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Not Just Rocks: The Geology Quiz
by Staff
Geologists study the processes and substances that form Earth. Most of those processes happen over millions of years, but this quiz only takes a few minutes! Find out how rock solid your knowledge of geology is.

The part of Earth that lies just beneath the crust is the …

  • tectonic plate
  • mantle
  • ionosphere

Areas known as karst are characterized by extensive cave systems and are commonly associated with what type of rock?

  • limestone
  • sandstone
  • marble

How old is Earth?

  • 4.54 billion years
  • 430 million years
  • 80 trillion years

Moraines are geologic features that can form ridges, rolling hills or wedge-shaped areas. What process causes them to form?

  • the collision of two tectonic plates
  • the compression of sedimentary layers
  • glaciers depositing debris as they advance, melt and retreat

What U.S. state was formed by a hotspot of magma that was fed to the crust from the mantle?

  • Alaska
  • California
  • Hawaii

What sedimentary rock is formed when plant matter is buried and compressed over millions of years?

  • coal
  • sandstone
  • turbidite

What is the Ring of Fire?

  • a circular area of intense heat that forms around the cones of volcanoes
  • an area around the perimeter of the Pacific Ocean characterized by frequent, intense seismic activity
  • a region in Siberia where surface coal deposits are constantly burning

How do geologists think Earth's moon formed?

  • It formed as the result of a massive impact on Earth.
  • It formed from several asteroids millions of years after Earth formed.
  • It was one of Saturn's moons, but a collision knocked it out of orbit, and it was later captured by Earth's gravity.

What effect has erosion had on Niagara Falls?

  • It has caused the waterfall to retreat more than 10 kilometers (6.2 miles) in the last 10,000 years.
  • It has forced the river into a narrower passage by carving into the bedrock.
  • It has increased the velocity of the water by carving a deeper slope.

How does beach sand form?

  • petrification of topsoil
  • compression of volcanic rocks
  • ocean waves grind rocks into tiny grains over an extremely long time

What causes geysers?

  • an underground river causes pressure to back up in a constrained chamber
  • groundwater heated by magma becomes superheated and flashes into steam
  • a shifting fault pressurizes an underground chamber of water

How deep is the deepest man-made borehole on Earth?

  • 12,262 meters (40,230 feet)
  • 34,650 meters
  • 7,892 meters

Earth's continents were once joined as a single massive supercontinent. What do geologists call it?

  • Greater Eurasia
  • Pangaea
  • C-1

As you go deeper into Earth, the temperature …

  • gets hotter
  • gets cooler
  • varies from one layer to the next

The subduction of the Pacific Plate beneath the Mariana Plate caused the formation of what unique geologic feature?

  • Japan
  • the Mariana Trench
  • the Grand Canyon

How have seismologists mapped Earth's interior?

  • They infer the contents of the interior based on computer analysis of satellite images.
  • They use extremely strong radar waves.
  • They can see different types of waves from earthquakes propagate through areas of different density within the interior.

What type of rock is formed by extreme pressure and heat over a long time?

  • igneous
  • metamorphic
  • sedimentary

One type of rock can only be formed from the sudden shock and heat of a meteorite impact. What is it called?

  • impactite
  • schist
  • dolomite

Which of these is NOT a mineral?

  • Pyrex
  • asbestos
  • lead

Which of these is a type of lava flow?

  • pahoehoe
  • phyllite
  • shale

Uncemented sediments can form islands along ocean shorelines. What are these islands called?

  • atolls
  • barrier islands
  • sea mounts

Soil that does not match the age or composition of the underlying bedrock it sits upon is called …

  • residual soil
  • transported soil
  • compound soil

Which mineral precipitates from oceans and forms rock salt?

  • halite
  • quartz
  • olivine

What shape is Earth?

  • an oblate spheroid
  • a perfect sphere
  • pear-shaped

What is post-glacial rebound?

  • when the crust gradually lifts back up after being depressed by the incredible weight of glacial ice
  • when a glacier melts but quickly reforms
  • when the movement of a glacier is redirected by a pre-existing rock feature.

What causes Earth's magnetic field?

  • radiation from the sun
  • the alignment of magnetic metals in the crust
  • the movement of liquid iron in the outer core

A widely accepted theory suggests that mass extinctions have been caused by asteroid impacts. What evidence is there to support this theory?

  • remnants of massive impact craters on the surface
  • mountains which are actually intact asteroids sitting on the surface
  • cave paintings depicting massive spheres of fire falling from the sky

What is notable about the mineral called cinnabar?

  • It tastes like cinnamon.
  • It's the deadliest mineral on Earth.
  • It burns so slowly that a small chunk would sustain a flame for 15 years.

What is happening to the crust at the Mid-Atlantic Ridge?

  • It's colliding and forming a new chain of mountains.
  • It's spreading at a rate of approximately 2.5 centimeters each year as tectonic plates move away from each other.
  • It's relatively static.

What happened to Lake Missoula 15,000 years ago?

  • It was cut off from its source, and it dried up.
  • Fissures in the lake bed caused it to slowly drain into the groundwater.
  • The collapse of an ice dam caused it to catastrophically flood the surrounding area.