CSET CSET Science: Earth and Space Sciences 1 — Questions and Answers
Question 1: Which layer of Earth is composed primarily of iron and nickel in a solid state?
- Inner core (Correct answer)
- Outer core
- Mantle
- Crust
Correct answer: Inner core
The inner core is solid iron and nickel because the immense pressure at Earth's center exceeds the melting point threshold, keeping it solid despite extremely high temperatures.
Question 2: What type of plate boundary is associated with the formation of mountain ranges like the Himalayas?
- Divergent boundary
- Transform boundary
- Continental-continental convergent boundary (Correct answer)
- Oceanic-continental subduction zone
Correct answer: Continental-continental convergent boundary
When two continental plates collide at a convergent boundary, neither subducts, so both plates crumple upward, forming mountain ranges like the Himalayas.
Question 3: The San Andreas Fault in California is an example of which type of plate boundary?
- Convergent boundary
- Divergent boundary
- Transform boundary (Correct answer)
- Subduction zone
Correct answer: Transform boundary
The San Andreas Fault is a transform boundary where the Pacific and North American plates slide horizontally past each other, generating frequent earthquakes.
Question 4: Which process is primarily responsible for the movement of tectonic plates?
- Gravitational pull from the Moon
- Convection currents in the mantle (Correct answer)
- Earth's rotation on its axis
- Solar radiation heating the surface
Correct answer: Convection currents in the mantle
Convection currents in the semi-fluid mantle, driven by heat from Earth's interior, create drag forces that move tectonic plates.
Question 5: Which type of rock forms from the cooling and solidification of magma or lava?
- Sedimentary rock
- Metamorphic rock
- Igneous rock (Correct answer)
- Clastic rock
Correct answer: Igneous rock
Igneous rock forms when magma (underground) or lava (at the surface) cools and crystallizes; the name derives from the Latin word for fire.
Question 6: Seafloor spreading occurs at which type of tectonic plate boundary?
- Convergent boundary
- Transform boundary
- Divergent boundary (Correct answer)
- Subduction zone
Correct answer: Divergent boundary
At divergent boundaries, tectonic plates move apart, allowing magma to rise and solidify, continuously creating new oceanic crust through seafloor spreading.
Question 7: Which evidence most strongly supports the theory of continental drift?
- Similar average ocean depths across all oceans
- Matching fossil records and rock formations on now-separated continents (Correct answer)
- Identical weather patterns on different continents
- Uniform magnetic field strength across Earth's surface
Correct answer: Matching fossil records and rock formations on now-separated continents
Matching fossil species and identical rock formations found on continents now separated by oceans indicate those landmasses were once connected.
CSET CSET Science: Earth and Space Sciences 1
Which layer of Earth is composed primarily of iron and nickel in a solid state?