18-Geol-A1 Mineralogy and Petrology
Worked solutions to 8 past sittings (2013–2019), 90 questions. Pick a sitting, or start from a topic below.
Topics across the sittings
Topics that come up in more than one sitting, taken from the headings of our worked solutions. A topic counts once per sitting.
- Evidence for Crystal Fractionation (6 sittings): December 2019 Q3 · December 2018 Q3 · December 2017 Q3 · May 2017 Q3 · December 2016 Q4 · Undated paper Q3
- Metasomatism (6 sittings): December 2019 Q9 · December 2018 Q8 · December 2017 Q8 · May 2017 Q8 · December 2016 Q10 · May 2016 Q9
- Crustal Assimilation (5 sittings): December 2019 Q3 · December 2018 Q3 · December 2017 Q3 · May 2017 Q3 · December 2016 Q4
- Formation (5 sittings): December 2018 Q7 · December 2017 Q6 · May 2017 Q6 · December 2016 Q7 · May 2016 Q7
- Metamorphism (5 sittings): December 2019 Q9 · December 2017 Q8 · May 2017 Q8 · December 2016 Q10 · May 2016 Q9
- Pyroxene (5 sittings): December 2018 Q1 · May 2017 Q1 · December 2016 Q1 · May 2016 Q1 · Undated paper Q1
- Amphibole (4 sittings): December 2018 Q1 · May 2017 Q1 · December 2016 Q1 · May 2016 Q1
- Bowen's Reaction Series (4 sittings): December 2019 Q11 · December 2018 Q11 · December 2017 Q11 · Undated paper Q11
- Endoskarn (4 sittings): December 2017 Q8 · May 2017 Q8 · December 2016 Q10 · May 2016 Q9
- Exoskarn (4 sittings): December 2017 Q8 · May 2017 Q8 · December 2016 Q10 · May 2016 Q9
- Four Basic Agents of Metamorphism (4 sittings): December 2017 Q4 · May 2017 Q4 · December 2016 Q5 · May 2016 Q5
- Hornfels (4 sittings): December 2017 Q8 · May 2017 Q8 · December 2016 Q10 · May 2016 Q9
- Ignimbrites (4 sittings): December 2019 Q6 · December 2018 Q7 · May 2017 Q6 · May 2016 Q7
- Magma Mixing (4 sittings): December 2018 Q3 · December 2017 Q3 · May 2017 Q3 · December 2016 Q4
- Silicate Group Differences (4 sittings): December 2019 Q1 · December 2017 Q1 · May 2017 Q1 · Undated paper Q1
Questions by sitting
December 2019
- Question 1: Feldspar and Olivine — Silicate Group Differences
- Question 2: Element Substitution in Mineral Structures — Goldschmidt's Rules
- Question 3: Evidence for Crystal Fractionation, Liquid Immiscibility and Crustal Assimilation
- Question 4: Two of the Seven Crystal Systems — Hexagonal and Triclinic
- Question 5: Dynamic Metamorphism
- Question 6: Ignimbrites — Formation by Eruption-Column Collapse
- Question 7: MORB — Formation by Decompression Melting
- Question 8: The Wilson Cycle — Ocean Basin Opening and Closing
- Question 9: Metamorphism vs. Metasomatism
- Question 10: Four Common Igneous Minerals in a Felsic Rock — Hand-Lens/Microscope Diagnostics
- Question 11: Bowen's Reaction Series and the Origin of Igneous Rock Diversity
- Question 12: Sulfide Minerals — Formula and Diagnostic Properties
December 2018
- Question 1: Amphibole and Pyroxene — Crystallographic Differences
- Question 2: Oxide Ore Minerals — Fe, Cr, Ti, U, Cu
- Question 3: Evidence for Crystal Fractionation, Magma Mixing and Crustal Assimilation
- Question 4: The Seven Crystal Systems
- Question 5: Dynamic Metamorphism
- Question 6: Lava Flow Morphology — Sensitivity to Composition, Temperature, Viscosity and Vent Proximity
- Question 7: Ignimbrites — Formation
- Question 8: Metasomatism and Skarn Formation
- Question 9: What Causes Melting in Different Tectonic Settings
- Question 10: Effusive vs. Explosive Eruptions
- Question 11: Bowen's Reaction Series and the Origin of Igneous Rock Diversity
- Question 12: Carbonate Minerals
December 2017
- Question 1: Garnet and Feldspar — Silicate Group Differences
- Question 2: Sulfide Ore Minerals — Zn, Cu, Ni, Fe, Pb
- Question 3: Evidence for Crystal Fractionation, Magma Mixing and Crustal Assimilation
- Question 4: Four Basic Agents of Metamorphism
- Question 5: Contact Metamorphism
