Which mechanism primarily contributes to the U-shaped profile of a fjord?

💡 Explanation

When a glacier occupies a valley, glacial abrasion and bedrock plucking occur due to the immense pressure and the freeze-thaw cycle, eroding the valley walls and floor, deepening and widening the valley to form a U shape. Therefore glacial erosion creates this shape, rather than chemical weathering, river action, or tectonic forces resulting in a V shape.

• Which mechanism causes reduced vertical nutrient circulation within stratified ocean regions?
• Which risk increases when construction on an alluvial fan restricts sediment flow from upstream?
• Which outcome arises when tectonic uplift decreases a lake's catchment area and inflow?
• Which outcome results when thaw cycles in permafrost increase rate of solifluction?
• Which glacial process creates tarns within cirques after glacial retreat?
• Which risk increases when a major oceanic gyre's rotational speed slows down significantly?