Questions and Answers 2025/2026 Solved
100% Correct
PART 1: WEATHERING & SEDIMENT FORMATION
Question 1
What are the three categories of sedimentary rocks based on their composition
and mode of formation?
A) Igneous, metamorphic, and volcanic
B) Clastic (detrital), chemical/biochemical, and organic
C) Limestone, sandstone, and shale
D) Felsic, intermediate, and mafic
Correct Answer: B
Rationale: Sedimentary rocks are divided into three categories depending on what
type of sediment(s) they are made of: (1) Clastic (or detrital), composed of clasts
(broken pieces) of other rocks; (2) Chemical and biochemical, formed by the
precipitation of ions; and (3) Organic, composed of organic materials .
Question 2
Which type of weathering physically breaks rock into smaller pieces without
changing its chemical composition?
A) Chemical weathering
B) Mechanical (physical) weathering
C) Biological weathering
D) Oxidation
Correct Answer: B
,Rationale: Mechanical weathering (also called physical weathering) occurs when
rock physically breaks into smaller pieces. Processes include frost wedging,
abrasion, and exfoliation. Chemical weathering involves chemical reactions that
alter or dissolve minerals .
Question 3
What type of weathering transforms existing minerals into new minerals and
releases ions into the environment?
A) Mechanical weathering
B) Physical weathering
C) Chemical weathering
D) Thermal weathering
Correct Answer: C
Rationale: Chemical weathering transforms existing minerals into new minerals
and releases ions into the environment through reactions such as hydrolysis,
oxidation, and dissolution. For example, hydrolysis turns plagioclase into kaolinite
clay .
Question 4
The process by which loose sediment is transformed into solid sedimentary rock is
called:
A) Weathering
B) Erosion
C) Lithification
D) Metamorphism
Correct Answer: C
, Rationale: Lithification is the process where sediments are compacted and
cemented together to form hard rock, encompassing both compaction and
cementation stages .
Question 5
Which two processes are involved in lithification?
A) Weathering and erosion
B) Compaction and cementation
C) Melting and cooling
D) Deposition and transportation
Correct Answer: B
Rationale: Lithification involves compaction (squeezing sediments under pressure
to reduce pore space) and cementation (dissolved minerals depositing in spaces
between sediments, binding them together) .
Question 6
What is the correct order of the processes that produce sedimentary rocks from
pre-existing rocks?
A) Erosion → Weathering → Deposition → Lithification
B) Weathering → Erosion → Deposition → Lithification
C) Deposition → Weathering → Erosion → Lithification
D) Lithification → Weathering → Erosion → Deposition
Correct Answer: B
Rationale: The correct sequence is weathering (breaking down rocks), erosion
(transport of sediments), deposition (sediments settle), and lithification
(compaction and cementation) .