Table of Contents
- 1 What is a soft cliff?
- 2 What is cliff morphology?
- 3 What is a complex cliff profile?
- 4 Is sandstone a hard or soft rock?
- 5 What are cliff features?
- 6 What are micro features of a cliff?
- 7 What rocks are hard and soft?
- 8 What are the soft rocks?
- 9 How are steep cliffs formed and how are they formed?
- 10 Which is erosional landforms have a lower cliff profile?
What is a soft cliff?
Soft cliffs are formed of relatively easily eroded rocks such as clays, friable sands, and glacial deposits, contrasting with much more resistant ‘hard’ rocks.
What is cliff morphology?
A common coastal cliff morphology is the slope-over-wall profile: a rounded weathered top and a vertical wall below. In many cases cliffs are fronted by shore platforms, which can be tens to many hundreds (or even thousands) of meters wide.
What is a complex cliff profile?
Complex cliff profiles are produced where cliffs are composed of strata of differing lithology. Resistant strata erode and weather slowly, retreating less rapidly. They may form a ‘bench’ feature at the cliff base. Higher up, they form overhanging sections until they collapse by mass movement.
What is cliff slumping?
Slumping: involves a whole segment of the cliff moving down-slope along a saturated shear-plane. Soil Creep: the slowest of downhill movements, occurring on very gentle and well-vegetated slopes. Although material may move by less than 1 cm a year, its results can be seen in step-like terracettes on hillsides.
Is clay a hard or soft rock?
The soft rock is made of clay and sands, and the hard rock is chalk and limestone.
Is sandstone a hard or soft rock?
Most sandstones are made up largely of quartz grains, because quartz is a very hard and chemically-resistant mineral. Quartzite is a name given to very hard, pure quartz sandstones. Many sandstones contain some grains of other minerals like calcite, clay, or mica.
What are cliff features?
A cliff is a mass of rock that rises very high and is almost vertical, or straight up-and-down. Cliffs are very common landscape features. They can form near the ocean (sea cliffs), high in mountains, or as the walls of canyons and valleys. Cliffs are usually formed because of processes called erosion and weathering.
What are micro features of a cliff?
Micro-features are small-scale coastal features such as caves and wave-cut notches which form part of a cliff profile. They form in areas weakened by heavy jointing, which have faster rates of erosion, enlarging the joint to form a sea cave.
What is rotational cliff slumping?
A rotational slump occurs when a slump block, composed of sediment or rock, slides along a concave-upward slip surface with rotation about an axis parallel to the slope. The cut which forms as the landmass breaks away from the slope is called the scarp and is often cliff-like and concave.
What is sliding geography?
A slide happens when a section of soil or rock suddenly gives way and moves down a slope. The material moves as a single mass along a slippery zone. The slippery zone is often made up of wet sediment . Translational slides move along a flat slippery zone.
What rocks are hard and soft?
A term applied to hard rocks, or igneous and metamorphic rocks that are distinguished from sedimentary rocks because they are typically more difficult to disaggregate. Well cemented sedimentary rocks are sometimes described as being hard, but are usually called soft rock.
What are the soft rocks?
These soft rocks include argillaceous feldspar quartz fine sandstone, calcareous argillaceous siltstone, argillaceous siltstone, iron-stain argillaceous calcareous siltstone, iron-stain argillaceous calcareous feldspar lithic sandstone, and mudstone.
How are steep cliffs formed and how are they formed?
Steep cliffs are formed where the land consists of hard, more resistant, rocks, their height obviously being determined by the difference between the sea level and the level of the land. Hard rocks erode and weather slowly, and the less fractured the rock is, the better it will resist breaking down.
What makes a rock different from a cliff?
A smooth angled surface will better resist waves than a rough broken surface, so the same rock can form different types of cliff according to how the rock surfaces face the sea. Generally though, remember that hard rocks form steep cliffs and soft rocks and badly broken/fractured rocks form more gently sloping cliffs.
What kind of landforms are formed by cliff retreat?
As a consequence of cliff retreat another landform. The wave-cut platform, is formed. Headlands and bays, such as Swanage Bay, form on discordant coastlines, where hard and soft rock run in layers at 90˚ to the water.
Which is erosional landforms have a lower cliff profile?
Weaker rocks (e.g. clays and sands) have less structural, strength and are eroded easily, producing a lower cliff profile with mudslides and slumping. Concordant (rock type runs parallel to the sea). Often produce straighter coastlines. Discordant (rock type runs perpendicular to the sea). Often produce headlands and bays.