Advanced level 2025 North West regional mock geology guide
Advanced level 2025 North West regional mock geology guide
MARK SCHEME REGIONAL MOCK 2025 0755 A/L GEOLOGY
PAPER ONE
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| C | B | B | D | A | B | A | C | D | C |
| 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 |
| D | B | C | D | B | A | C | A | D | C |
| 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 |
| B | A | C | A | C | B | C | B | C | B |
| 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 |
| A | D | B | C | A | B | D | A | C | B |
| 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 |
| C | B | D | B | A | B | B | C | C | D |
PAPER TWO GUIDE
| 1.(a) | Definition of the following: |
| i. Meteoroids: Pieces of rocks found between the planets and the asteroid OR small rocky or metallic bodies in outer space, typically ranging in size from tiny grains to objects about a meter in diameter OR small celestial objects found in space generally |
|
| smaller than asteroids, with sizes that can vary from tiny dust particles to objects up to a meter in diameter | Any one correct |
| definition = 2 marks ii.Chondrites: Stony meteorites composed primarily of small round particles called chondrules. |
1 ½ marks |
iii.Planets: Large bodies that revolve around the sun (star) and are incapable of generating light internally OR non – luminous
celestial bodies illuminated by light from the sun around which they revolve OR celestial bodies that orbit a star are spherical and
| have cleared their orbits of other debris. (b) Short notes on the following: |
Any one correct definition = 1 ½ marks |
i. Asthenosphere:
➢ A semi fluid or semi molten or plastic layer of the Earth’s upper mantle
➢ It is situated beneath the lithosphere and extends from about 100km to 200km in depth
➢ The asthenosphere is characterized by diminished seismic wave velocities and rocks that are close to melting
➢ The materials in this layer include silicate minerals that are partially molten
➢ It is ductile and can flow slowly making it capable to deform under stress
| ➢ It acts as a lubricating layer for the lithosphere enabling tectonic plates to move. ii. Shadow zone: |
Any 3 points for 1 mark each |
➢ A region or area of the Earth’s interior where seismic waves (P and S) from an earthquake are not detected by
seismographs.
➢ This zone exists between 1030 and 1430 or 1050 and 1420 from the earthquake epicentre.
➢ In this zone, P waves are refracted while S waves are completely blocked.
➢ The existence of the shadow zone for S waves indicates that the outer core is liquid as S waves do not travel through
liquids. Any 3 points for 1 mark each
iii.Discontinuity:
➢ A boundary or layer within the Earth separating different layers by virtue of change in composition or physical state of
material OR a surface marking a change in physical state and /or chemical composition within the Earth OR a boundary
between different layers of the Earth’s interior where there is a significant change in physical or chemical properties OR a
boundary or transition zone between different layers of the earth’s interior characterized by changes in composition,
density and physical properties. Any one correct definition= 1 mark
➢ Types of discontinuity;
– Conrad: separating SIAL (upper crust) from SIMA (lower crust)
