Rocks - Practice Test 5

Attempt the quiz above first, then review every question with its correct answer and a short explanation below.

1. Q1.The Palisades Sill in New York is an example of:

   • A.Intrusive Igneous rock formation✓ Correct Answer
   • B.Sedimentary layer
   • C.Metamorphic zone
   • D.Volcano

   Explanation: A sill is a horizontal intrusion.

2. Q2.Kimberlite rocks are famous for containing:

   • A.Diamonds✓ Correct Answer
   • B.Gold
   • C.Oil
   • D.Coal

   Explanation: Kimberlite pipes are the primary source of diamonds.

3. Q3.Lapis Lazuli is a:

   • A.Metamorphic rock✓ Correct Answer
   • B.Igneous rock
   • C.Sedimentary rock
   • D.Mineral only

   Explanation: It is a rock (aggregate of minerals like lazurite), technically metamorphic.

4. Q4.Which rock is used in making statues?

   • A.Marble✓ Correct Answer
   • B.Shale
   • C.Coal
   • D.Pumice

   Explanation: Marble is preferred for sculpture due to its softness and beauty.

5. Q5.Gneiss is distinguished by:

   • A.Alternating bands of light and dark minerals✓ Correct Answer
   • B.Solid black color
   • C.High porosity
   • D.Softness

   Explanation: Gneissic banding is its defining feature.

6. Q6.Which of these is a discordant intrusive igneous body?

   • A.Dyke✓ Correct Answer
   • B.Sill
   • C.Lava flow
   • D.Laccolith (usually concordant)

   Explanation: Dykes cut across existing rock layers vertically.

7. Q7.A massive intrusive rock body is called:

   • A.Batholith✓ Correct Answer
   • B.Dyke
   • C.Sill
   • D.Vein

   Explanation: Batholiths are huge magma chambers that cooled underground.

8. Q8.Sandstone is formed from grains of:

   • A.Sand (Quartz)✓ Correct Answer
   • B.Clay
   • C.Lime
   • D.Gravel

   Explanation: Sandstone is cemented sand grains.

9. Q9.Shale is formed from:

   • A.Clay and Silt✓ Correct Answer
   • B.Sand
   • C.Gravel
   • D.Volcanic Ash

   Explanation: Shale forms from compacted mud/clay.

10. Q10.The transformation of rocks takes place due to:

    • A.Heat, Pressure, and Chemical action✓ Correct Answer
    • B.Wind only
    • C.Water only
    • D.Moonlight

    Explanation: These are the agents of metamorphism.

11. Q11.Contact metamorphism occurs due to:

    • A.Heat from magma✓ Correct Answer
    • B.Pressure from mountains
    • C.Water erosion
    • D.Wind

    Explanation: Existing rocks get cooked by touching hot magma.

12. Q12.Regional metamorphism occurs due to:

    • A.Pressure and Heat over large areas (Tectonics)✓ Correct Answer
    • B.Lava flow
    • C.Weathering
    • D.Meteor impact

    Explanation: Mountain building creates pressure over wide regions.

13. Q13.Which rock is used for making glass?

    • A.Sandstone (Quartz sand)✓ Correct Answer
    • B.Limestone
    • C.Granite
    • D.Basalt

    Explanation: Silica sand is the main ingredient.

14. Q14.Which rock is used as a writing tool (chalk)?

    • A.Chalk (Limestone)✓ Correct Answer
    • B.Slate
    • C.Coal
    • D.Sandstone

    Explanation: Natural chalk is a soft limestone.

15. Q15.The Giant's Causeway in Ireland is made of:

    • A.Basalt columns✓ Correct Answer
    • B.Granite boulders
    • C.Limestone pillars
    • D.Sandstone

    Explanation: It features hexagonal basalt columns from cooling lava.

16. Q16.Tuff is a rock made from:

    • A.Volcanic Ash✓ Correct Answer
    • B.Sand
    • C.Clay
    • D.Gravel

    Explanation: Tuff is consolidated volcanic ash.

17. Q17.Which element is common in both Felsic and Mafic rocks?

    • A.Silica✓ Correct Answer
    • B.Magnesium
    • C.Iron
    • D.Potassium

    Explanation: All igneous rocks are silicate based (just different amounts).

18. Q18.Andesite is named after:

    • A.Andes Mountains✓ Correct Answer
    • B.Andy
    • C.An island
    • D.A planet

    Explanation: Common in the Andes volcanic arc.

19. Q19.The property of a mineral to break along flat surfaces is:

    • A.Cleavage✓ Correct Answer
    • B.Fracture
    • C.Hardness
    • D.Luster

    Explanation: Cleavage is breakage along planes of weakness.

20. Q20.Mohs Scale measures:

    • A.Mineral Hardness✓ Correct Answer
    • B.Rock Weight
    • C.Earthquake Intensity
    • D.Temperature

    Explanation: It ranks minerals from softest (1) to hardest (10).