Stars
Where did most of the Hydrogen in the universe come from?
The Big Bang
If a sample has undergone one half-life, what percentage of the original radioactive isotope remains?
50%
Draw an ellipse with low and high eccentricity.
◯ = low ⬯ = High
Compare the strength of a 5.0 and a 7.0 magnitude earthquake.
A 7.0 is 100 times (10*10) stronger than a 5.0
Name 3 things that can be observed at the surface near a transform fault.
There are big cracks and things that once lined up (like fences) no longer line up, crack buildings
What is the most important factor that determines how long a star will undergo fusion?
It’s mass
What is the Earth’s inner core composed of?
Solid nickel and iron
What part of the USA is most geologically active? Why?
Alaska because is is a convergent plate boundary
What layer of the Earth can most earthquakes be found?
Lithosphere
Using Kepler’s law, determine the orbital period of a planet that has a semimajor axis of 4 AU.
8 years (P2=(4)^3 P2=64 P=√64 P=8)
Where is most of the mass in our solar system found?
The sun
If you are viewing spectral line images, how can you determine if one element is heavier than another?
How many lines it has (the heavier, the more lines)
What general type of rock will contain fossils?
Sedimentary
Why do gas giants and ice giants typically not exist close to their central star?
They need to be cold in order to form
How does the lithosphere compare to the asthenosphere in terms of temperature and rigidity?
The Lithosphere is colder and more ridged. The asthenosphere is hotter and more flexible
What happens to the plates involved in a subduction zone?
The denser one will slide underneath the the less dense one
What key process causes a star to begin to “shine”?
Nuclear fusion
What will determine the properties of a mineral?
The atom and its atomic stucture
What determines if you have a trench or a mountain range at a convergent boundary?
Density difference
What instrument records earthquakes?
Seismometer
Why can meteorites be used to estimate the age of the Earth?
They contain minerals from the formation of the earth
What determines if a rock is classified as igneous, sedimentary, or metamorphic?
How it formed
Why are 3 seismometers needed to locate the epicenter of an earthquake?
The time difference between P and S wave arrival in a seismograph only tells you how far away the earthquake is. You need three distances to triangulate the epicenter
Why is spectroscopy useful in identifying temperature and composition of a planet?
Planets reflect starlight
Where do most earthquakes occur?
Along fault line/plate boundaries
What elements are created in supernovas?
Every element
What will determine the hardness, cleavage, and crystal shape of a mineral?
The crystal structure/Internal atomic structure
What is the underlying cause of continental drift?
Convection in the mantle
What type of rock forms when lava cools?
Igneous rocks
What determines if one mineral will scratch another?What scale is used for this?
The mineral’s hardness. This is called the Mohs scale
What 2 elements were created during the big bang?
hydrogen and helium
What are some sources of data about earthquakes?
GPS data, photographs, geologic markers, etc.
What is the age of the planets in our solar system relative to one another?
They are all the relatively the same age
Why are there so many volcanoes along the Pacific ring of fire?
Because that area has lots of subduction zones
What has to be done to layers of sand for it to form sandstone?
It was buried and subjected to compaction and cementation
Why do minerals have a characteristic shape even though they are formed at different times in different locations?
They have a similar atomic structure
Name 3 properties of minerals that can be used to identify them.
Color, streak, cleavage, hardness, fracture, reaction to acid
What stage of life do all stars experience?
Protostar
What is the solar nebula condensation theory?
The idea that the solar system formed from a spinning nebula
How is energy dissipated when large masses of rock move?
Earthquake/ seismic waves
Name 3 things that can be found in our solar system
Sun,planets, comets, etc.
Where do we think the planets in our Solar system came from?
Solar nebulas
How can you determine the distance to an epicenter by analyzing a seismograph?
The difference in the arrival time of P and S waves
What is the greatest source of information when studying the interior of the Earth?
Seismic waves
What type of rock is formed under great heat and pressure?
Metamorphic
How deep do the Earth’s plates go down from the surface of the Earth?
≈100 km
What are Kepler’s 3 laws of motion?
P 2 = a 3 , where P is the orbital period of the planet in years and a is the average distance of the planet from the central star in astronomical units (AU).
A planet orbits the Sun in an ellipse, with the Sun at one focus of the ellipse.
A line connecting a planet to the Sun sweeps out equal areas in equal time intervals.
Where would you look for a dense, rocky planet if you were looking for one around a nearby star?
Planets closer to the central star
What gives quartz its characteristic shape?
It’s internal atomic structure
What is created by a sudden release of pressure along a fault?
