Physical Geology and Geomorphology
Physical Geology and Geomorphology tests how Earth's internal and surface processes produce landscapes, with Karnataka examples. Expect questions on Earth's layered structure, plate boundaries, weathering, mass wasting, and fluvial, coastal, karst and glacial landforms.
Core rules
- Earth is compositionally layered into crust, mantle and core; the lithosphere is the rigid outer shell that breaks into plates.
- Endogenic processes (tectonism, volcanism) build relief; exogenic processes (weathering, erosion, deposition) reduce it.
- Weathering breaks rock in place; erosion removes and transports the debris.
- Running water erodes by hydraulic action, abrasion and solution, and deposits where gradient and velocity fall.
- Karnataka has three physiographic divisions: the coastal Karavali plain, the Western Ghats (Malnad) and the Deccan Plateau (Bayaluseeme).
Worked example
A river flows from the Western Ghats onto the coastal plain. Explain why a waterfall occurs near the Ghat edge and a floodplain develops near the coast. Reasoning: the Ghat edge has a steep gradient and resistant rock, so vertical erosion dominates and creates a knickpoint, as at Jog Falls on the Sharavathi. Downstream, the gradient flattens, velocity falls, and the river deposits silt to form a floodplain and meanders.
Traps
- Do not treat weathering and erosion as synonyms; weathering produces regolith, erosion transports it.
- A waterfall indicates a break in slope or resistant bed, not simply "fast water".
- In Karnataka, the Western Ghats are a escarpment, not a plate boundary.
Exam focus
Link each landform to a process and a Karnataka location.