geology multiple choice 2

What is the scientific method?

C. A systematic approach to answering questions through observation, experimentation, and reasoning

Which of the following is the correct order of the scientific method

B. Observation → Hypothesis → Experiment/Testing → Data Analysis → Theory

What does uniformitarianism state?

C. The present is the key to the past; Earth processes today also operated in the past.

How do geologists use uniformitarianism?

B. To compare ancient processes with modern ones to interpret Earth’s history

How old is the Earth?

C. 4.6 billion years

Which of the following are Earth’s four spheres?

A. Biosphere, Geosphere, Atmosphere, Hydrosphere

The biosphere includes:

C. Living organisms

What are the two main sources of Earth’s energy?

B. Solar energy and Earth’s internal heat

Which processes are driven by solar energy?

B. Weather and climate

Which processes are driven by Earth’s internal heat?

B. Rock cycle, volcanism, earthquakes

What does the Solar Nebular Hypothesis explain?

C. The formation of the solar system from a rotating cloud of gas and dust

What evidence supports the Solar Nebular Hypothesis?

B. Similar composition of meteorites and planets

How did the Moon form?

C. A Mars-sized body collided with Earth, and debris formed the Moon

About when did the Moon form?

B. 4.5 billion years ago

How did Earth separate into its compositional zones (core, mantle, crust)?

C. By density differentiation—heavier elements sank, lighter rose

Which feature makes Earth unique among the planets?

B. Presence of liquid water and life-supporting atmosphere

What is plate tectonics?

B. A theory stating that the Earth's surface is broken into plates that move

What source of energy drives plate tectonics, and how?

B. Earth’s internal heat

Which of the following did Wegener use to support his continental drift hypothesis?

D. All of the above

Why was Wegener’s hypothesis originally rejected?

B. He could not explain the mechanism for continental movement

What is the general concept of continental drift?

B. Continents slowly move over Earth’s surface

How does Hess’ seafloor spreading fit into continental drift?

A. It showed how new ocean crust forms at ridges and pushes continents apart

How does paleomagnetism support seafloor spreading?

A. record Earth’s magnetic field reversals in symmetrical stripes

What are the general characteristics of divergent boundaries?

A. Plates move apart

What are the general characteristics of convergent boundaries?

C. Plates collide

What are the general characteristics of transform boundaries?

A. Plates move horizontally

How does the mantle melt at divergent boundaries?

B. Decompression melting as plates pull apart

How does the mantle melt at convergent boundaries?

B. Addition of water from the subducting slab lowers melting temperature

Which is an example of a divergent boundary

A. Mid-Atlantic Ridge

Which is an example of a convergent boundary?

A. Himalayas

Which is an example of a transform boundary?

A. San Andreas Fault, California

Which of the following lists the five characteristics that define a mineral?

B. Naturally occurring, inorganic, solid, definite chemical composition, crystalline structure

What is the difference between a mineral and a rock?

C. Minerals are naturally occurring crystalline substances; rocks are aggregates of one or more minerals

Which type of bonding involves the transfer of electrons between atoms?

B. Ionic

Which type of bonding involves the sharing of electrons between atoms?

B. Covalent

Which type of bonding allows electrons to move freely, making minerals good conductors?

A. Ionic

Which type of bonding allows electrons to move freely, making minerals good conductors?

C. Metallic

Which of the following is not a physical property used to identify minerals?

D. Age

The Mohs scale measures a mineral’s:

C. Hardness

A mineral’s tendency to break along flat planes of weakness in its structure is called:

A. Cleavage

Which mineral class is the most abundant in Earth’s crust?

C. Silicates

What is an igneous rock?

B. A rock formed by the cooling and solidification of magma or lava

What is the most common class of minerals in igneous rocks?

B. Silicates

If magma generated in the mantle is basaltic (mafic), which processes can produce more felsic rocks like andesite or granite?

A. Crystal settling and partial melting of continental crust

What type of igneous rock is most common at a divergent margin (mid-ocean ridge)?

B. Basalt 

What type of igneous rock is most common at a convergent margin (subduction zone)?

B. Andesite

How does the presence of water affect the melting temperature of rocks?

B. Decreases melting temperature

How does increasing pressure affect the melting temperature of rocks?

A. Increases melting temperature

How does Bowen’s reaction series help us understand igneous rocks?

