Impermeable Layer

A layer of rock, sediment or soil that does not allow water to pass through. This could be caused by a lack of pore space or pore spaces that are so small that water molecules have difficulty passing through.

Related terms:

• layer depth effect
• surface boundary layer
• layer
• two-layer ocean
• mixed layer
• active layer
• planetary boundary layer
• E layer
• F1 layer
• Ekman layer