4.3 A Flashcards
What is concordant and discordant rock
Concordant rocks are beds of different layered rock while disconcordant rock alternates.
How does discordant rock influence costal erosion
Discordant rock allows for formations such as headlands and bays. Headlands are usually formed with harder rock and bays that have softer rock
What are joints and faults and how do they influence landforms
A joint is a fracture along a rock bed but no movement has influenced it while a fault is a fracture or even a break in the rock due ro applied pressure. Joints usually are in sets and are parallel to each other . They are easily identifiable in landforms as you can see huge cracks .
How are caves formed
When rain picks up carbon dioxide and soils into a surface it can eventually turn into a weak acid , in this case the acid will dissolve nearby limestone creating fractures in rocks and may even widen holes big enough to be caves.
How are arches formed
If a cave is formed in a headland and eventually collapses due to hydraulic action and erosion it will become an arch joining 2 pieces of land together similar to an arch.
What are cliffs and how do they impact the landscape
Cliffs are formed by rocks that are resistant to the erosion and weathering . Sedimentary rocks that are most likely to be responsible are chalk , limestone , and dolomite . Creating a slanted face called the rock face disrupting erosion .
What is a wave cut platform
Wave cut platforms are formed when the base of a cliff is attacked by waves and eventually though hydraulic action the top of the cliff will snap off. The backwash will bring the sediment back towards the cliff and create a wave cut platform.
How are stacks formed
When a cave collapses an arch is formed however when the water erodes the rock from the arch it will once again collapse leaving the rocks hitting the water called stacks
How are bars formed
Bars are spits that eventually grow out and connect to other lands do to this the water behind them is segregated off creating a lagoon which eventually dries up creating a salty marsh
How are spits formed
A spit is an extended body of beach material. When the prevailing winds cause longshore drift sediment is pushed up and down and on occasion spits can be created.