B. It explains the order in which minerals crystallize from cooling magma

In what plate tectonic settings are most of Earth’s volcanoes found?

B. At convergent and divergent boundaries

What is intraplate volcanism?

B. Volcanism within a plate, often caused by mantle plumes (hot spots)

Which volcano type is generally more destructive or hazardous?

B. Composite volcano, because it erupts explosively due to high viscosity magma

What were the three hypotheses proposed to explain the seismic activity before Pinatubo erupted?

A. (1) Earthquakes from tectonic stress, (2) Magma rising into the volcano, (3) Hydrothermal (steam-related) activity

How did volcanologists use earthquakes to study Pinatubo?

B. They tracked the depth and frequency of quakes to locate magma movement

What are the greatest hazards to humans during and after a volcanic eruption?

C. Pyroclastic flows, ashfall, lahars (mudflows), and long-term climate effects

What was Pangaea?

B. The most recent supercontinent that began breaking apart less than 200 million years ago

What did Alfred Wegener propose with his continental drift hypothesis?

B. Continents have moved relative to each other over Earth’s history

What occurs during seafloor spreading?

B. New oceanic crust forms at mid-ocean ridges and moves outward

What happens at a divergent boundary?

A. Two plates move apart

What is a mid-ocean ridge?

B. A divergent boundary between two oceanic plates

What is a continental rift?

A. A divergent boundary between two continental plates

What happens at a convergent boundary?

C. Two plates come together

What forms a continental volcanic arc?

A. Subduction of oceanic crust

What forms an island arc?

A. Subduction of oceanic crust

What is subduction?

B. oceanic plate descends beneath a less dense plate

What occurs at a transform boundary?

C. Plates slide past one another

What is the Ring of Fire?

B. A major area with earthquakes and volcanic eruptions

What is partial melting?

B. When only certain minerals in a rock melt

What is hydration melting?

C. Melting caused by adding water to the mantle

What is decompression melting?

B. Melting caused by pressure reduction

What is the rock cycle?

B. The process of rocks changing into igneous, sedimentary, and metamorphic types

How do igneous rocks form?

A. By cooling and solidification of magma or lava

How do sedimentary rocks form?

B. When sediments are pressed together over time

How do metamorphic rocks form?

C. By increased heat and pressure

What is the lithosphere?

B. The outermost layer of Earth, made of crust and upper mantle; forms tectonic plates

What is the asthenosphere?

B. A layer that drives plate motion

What is orogenesis process?

B. Plates crash and mountains form

Paleomagnetism is the study of what?

B. Earth's ancient magnetic field as recorded in rocks

What is magnetic striping on the ocean floor?

B. Ocean floor stripes show magnetic flips

What does the Big Bang theory propose?

C) Universe started with a giant explosion.

What does the Solar Nebular Hypothesis explain?

B) A nebula can collapse and form a star with planets

What does the Giant Impact Hypothesis suggest?

C) A large body struck Earth, ejecting material that formed the Moon

What is planetary accretion?

B) The process of solids accumulating into larger bodies, eventually forming planets

What is chemical differentiation in planetary bodies?

A) Materials separate into layers

Which is true about the Earth’s inner core?

B) It is solid and the innermost layer

Which describes the Earth’s outer core?

B) A liquid layer responsible for Earth’s magnetic field

What is the mantle made of?

C) Hot, solid rock between the crust and core

Which is true about oceanic crust?

B) Thin, basaltic, and denser than the upper mantle as it cools

Which is true about continental crust?

B) Thick, and less dense

What does the hydrosphere include?

C) Earth’s water in solid, liquid, and gas forms

What is the atmosphere mostly made of?

C) Nitrogen and oxygen gases

What does the biosphere consist of?

B) Living organisms on Earth

What does the geosphere include?

A) Earth’s crust, mantle, and core

What is convection?

B) Uneven heating in fluids

What is an igneous rock?

C) Rock formed through the cooling and solidification of magma or lava

What does “intrusive” mean in geology?

B) Igneous rock forming inside Earth beneath the surface

What does “extrusive” mean in geology?

B) Igneous rock forming on the surface

What is partial melting?

B) When only a portion of a solid rock melts

What is fractional crystallization?

A) Magma becoming felsic as mafic minerals crystallize during cooling

What is magma differentiation?

B) Changing a magma’s composition by assimilation or fractionation