- Question 6: A'a vs. Pahoehoe Lava — Formation and What They Reveal
- Question 7: Ophiolites — Formation and Preservation in the Geological Record
- Question 8: Metamorphism vs. Metasomatism — Exoskarn, Endoskarn and Hornfels
- Question 9: What Causes Melting in Different Tectonic Settings
- Question 10: Effusive vs. Explosive Eruptions
- Question 11: Cumulate Processes and Ultramafic Rocks — Bowen's Reaction Series
- Question 12: Carbonate Minerals
May 2017
- Question 1: Olivine, Amphibole and Pyroxene — Silicate Group Differences
- Question 2: Mineral Examples for Mg, Fe, Ca, Na, K and Al
- Question 3: Evidence for Crystal Fractionation, Magma Mixing and Crustal Assimilation
- Question 4: Four Basic Agents of Metamorphism
- Question 5: Regional Metamorphism
- Question 6: Ignimbrites — Formation and Internal Stratigraphy
- Question 7: Komatiites — Formation and Absence of Modern Analogues
- Question 8: Metamorphism vs. Metasomatism — Exoskarn, Endoskarn and Hornfels
- Question 9: Melting Mechanisms by Tectonic Setting
- Question 10: Effusive vs. Explosive Eruptions
- Question 11: Calc-Alkaline vs. Tholeiitic and Alkaline Rock Series — AFM Diagram
- Question 12: Three Controlling Factors on Magma Viscosity
- Question 13: Three Types of Igneous Layering
December 2016
- Question 1: Mica, Amphibole and Pyroxene — Structural Differences
- Question 2: Oxide Ore Minerals — Sn, Fe, Al, Ti, U
- Question 3: Sanidine, Microcline and Orthoclase — K-Feldspar Polymorphs
- Question 4: Evidence for Crystal Fractionation, Magma Mixing and Crustal Assimilation
- Question 5: Four Basic Agents of Metamorphism
- Question 6: Contact Metamorphism
- Question 7: Ophiolites — Formation and Internal Stratigraphy
- Question 8: Barrovian vs. Buchan Facies Series — Pelitic Mineralogy
- Question 9: Paired Metamorphic Belts
- Question 10: Metamorphism vs. Metasomatism — Exoskarn, Endoskarn and Hornfels
- Question 11: Partial Melting Mechanisms by Tectonic Setting
- Question 12: Volcanic Eruption Types
- Question 13: Calc-Alkaline vs. Tholeiitic and Alkaline Rock Series — AFM Diagram
May 2016
- Question 1: Mica, Amphibole and Pyroxene — Crystallographic Differences
- Question 2: Sulphide Ore Minerals — Sn, Zn, Ni, Pb, Cu
- Question 3: Magmatic Differentiation
- Question 4: Cumulate Processes — Categories by Intercumulus Liquid
- Question 5: Four Basic Agents of Metamorphism
- Question 6: Contact Metamorphism
- Question 7: Ignimbrites — Formation and Internal Stratigraphy
- Question 8: Metamorphic Reaction Mechanisms
- Question 9: Metamorphism vs. Metasomatism — Exoskarn, Endoskarn and Hornfels
- Question 10: Oceanic Crust — Cross Section, Age Contrast and Subduction
- Question 11: Metamorphic Index Mineral, Facies and Facies Series
- Question 12: AFM Diagrams — Barrovian Index Mineral Progression
- Question 13: Volcanic Eruption Types
December 2013
- Question 1: Mineralogy and Petrology Short-Answer Set
- Question 2: Mineral Identification and the Diopside–Anorthite Phase Diagram
- Question 3: Earth Structure, Optical Mineralogy, Igneous and Metamorphic Processes
Undated paper
- Question 1: Olivine and Pyroxene — Silicate Group Differences and a Shared Host Rock
- Question 2: Solid Solution and Exsolution in Mineralogy
- Question 3: Evidence for Crystal Fractionation, Immiscibility and Crustal Contamination
- Question 4: Two of the Seven Crystal Systems — Hexagonal and Triclinic
- Question 5: Thermal (Contact) Metamorphism
- Question 6: Ophiolites — Obducted Oceanic Lithosphere
- Question 7: LIPs — Large Igneous Provinces
- Question 8: The Wilson Cycle — Ocean Basin Opening and Closing
- Question 9: What Causes Melting in Different Tectonic Settings
- Question 10: Anatexis — Crustal Partial Melting
- Question 11: Bowen's Reaction Series and the Origin of Igneous Rock Diversity
- Question 12: Oxide Minerals — Magnetite and Hematite