Page 1 of 67
2026 GL101 EXAM REVIEW COMPLETE
QUESTIONS AND DETAILED CORRECT
(EXPERT VERIFIED) ANSWERS/TOP-RATED
A+.
GL101
Maximize your success on your GL101 (likely Introduction to
Geology or General Science) exam with this comprehensive
review that strengthens your understanding of Earth's materials,
geological processes, plate tectonics, and the rock cycle. It is
specifically designed for introductory science students to build
a solid understanding of geological principles and their
relevance to the natural world.
How do unconsolidated sediments originate?
A) by spontaneous decomposition in place of underlying
rocks
B) by weathering, erosion, transport, and deposition
C) from the rock cycle by interrupted transmission
D) from meteorite showers breaking up rocks .......
ANSWER ....... ✓ ✓ B
, Page 2 of 67
Which characteristic is absolutely necessary for a
sedimentary rock to have potential as a possible reservoir
rock for oil or gas?
A) high porosity
B) clastic texture
C) chemical origin
D) good stratification ....... ANSWER ....... ✓ ✓ A
What percentage of the Earth's crust is composed of
sedimentary rocks?
A) 5%
B) 15%
C) 25%
D) 75% ....... ANSWER ....... ✓ ✓ A
Which type of sediment undergoes the most compaction as
it lithifies to sedimentary rocks?
A) marine mud
B) desert dune sand
C) reef limestone
, Page 3 of 67
D) coarse gravel ....... ANSWER ....... ✓ ✓ A
What are the most common cementing agents in
sedimentary rocks?
A) CaO
B) Ca(OH)2
C) calcite, silica, and iron oxides
D) clays and bitumen ....... ANSWER ....... ✓ ✓ C
Which common mineral of igneous rocks is the most
abundant mineral in detrital sedimentary rocks?
A) calcite
B) orthoclase
C) quartz
D) biotite ....... ANSWER ....... ✓ ✓ C
________ cement produces dark red and orange colours in
some sandstone.
A) Clay
B) Calcite
, Page 4 of 67
C) Quartz
D) Iron oxide ....... ANSWER ....... ✓ ✓ D
Assume that water filling a crack in a rock undergoes cycles
of freezing and melting. Which of the following statements is
true?
A) Water expands as it melts, causing the crack walls to be
pushed apart.
B) Water shrinks as it freezes, causing the crack walls to be
drawn closer together.
C) Water expands as it freezes, causing the crack walls to be
pushed apart.
D) Water shrinks as it melts, causing the crack walls to be
pulled closer together. ....... ANSWER ....... ✓ ✓ C
Which of the following is/are most susceptible to chemical
weathering by dissolution?
A) quartz
B) clay minerals
C) iron oxides
D) calcite ....... ANSWER ....... ✓ ✓ D
2026 GL101 EXAM REVIEW COMPLETE
QUESTIONS AND DETAILED CORRECT
(EXPERT VERIFIED) ANSWERS/TOP-RATED
A+.
GL101
Maximize your success on your GL101 (likely Introduction to
Geology or General Science) exam with this comprehensive
review that strengthens your understanding of Earth's materials,
geological processes, plate tectonics, and the rock cycle. It is
specifically designed for introductory science students to build
a solid understanding of geological principles and their
relevance to the natural world.
How do unconsolidated sediments originate?
A) by spontaneous decomposition in place of underlying
rocks
B) by weathering, erosion, transport, and deposition
C) from the rock cycle by interrupted transmission
D) from meteorite showers breaking up rocks .......
ANSWER ....... ✓ ✓ B
, Page 2 of 67
Which characteristic is absolutely necessary for a
sedimentary rock to have potential as a possible reservoir
rock for oil or gas?
A) high porosity
B) clastic texture
C) chemical origin
D) good stratification ....... ANSWER ....... ✓ ✓ A
What percentage of the Earth's crust is composed of
sedimentary rocks?
A) 5%
B) 15%
C) 25%
D) 75% ....... ANSWER ....... ✓ ✓ A
Which type of sediment undergoes the most compaction as
it lithifies to sedimentary rocks?
A) marine mud
B) desert dune sand
C) reef limestone
, Page 3 of 67
D) coarse gravel ....... ANSWER ....... ✓ ✓ A
What are the most common cementing agents in
sedimentary rocks?
A) CaO
B) Ca(OH)2
C) calcite, silica, and iron oxides
D) clays and bitumen ....... ANSWER ....... ✓ ✓ C
Which common mineral of igneous rocks is the most
abundant mineral in detrital sedimentary rocks?
A) calcite
B) orthoclase
C) quartz
D) biotite ....... ANSWER ....... ✓ ✓ C
________ cement produces dark red and orange colours in
some sandstone.
A) Clay
B) Calcite
, Page 4 of 67
C) Quartz
D) Iron oxide ....... ANSWER ....... ✓ ✓ D
Assume that water filling a crack in a rock undergoes cycles
of freezing and melting. Which of the following statements is
true?
A) Water expands as it melts, causing the crack walls to be
pushed apart.
B) Water shrinks as it freezes, causing the crack walls to be
drawn closer together.
C) Water expands as it freezes, causing the crack walls to be
pushed apart.
D) Water shrinks as it melts, causing the crack walls to be
pulled closer together. ....... ANSWER ....... ✓ ✓ C
Which of the following is/are most susceptible to chemical
weathering by dissolution?
A) quartz
B) clay minerals
C) iron oxides
D) calcite ....... ANSWER ....... ✓ ✓ D
