Oceanography - Chapter 10: Beaches, Shoreline Processes and the Coastal Ocean

Flashcards covering vocabulary terms related to beaches, shoreline processes, and the coastal ocean as discussed in the lecture.

Shore

Zone between lowest tide and highest land elevation affected by storm waves.

Coast

Extends inland from the shore as far as ocean-related features are found.

Coastline

Boundary between the shore and the coast.

Backshore

Part of the shore, landward of the high tide shoreline.

Foreshore

Part of the shore, exposed at low tide and submerged at high tide.

Shoreline

Migrates with the tide; the water's edge.

Nearshore

Extends seaward from the low tide line to the low tide breaker line.

Offshore

Beyond the low tide breakers.

Beach

Deposit of wave-worked sediment in the shore area.

Berm

Dry, gently sloping, elevated region of the beach composed of sediments.

Beach Face

Flat area exposed during low tide; also called the low tide terrace.

Longshore Trough

Low-lying area before longshore bars.

Wave Cut Bench

Flat area exposed by wave erosion.

Swash

Waves that rush up the beach face.

Backwash

Water that drains back to the ocean.

Longshore Current

Movement of water along the shore.

Longshore Transport

Movement of sediment parallel to the shoreline, caused by longshore current and wave action.

Erosional Shores

Shorelines with well-developed cliffs, often associated with tectonic uplift.

Depositional Shores

Shorelines gradually subsiding, with features like barrier islands and sand deposits.

Headlands

Protruding bits of land that absorb wave energy due to wave refraction.

Sea Stacks

Remnants of a headland after a sea arch collapses.

Marine Terrace

Flat-lying area, a former wave-cut bench uplifted by tectonic activity.

Barrier Islands

Long offshore sand deposits parallel to the coastline.

Bay Barrier

Sandbar that covers a bay.

Lagoon

Area of mixed freshwater and saltwater.

Spit

Barrier island that curves inward towards the mainland.

Tumbelo

Area only exposed during low tide.

Deltas

Deposits that form when rivers deposit sediment into the open ocean.

Distributaries

Branching channels carrying sediment to the ocean in a delta.

Beach Starvation

Occurs when rivers are dammed, blocking sediment supply to beaches.

Emerging Shoreline

Indicates shoreline risen above mean sea level.

Submerging Shorelines

Indicates shoreline at or below current sea level.

Eustatic Sea Level Changes

Sea level changes due to tectonic movements.

Isostatic Adjustments

Sea level changes due to local effects such as ice weight.

Hard Stabilization Features

Structures built to reduce coastal erosion.

Groins

Piles of rocks perpendicular to the coastline that trap sand.

Jetties

Two groins parallel to each other, often blocking an inlet.

Breakwaters

Structures parallel to the shoreline to protect from wave activity.

Sea Walls

Walls built to protect homes and businesses from wave action.

Beach Replenishment

Adding sand to beaches to combat erosion.

Relocation

Moving buildings away from the coastline to save them.

Coastal Waters

Waters close to continental margins; shallow waters off beaches.

Halocline

Layer where there is a drastic change in salinity.

Isothermal

Same temperature in water column.

Geostrophic Currents

Currents in coastal waters influenced by Coriolis effect and gravity.

Davidson Current

Current that flows northward off the coast of Washington and Oregon.

Estuaries

Area where fresh water mixes with salty ocean water.

Coastal Plain Estuary

Estuary caused by a drowned river valley.

Fjord Estuary

Estuary caused by sea level rise flooding glacial valleys.

Bar Built Estuary

Estuary with barrier islands, lagoons, sandbars.

Tectonic Estuary

Estuary due to faulting and folding of rocks.

Harmful Algal Blooms

Algal bloom caused due to sewage and fertilizers being introduced into the water.

Lagoons

Shallow bodies of brackish water landward of barrier islands.

Wetlands

Ecosystems where water table is close to the surface and ground is saturated.

Salt Marshes

Marshes that support salt grasses and other halophytic plants.

Mangrove Swamps

Swamps with salt-tolerant mangrove trees.