Earthquake
What type of plate boundary produces the largest earthquakes?
Convergent boundary
Why does Mars appear red in color?
It reflects red light
What are the final life stages of low mass, sun-like stars?
It forms a red giant then a planetary nebula with a white dwarf
How are diamond and graphite similar? How are they different?
They are both made of carbon, but they have different crystal structures
What type of rock will be formed as mud from a river is buried and cemented together?
Shale (Sedimentary)
What are the layers of the Earth?
Crust, Lithosphere, Asthenosphere, Mantle, Outer Core, and Inner Core
Will our sun explode in a supernova? Why?
No. It is not big enough
What is a half-life?
The time it takes for half of the nuclei in a sample of a radioactive isotope to decay
How can two rock outcrops with very similar characteristics be useful when studying plate tectonics?
They can be used to determine the rate and direction of fault motion
What variables increase with depth within the Earth?
temperature, density, pressure
What gets emitted by an atom as electrons move from higher energy levels to lower energy levels?
Light
What type of plate boundary tends to have small, shallow earthquakes?
Divergent boundaries
What is the problem with unreinforced concrete when it is put under stress by an earthquake?
It cannot withstand shear forces and crumbles which can result in building collapse
Why is the chance of a large earthquake in Waterford minimal?
We are in the middle of a plate, and most earthquakes occur along the edge of the boundary
What are the sources of heat that keep the core of the Earth warm?
Radioactive decay and remnants from the Earth’s formation
What gets created as pieces of a comet break off and cruise around space?
Meteoroid
What do we call small pieces of rock and dust that hit the atmosphere at speeds up to 70km/2 and burn up in the atmosphere?
Meteors
What occurs when the Earth travels through the debris trail of a comet?
Meteor showers
What is the approximate age of the sun?
4.6 billion years
Why are comets sometimes called “dirty snowballs”
Because they are made of ice and rock
What is the largest planet in our solar system?
Jupiter
Why is Venus so hot?
It has a CO2 atmosphere, which traps heat
What planet do we know has liquid water on its surface? Do we know of any others?
Earth is the only known planet with liquid water on its surface
Name the planets from the sun outward.
Mercury,Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
When are the sun’s most direct rays at the northernmost location?
June 21st (Summer solstice)
What is the difference between rotation and revolution?
Rotation = spinning. Revolution = moving around the sun in an elliptical orbit
What is molten rock above the surface of the Earth called? Beneath the surface?
When it’s above the surface it’s called lava, when it’s below it’s called magma
Are P waves compressional waves or shear waves?
Compressional waves
What caused Mount Hood to form in Oregon?
Subduction and magma flow to the surface formed the stratovolcano
Draw a diagram of the rock cycle.
Diagram on study guide or you can look one up for reference
How are sedimentary rocks turned into sediments?
Erosion and weathering
How is limestone formed?
When calcium carbonate from organisms (shells) undergoes cementation and compaction
What type of rock is formed when sediments are pressed or cemented together, when water evaporates and leaves crystals behind, or when sediments form from a solution?
Sedimentary rocks
What shape do quartz crystals have?
Hexagonal
What does Mohs scale measure?
A mineral’s hardness
Where are most stars located on the H-R diagram?
Main sequence
What happens to a main sequence star when it runs out of hydrogen?
It will fuse other elements and become red giants
What color are the hottest stars? The coolest stars?
Hottest = blue Coldest=red
What element is produced by hydrogen fusion in the sun?
Helium
Why do faraway stars typically appear red in color? What is this evidence of?Where is our sun on the H-R diagram?
Red shift due to space expansion, evidence of the big bang
Where is our sun on the H-R diagram?
The main sequence
How do trenches form?
Typically by an oceanic plate subducting under a continental plate
What is the primary evidence we have that Earth has a liquid, outer core?
S waves and the shadow zone
How long does it take for Earth to rotate 360 degrees? Make one complete revolution?
24 hours to rotate 360° and 365 days to compete a full revolution
What causes day and night?
The earth’s rotation
What are index fossils and how are they used?
Index fossils are the remains of organisms that lived for a very short, specific amount of time. They can be used to date sediment layers.
What indications can be seen prior to a tsunami?
Water receding and earthquakes beforehand
Will volcanoes in the Cascades ever erupt again?
yes
You are examining layers of sediment in the Grand Canyon. How can index fossils, radioactive decay, and the law of superposition be useful for you?
They can be used to date the layers of sediment
What are the smaller components that make up rocks?
Minerals
According to the law of superposition, what is the age of the uppermost layer of sediment relative to the other layers?
The youngest
Note:
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