Lecture 6

• Shoreline – is the line that marks the contact between land and sea. Each day, as tides rise and fall, the position of the shoreline migrates.
• Shore – refers specifically to the land along the edge of a body of water.
• Coast – refers to a larger geographical region that includes the shore as well as the adjacent land areas.
• Beach – an accumulation of sediment found along the landward margin of a water body
• White sand – due to skeletons or shells of foraminiferas (single-celled marine organisms), corals and other organisms.
• Black sand – result of eroded volcanic materials such as basalts (dark-colored volcanic rocks)
• Pink sand – originally white-colored sand beach turned pinkish ever since washed-up, red-colored corals spread all over the shore.
• Boulder beach – huge andesite boulders were produced by Mt. Iraya volcano and these boulders were broken down, polished and rounded by strong waves in Batanes.
• Shoreline – refers to the specific interface or line where land and water meet. It is dynamic.
• Coastline – is much broader boundary between land and water. It has features, including rocky cliffs, sandy beaches, or marshy shores.
• Wave-cut Cliff – also known simply as a cliff or a coastal cliff. It is a geological feature formed by the erosion of waves against a coastline.
• Notch – a narrow indention or cutout in the coastline. It is often formed through erosional processes such as wave action, weathering, or the movement of sediment
• Berm – refers to a nearly horizontal or gently sloping strip of land or sand found along the backshore of a beach.
• Foreshore – is a part of the shore exposed at low tide and submerged at high tide. It is the area where the ocean meets the land.
• Nearshore – extends from the shoreline to where waves break (surf zone) at the outer edge of the surf zone. It is the area where the water is shallow enough to be affected by wave action.
• Offshore – is the area beyond the nearshore zone. The water is deeper and further from the shore. It is associated with activities such as oil, drilling, fishing, and shipping.
• Swash refers to the movement of water rushing up the beach after a wave breaks, carrying sediment and debris landward.
• Backwash is the flow of water back down the beach after the swash.
• Beach drift – the uprush of water from each breaking wave (the swash) is at an oblique angle to the shoreline. However, the backwash is straight down the slope of the beach.
• Longshore Current – waves that approach the shore at an angle also produce currents within the surf zone that flow parallel to the shore and move substantially more sediment than beach drift
• Rip Currents – are concentrated movements of water that flow opposite the direction of breaking waves.
• Most of the backwash from spend waves finds its way back to the ocean as an unconfined flow across the ocean bottom called sheet flow
• Wave-cut Platform – a gently sloping, flat, or slightly inclined surface of rock that extends from the base of a wave-cut cliff out into the sea.
• Marine Terraces – relatively flat or gently sloping landforms that parallel the coastline and are typically found above present-day sea level.
• Sea Arch – is a natural rock arch formed by the erosive action of waves on coastal rock formations
• Sea Stack – a vertical column or pillar of rock that stands isolated from the coastline, often adjacent to cliffs or headlands
• Spit – is an elongated ridge of sand that projects from the land into the mouth of an adjacent bay. Often the end of a spit that is in the water hooks landward in response to the dominant direction of the longshore current.
• Bay – a body of water partially enclosed by land, usually with a wide mouth opening to the sea or another larger body of water, such as a lake or another bay
• Baymouth Bar – applied to a sandbar that completely crosses a bay, sealing it off from the open ocean.
• Tombolo – a ridge of sand that connects an island to the mainland or to another island, forms in much the same manner as a spit.
• Storm Surge – is a dome of water 65 to 80 kilometers wide that sweeps across the coast near the point where the eye makes the landfall.
• Hard Stabilization – are the structure built to protect a coast from erosion or to prevent the movement of sand along a beach.
• Jetties – structures typically built from a shoreline out into a body of water, often sea or a river, to direct currents and prevent sediment deposition. They’re also used for docking boats or ships
• Groins – are barriers built at a right angle to the beach to trap sand that is moving parallel to the shore. It is usually constructed of large rocks but may also be composed of wood
• Breakwaters – protect boats from the force of large breaking waves by creating a quiet water zone near the shoreline.
• Seawall – designed to armor the coast and defend property from the force of breaking waves. Seawalls cut this process short by reflecting the force of unspent waves seaward
• Beach Nourishment – involves adding large quantities of sand to the beach system. Extending beaches seaward makes buildings along the shoreline less vulnerable to destruction by storm waves and enhances recreational uses.
• Relocation – many coastal scientists and planners are calling for a policy shift from defending and rebuilding beaches and coastal property in high-hazard areas to relocating storm-damaged buildings in those places and letting nature reclaim the beach