The Earth's Surface and Processes
What this domain tests
JC Geography examines how internal and external processes shape the Earth's surface. You must link process to landform, use correct sequence words, and apply rock-cycle vocabulary accurately.
Core rules and concepts
- The Earth has a crust, mantle, outer core and inner core. The lithosphere is broken into tectonic plates that move over the asthenosphere.
- At divergent (constructive) boundaries, plates move apart; magma rises, forming mid-ocean ridges and rift valleys. At convergent (destructive) boundaries, denser oceanic crust subducts, producing trenches, volcanic arcs and fold mountains. At transform (conservative) boundaries, plates slide past each other, causing earthquakes.
- The rock cycle links igneous, sedimentary and metamorphic rocks through melting, cooling, weathering, erosion, deposition, compaction and metamorphism.
- Weathering breaks rock in situ; erosion removes and transports material; deposition lays it down. Physical weathering includes freeze-thaw; chemical includes carbonation; biological includes root action.
- Fluvial processes produce V-shaped valleys, waterfalls, meanders and floodplains. Coastal processes produce cliffs, wave-cut platforms, spits and tombolos.
Worked example
Explain the formation of a waterfall. (1) A band of resistant rock lies over softer rock. (2) The softer rock erodes faster, creating a step. (3) Hydraulic action and abrasion undercut the resistant cap, forming a plunge pool. (4) The unsupported cap collapses; the waterfall retreats upstream, leaving a gorge. Reasoning: marks come from naming processes, not just saying 'water wears away rock'.
Traps that cost marks
- Describing weathering as 'rock being moved'-that is erosion.
- Giving a landform sequence out of order (collapse before undercutting).
- Forgetting to name the plate boundary type when explaining earthquakes or volcanoes.