Metamorphic Rocks and Processes
50 revision questions with answers for 1.4 Metamorphic Rocks and Processes in Eduqas GCSE Geology (spec C480QS). Practise with flashcards, a topic quiz, a random quiz across the course, 5 crosswords, Five Degrees, Associations, or read every question and answer below. Not official Eduqas material.
All 50 questions and answers
Question 1
What is metamorphism?
Answer:The alteration and recrystallisation of pre-existing rock due to increased temperature and/or pressure, without wholesale melting.Question 2
What is the parent rock, or protolith, of a metamorphic rock?
Answer:The pre-existing rock from which the metamorphic rock formed.Question 3
Does metamorphism require a pre-existing rock?
Answer:Yes. Any rock type can be altered by suitable temperature and pressure.Question 4
What happens to minerals during metamorphic recrystallisation?
Answer:Existing minerals change or reorganise and new mineral crystals may grow.Question 5
Why is a metamorphic rock not simply a solidified melt?
Answer:It forms mainly by solid-state change; crystallisation from a melt produces igneous rock.Question 6
What is contact metamorphism?
Answer:Alteration of country rock mainly by heat close to an igneous intrusion.Question 7
What is a metamorphic aureole?
Answer:The zone of altered country rock around an igneous intrusion.Question 8
Where is the greatest heating commonly found in a contact aureole?
Answer:Close to the intrusion's contact, where the country rock was nearest the heat source.Question 9
What is regional metamorphism?
Answer:Metamorphism affecting a broad area, usually involving increased pressure and temperature during mountain building.Question 10
Why can continental collision cause regional metamorphism?
Answer:Compression thickens and buries rocks, increasing pressure and temperature over a wide area.Question 11
What is foliation?
Answer:A planar arrangement or alignment of minerals or structures within a metamorphic rock.Question 12
How can directed pressure produce foliation?
Answer:Platy minerals grow or rotate into a preferred orientation under differential stress.Question 13
What is a non-foliated texture?
Answer:A texture without a consistent planar alignment of minerals.Question 14
What is slaty cleavage?
Answer:A fine planar splitting produced during metamorphism, allowing slate to split into thin sheets.Question 15
What is schistosity?
Answer:Foliation produced by visible aligned platy minerals, commonly mica, in schist.Question 16
How can you distinguish slate from schist in a hand specimen?
Answer:Slate is fine-grained with slaty cleavage; schist generally has visibly larger, aligned mineral flakes.Question 17
Why are mineral orientation and crystal size both useful for identifying metamorphic rocks?
Answer:They help distinguish fine or coarse and foliated or non-foliated textures.Question 18
What features should appear in a labelled sketch of schist?
Answer:Visible mineral crystals or flakes aligned in a common direction, with a scale.Question 19
What features should appear in a sketch of marble?
Answer:Interlocking calcite crystals without a strong preferred alignment, with a scale.Question 20
Why is foliation not the same thing as sedimentary bedding?
Answer:Foliation forms during metamorphism; bedding forms during sediment deposition.Question 21
Which sedimentary rock commonly metamorphoses into slate?
Answer:Shale.Question 22
What forms when limestone recrystallises during metamorphism?
Answer:Marble.Question 23
What forms when quartz sandstone recrystallises during metamorphism?
Answer:Metaquartzite.Question 24
What mineral is abundant in marble?
Answer:Calcite.Question 25
What mineral is abundant in metaquartzite?
Answer:Quartz.Question 26
What minerals commonly give schist a shiny foliated appearance?
Answer:Aligned platy mica minerals.Question 27
Which named metamorphic rock has slaty cleavage?
Answer:Slate.Question 28
Which named metamorphic rock commonly has visible schistosity?
Answer:Schist.Question 29
Which named metamorphic rock is made mainly of interlocking quartz crystals?
Answer:Metaquartzite.Question 30
A non-foliated rock fizzes with dilute acid. Which listed metamorphic rock is likely?
Answer:Marble, because it contains calcite.Question 31
A hard, non-foliated rock does not fizz and is mainly quartz. Which listed rock is likely?
Answer:Metaquartzite.Question 32
Why can marble and metaquartzite both lack foliation?
Answer:Their interlocking crystals need not be aligned, particularly when the parent rock consists largely of one mineral.Question 33
How can dilute hydrochloric acid help distinguish marble from metaquartzite?
Answer:Marble's calcite fizzes; quartz-rich metaquartzite normally does not.Question 34
How can a hand lens help identify schist?
Answer:It makes aligned mineral flakes and crystal size easier to see.Question 35
Why should an identification use both texture and mineralogy?
Answer:A single feature can occur in several rocks; combined evidence makes identification more reliable.Question 36
A fine rock splits into flat sheets but shows no visible large mica flakes. Suggest a name.
Answer:Slate, subject to checking its metamorphic context.Question 37
A rock has large glittering aligned flakes. Suggest a name.
Answer:Schist, if the diagnostic aligned flakes and other features are present.Question 38
A granite pluton cuts limestone. What metamorphic rock may occur next to it?
Answer:Marble, formed where heat recrystallises the limestone.Question 39
Sandstone beside a hot intrusion recrystallises. What named rock can form?
Answer:Metaquartzite.Question 40
A narrow altered zone follows both sides of a dyke. Which process is indicated?
Answer:Contact metamorphism caused by heat from the dyke.Question 41
Why does an aureole support the interpretation of an intrusion?
Answer:The magma heated pre-existing surrounding rock, so the altered zone records an igneous contact.Question 42
A wide mountain belt contains foliated schist. Which type of metamorphism is likely?
Answer:Regional metamorphism, associated with widespread pressure and heating.Question 43
What evidence distinguishes a baked margin from the igneous rock itself?
Answer:The baked margin is altered country rock outside the intrusion, rather than crystallised magma inside it.Question 44
An aureole follows a curved granite boundary on a map. What does it mark?
Answer:The zone where adjacent country rock was heated by the granite intrusion.Question 45
If an intrusion cuts schist, which formed first?
Answer:The schist formed before the magma intruded and cut it.Question 46
Can heat from a later intrusion alter an older metamorphic rock?
Answer:Yes. The older metamorphic rock can be affected by a later episode of contact metamorphism.Question 47
How can a parent rock influence the minerals in a metamorphic rock?
Answer:Its original chemical composition limits which minerals can form during recrystallisation.Question 48
Why should you describe both rocks when comparing marble and slate?
Answer:A comparison needs features of each: marble is non-foliated and calcite-rich; slate is fine and foliated.Question 49
What safety precaution is useful when examining a roadside rock cutting?
Answer:Use a safe authorised location away from traffic, wear suitable protective equipment and avoid unstable rock faces.Question 50
Which observations support a metamorphic identification in the field?
Answer:Crystal size and alignment, mineralogy, acid reaction where safe, and relationship to nearby structures or intrusions.
More Eduqas GCSE Geology topics
- 1.1 Minerals
- 1.2 Igneous Rocks and Processes
- 1.3 Sedimentary Rocks and their Fossil Content
- 1.4 Metamorphic Rocks and Processes
- 1.5 Deformational Structures
- 2.1 The Rock Cycle
- 2.2 Plate Tectonics
- 2.3 Geochronological Principles
- 2.4 Global Climate and Sea Level Change
- 2.5 The Origin and Development of Life on Earth
- 3.1 Planetary Geology
- 4.1 Earth Hazards and their Mitigation
- 4.2 Earth Resources and Engineering
Other Geology courses: Eduqas A-level Geology.
