Suites of landforms within glacial landscapes — Eduqas A-Level Geography

Glacial landscapes are not random collections of features; they are organised into distinct suites of landforms that reflect the processes and history of glaciation. A 'suite' refers to a group of landforms that are genetically related, meaning they form together under the same glacial conditions. Understanding these suites helps geographers reconstruct past ice sheet dynamics, climate change, and landscape evolution. For example, the 'alpine glacial suite' includes arêtes, pyramidal peaks, cirques, and U-shaped valleys, all formed by the same erosional processes in mountainous regions.

In WJEC A-Level Geography, you will study two main suites: the erosional suite of upland glaciated areas and the depositional suite of lowland glaciated areas. The erosional suite features landforms like cirques, arêtes, and troughs, shaped by glacial erosion (plucking and abrasion). The depositional suite includes drumlins, moraines, and outwash plains, formed by glacial and fluvial deposition. These suites are not isolated; they often overlap in space and time, especially at glacier margins. Recognising these associations allows you to explain how landscapes evolve from glacial to post-glacial conditions.

This topic is crucial because it links geomorphological processes to landscape patterns, a key skill in physical geography. It also connects to climate change, as relict glacial landscapes provide evidence of past ice ages. In exams, you may be asked to describe and explain the formation of a named suite, or to compare suites from different glacial environments. Mastering this topic will help you analyse OS maps, field sketches, and satellite images with confidence.

• →Glacial erosion processes: plucking (freeze-thaw action removing rock fragments) and abrasion (rock fragments embedded in ice scraping the bedrock).
• →Erosional landform suite: cirques (armchair-shaped hollows with a steep backwall and rock lip), arêtes (sharp ridges between two cirques), pyramidal peaks (e.g., the Matterhorn), and U-shaped glacial troughs with truncated spurs and hanging valleys.
• →Depositional landform suite: drumlins (elongated, streamlined hills indicating ice flow direction), terminal moraines (ridges of till marking the glacier's maximum extent), and outwash plains (braided river deposits of sorted sand and gravel beyond the glacier).
• →Glacial till: unsorted, unstratified sediment deposited directly by ice (lodgement till) or from melting ice (ablation till).
• →Glaciofluvial processes: meltwater streams sorting and depositing sediment, forming eskers (sinuous ridges of sand and gravel) and kames (mounds of stratified drift).

• Variations in glacial landscapes between highland and lowland
• Variations in glacial landscapes between ice sheets and valley glaciers

• 💡When describing landform formation, always mention the specific processes (plucking, abrasion, freeze-thaw) and the role of meltwater. Avoid vague terms like 'ice carved it out'.
• 💡Use annotated diagrams in your answers. For example, sketch a cirque and label the backwall, rock lip, and rotational slip. This shows the examiner you understand the spatial relationships within a suite.
• 💡Link landforms to past climate conditions. For instance, terminal moraines indicate a stillstand or readvance during deglaciation. This demonstrates higher-level understanding of glacial chronology.

• Misconception: All glacial landforms are formed by ice alone. Correction: Many features, especially in the depositional suite, are formed by meltwater (glaciofluvial processes). For example, outwash plains and eskers are water-laid, not ice-laid.
• Misconception: U-shaped valleys are formed by rivers. Correction: U-shaped valleys are carved by glacial ice, which erodes the valley floor and sides, creating a wide, flat-bottomed shape. River valleys are V-shaped.
• Misconception: Drumlins indicate the direction of ice flow from their steep end. Correction: The steeper, blunt end (stoss) faces the direction from which the ice came; the tapered end (lee) points in the direction of ice flow.