ESS 101 A LAB 5: SEISMOLOGY AND
TECTONICS QUESTIONS AND
ANSWERS 2026/2027 UPDATE || 100%
GUARANTEED PASS
1. Which type of seismic wave is characterized by a compressional motion similar to a slinky
being pushed and pulled?
A. Love waves
B. Secondary waves
C. Primary waves
D. Rayleigh waves
Answer: C
Conceptual Explanation: Primary (P) waves are longitudinal waves that compress and
expand the material through which they travel, moving faster than other seismic waves.
2. The S-wave shadow zone exists because:
A. S-waves are reflected by the mantle-core boundary
B. S-waves cannot travel through the liquid outer core
C. S-waves travel too slowly to be detected on the far side of the Earth
D. S-waves are converted into P-waves at the Moho
,Answer: B
Conceptual Explanation: S-waves are shear waves and cannot propagate through fluids.
The liquid nature of the outer core prevents them from passing through to the opposite
side of the planet.
3. What is the minimum number of seismograph stations required to determine the exact
location of an earthquake’s epicenter?
A. Two
B. One
C. Four
D. Three
Answer: D
Conceptual Explanation: Triangulation requires at least three stations. The intersection of
three circles, each with a radius equal to the distance from a station to the epicenter,
identifies the unique point of the epicenter.
4. The point within the Earth where the actual rupture of rock occurs during an earthquake is
known as the:
A. Focus (Hypocenter)
B. Epicenter
C. Scarp
, D. Fault trace
Answer: A
Conceptual Explanation: The focus or hypocenter is the internal point of origin, while the
epicenter is the point on the Earth’s surface directly above it.
5. Which scale measures the total energy released by an earthquake based on the area of the
fault rupture and the amount of slip?
A. Moment Magnitude Scale
B. Modified Mercalli Scale
C. Richter Scale
D. Beaufort Scale
Answer: A
Conceptual Explanation: The Moment Magnitude Scale (Mw) is the most accurate for
large earthquakes as it accounts for the physical parameters of the faulting process, unlike
the Richter scale which is based on wave amplitude.
6. In the context of Elastic Rebound Theory, what happens to the rocks immediately before
an earthquake?
A. They store energy through elastic deformation
B. They undergo brittle failure immediately
C. They melt due to friction
TECTONICS QUESTIONS AND
ANSWERS 2026/2027 UPDATE || 100%
GUARANTEED PASS
1. Which type of seismic wave is characterized by a compressional motion similar to a slinky
being pushed and pulled?
A. Love waves
B. Secondary waves
C. Primary waves
D. Rayleigh waves
Answer: C
Conceptual Explanation: Primary (P) waves are longitudinal waves that compress and
expand the material through which they travel, moving faster than other seismic waves.
2. The S-wave shadow zone exists because:
A. S-waves are reflected by the mantle-core boundary
B. S-waves cannot travel through the liquid outer core
C. S-waves travel too slowly to be detected on the far side of the Earth
D. S-waves are converted into P-waves at the Moho
,Answer: B
Conceptual Explanation: S-waves are shear waves and cannot propagate through fluids.
The liquid nature of the outer core prevents them from passing through to the opposite
side of the planet.
3. What is the minimum number of seismograph stations required to determine the exact
location of an earthquake’s epicenter?
A. Two
B. One
C. Four
D. Three
Answer: D
Conceptual Explanation: Triangulation requires at least three stations. The intersection of
three circles, each with a radius equal to the distance from a station to the epicenter,
identifies the unique point of the epicenter.
4. The point within the Earth where the actual rupture of rock occurs during an earthquake is
known as the:
A. Focus (Hypocenter)
B. Epicenter
C. Scarp
, D. Fault trace
Answer: A
Conceptual Explanation: The focus or hypocenter is the internal point of origin, while the
epicenter is the point on the Earth’s surface directly above it.
5. Which scale measures the total energy released by an earthquake based on the area of the
fault rupture and the amount of slip?
A. Moment Magnitude Scale
B. Modified Mercalli Scale
C. Richter Scale
D. Beaufort Scale
Answer: A
Conceptual Explanation: The Moment Magnitude Scale (Mw) is the most accurate for
large earthquakes as it accounts for the physical parameters of the faulting process, unlike
the Richter scale which is based on wave amplitude.
6. In the context of Elastic Rebound Theory, what happens to the rocks immediately before
an earthquake?
A. They store energy through elastic deformation
B. They undergo brittle failure immediately
C. They melt due to friction
