Cameroon GCE advanced level June 2025 geology 1

Here are the extracted questions from the provided images:

Page 1

1. An interstellar cloud of dust, hydrogen, helium and other ionized gases is called:

   A Comet

   B Galaxy

   C Nebula

   D Meteor

2. The closest galaxy to the planet Earth is:

   A Milky Way galaxy

   B Andromeda galaxy

   C Elliptical galaxy

   D Irregular galaxy

3. What name is given to the layer of the Earth between 95km and 2900km?

   A Mantle

   B Lower mantle

   C Upper Mantle

   D Outer core

4. Determine the average velocity of wave Y at the surface of the Earth:

   A 0km/s

   B 8km/s

   C 12km/s

   D 14km/s

5. The deepest depth attained by wave X is approximately:

   A 1900km

   B 2900 km

   C 3900 km

   D 3900 km

6. Seismic waves that cause the components of a rock to vibrate perpendicularly to the direction of wave propagation are called:

   A Shear waves

   B Compressional waves

   C Love waves

   D Rayleigh waves

7. How many diagonal planes of symmetry does this crystal have?

   A 3 planes

   B 7 planes

   C 5 planes

   D 4 planes

8. An example of a mineral with such a habit is:

   A Rutile

   B Idocrase

   C Apatite

   D Zircon

9. A crystal face has as parameters 2a, b, 1c. What is the Miller Index of this face?

   A 201

   B 102

   C 102

   D 202

10. Which physical property of a given mineral displays the greatest variation?

    A Colour

    B Hardness

    C Lustre

    D Streak

Page 2

11. Identify the silicate mineral:

    A Biotite

    B Olivine

    C Hornblende

    D Pyroxene

12. The silicate mineral in question 11 above has a:

    A Sheet structure

    B Single chain structure

    C Isolated structure

    D Double chain structure

13. Identify the mineral represented by the letter X.

    A Triclinic pyroxene

    B Hypersthene

    C Hornblende

    D Augite

14. An example of a mineral in the continuous series which is an essential mineral in gabbro is:

    A Labradorite

    B Oligoclase

    C Andesine

    D Anorthite

15. In which of the following layers is basaltic magma most likely to originate?

    A Lower crust

    B Upper mantle

    C Upper crust

    D Lower mantle

16. If this rock is phaneritic, it is most likely to be:

    A Diorite

    B Gabbro

    C Granite

    D Peridotite

17. The essential minerals of the rock mentioned in 16 above will be:

    A Quartz, micas, plagioclase

    B Andesine and hornblende

    C Augite and labradorite

    D Quartz, micas, feldspars and amphiboles

18. Identify the texture shown on the diagram above:

    A Graphic

    B Ophitic

    C Porphyritic

    D Poikilitic

19. The texture mentioned in question 18 was most likely formed as a result of:

    A Simultaneous crystallisation of minerals

    B Crystallisation in the plutonic and volcanic environments

    C Very slow crystallisation of magma

    D Crystallisation in an environment where crystals grow at different rates