Core Unit 1: Patterns and Processes in the Physical Environment
Core Unit 1 treats the physical environment as a set of interacting systems: plate tectonics and the rock cycle supply the material, while weathering, erosion, transport and deposition sculpture the landforms. The exam tests whether you can explain a process accurately and attach it to a named landform in a named place.
Rules that decide marks
- Every physical answer is a chain: cause → process → landform → named example.
- Rock structure constrains landform. Karst needs soluble, jointed limestone; granite gives tors and acidic soils; basalt gives plateau surfaces.
- Tectonics: divergent boundaries (Mid-Atlantic Ridge) create new crust; convergent boundaries with subduction (the Andes) fold and melt it; transform boundaries (San Andreas) slide.
- Weathering happens in situ; erosion involves removal and transport. Carbonation, hydrolysis and freeze–thaw are the most frequently examined weathering processes.
- Isostasy explains why uplands are being slowly uplifted as denudation removes mass.
Worked example
Explain the formation of a limestone pavement. Reasoning: Carboniferous limestone is bedded and jointed (structure) → rainwater absorbs CO₂ and forms weak carbonic acid → carbonation dissolves calcium carbonate along the joints, widening them into grikes → the residual blocks between are clints → the Burren, Co. Clare. The mark-earning phrase is "solution along joints", not "rain wears the rock away".
Traps that cost marks
- Describing a landform but skipping the process, or naming a process but never naming a place.
- Mixing compression (folding) with tension (normal faulting).
- Calling soil creep "weathering" when it is mass movement.
- Giving a world example when the question asks for an Irish one.