Abrasion: When rocks grind along a rock platform like sandpaper. Over time the rock becomes smooth.
Arch: The wave-eroded rock bridge that spans a passage through a headland.
Backwash: Gravity causes a wave to move down a beach and return to the sea.
Bay: An inlet of the sea where the land curves inward, usually with a beach.
Beach: A sloping area of sand or pebbles between the low and high-tide water marks.
- The boundary between the land and sea.
Beach Replenishment: Adding sand and shingle to widen or improve a beach.
Bedding plane: The surface between 2 layers (or strata) in sedimentary rocks.
Carboniferous Limestone: A sedimentary rock made from deposits that were formed between 363 and 325 million years ago, consisting mainly of CaCO₃.
Caves: A hollow at the base of a cliff that has been eroded by waves backwards.
Chalk: A soft, white, powdery limestone consisting chiefly of foraminifers.
Clay: Clay soil formed by sedimentary deposits.
Cliffs: A mass of rock that rises very high and is almost vertical, like a wall.
Concordant Coast: Has the same type of rock along its coastline and the same rate of erosion. The strata are parallel to the coast.
Constructive Wave: Gently breaking waves with a stronger swash than backwash, adding more material to the beach than it removes.
Deposition: A process where sediments are dropped by the river, glacier, or waves that carried them.
Destructive Wave: A strong wave that removes material from a coastline.
Dip Slope: Land that follows the same gentle slope as the layers of rock underneath.
Discordant Coast: Coastlines where the geology alternates between strata (bands) of hard and soft rock so the strata are at perpendicular angles to the coast.
Faults: A fracture or zone of fractures between 2 blocks of rock caused by past tectonic movement.
Erosion: Coastal erosion is the wearing away and breaking up of rock along the coast.
Fetch: The length of water over which the wind has blown, affecting the size and strength of the waves.
Freeze-thaw Weathering: Occurs when rocks are porous (contain holes) or permeable. Water enters cracks in the rock. When temperatures drop, the water freezes and expands, causing the crack to widen. The ice melts and makes its way deeper into the cracks.
Geological Structure: Usually the result of the powerful tectonic forces that occur within the Earth. These forces fold and break rocks and form deep faults.
Glacial: A period of time with lower average temperatures, causing widespread glaciations.
Granite: A coarse-grained igneous rock composed chiefly of orthoclase, albite feldspars, and quartz.
Groyne: An active structure extending from the shore into the sea, most often perpendicular to the shoreline.
Hard Rock: A hard rock type is more resistant to erosion.
Headland: An area of more resistant rock jutting out into the sea from the cliff line.
Igneous: Formed through the cooling and solidification of magma or lava.
Impermeable: Not permitting the passage of a fluid through the pores, e.g., impermeable rock such as clay.
Interglacial: A period of time between two glaciations with higher average temperatures.
Joints: Small, usually vertical cracks found in many rocks.
Longshore Drift: The movement of material along a beach transported by wave action in a zigzag movement.
Lowland: Flat areas not very high above sea level.
Metamorphic: Rock that has undergone transformation by heat and/or pressure.
Permeable: Rocks that allow water to pass through them—chalk.
Plucking: A process of erosion occurring during glaciation. As ice and glaciers move, they scrape along the surrounding rock and pull away pieces of it, causing erosion.
Prevailing Wind: The most common wind direction in a certain area.
Rockfall: A form of mass movement where fragments of rock fall freely from a cliff face.
Scree: Angular rock pieces created from freeze-thaw weathering.
Sedimentary: Rock formed of small particles that have been eroded, transported, and deposited in layers, such as sandstone, or from remains of plants and animals.
Soft Rock: A rock type not resistant to erosion.
Spit: An extended stretch of sand/shingle jutting out into the sea from the land. Spits occur when there's a change in the shape of the landscape or there's a river mouth.
Stack: When an arch collapses, it leaves a headland on one side and a stack on the other.
Strata: Distinct layers of rock.
Stump: A short piece of rock found at the end of a headland after a stack has collapsed.
Till: Sediment deposited by melting glaciers or ice sheets.
Upland: Often mountainous and high above sea level.
Wave-cut Notch: A small overhang at the base of the cliff formed where the wave action is greatest.
Wave-cut Platform: The flat, rocky area left behind when waves erode a cliff away, often seen at low tide.
Weathering: The breakdown and decay of rock by natural processes acting on rocks, cliffs, and valley sides.