Wave/ Current/ Tides – Coastal Landforms

-
Other than the action of waves, the coastal landforms depend upon
  1. the configuration of land and sea floor;
  2. whether the coast is advancing (emerging) seaward or retreating (submerging) landward
Concept of evolution of coastal landforms:
  1. High, rocky coasts (submerged coasts);
  2. low, smooth, and gently sloping sedimentary coasts (emerged coasts).
High rocky coasts
  • River drowned with highly irregular coastline. hill sides drop off sharply into the water.
  • Shores do not show any depositional landforms initially. Erosion features dominate.
  • With constant pounding by waves, the cliffs recede leaving a wave-cut platform in front of the sea cliff.
  • The materials which fall off, and removed from the sea cliffs, gradually break into smaller fragments and roll to roundness, will get deposited in the offshore.
  • Deposit in the offshore, a wave-built terrace would develop in front of wave-cut terrace.
  • Bars are submerged features and Barrier bars – Bars shown up above water.Barrier bar which get keyed up to the headland of a bay is called a spit. When barrier bars and spits form at the mouth of a bay and block it, a lagoon forms.
Low sedimentary coasts
  • A long low sedimentary coasts the rivers appear to extend their length by building coastal plains and deltas. Depositional features dominate.
  • Bottom sediments get churned and move readily building bars, barrier bars, spits and lagoons.
  • The west coast - high rocky retreating coast. Erosional forms Dominate.
  • The east coast - low sedimentary coast. Depositional forms dominate.
Erosional Landforms
Cliffs, Terraces, Caves and Stacks
  • Wave-cut cliffs and terraces are two forms usually found where erosion is the dominant shore process.
  • Platforms occurring at elevations above the average height of waves is called a wave cut terrace.
  • Lashing of waves against the base of the cliff and the rock debris that gets smashed against the cliff along with lashing waves create hollows and these hollows get widened and deepened to form sea caves.
  • Resistant masses of rock, originally parts of a cliff or hill are called sea stacks.
Depositional Landforms
Beaches and Dunes
  • Characteristic of shorelines that are dominated by deposition. Occur as patches along even the rugged shores.
  • Shingle beaches contain excessively small pebbles and even cobbles.
Bars, Barriers and Spits
  • Parallel to the coast is called an off-shore bar.
  • off-shore bar which is exposed due to further addition of sand is termed a barrier bar.
  • Splits - Barrier bars get keyed up to one end of the bay.

Comments

Post a Comment

Popular posts from this blog

Indian Painting - Pre History

-
Image
    History and Evolution of Painting in India - An Overview India has a long tradition of artistic excellence and painting is one of the major mediums that has been used to express it. There is several evidence suggesting that painting flourished in India since ancient times. Archaeologists have found wall paintings in parts of India, which suggest that even the early historic man in India was engaged in activities of art and leisure The history of painting can be traced through the ancient and medieval period where the books were illustrated with paintings Then came the miniature style that dominated the Mughal and Rajput courts. With the coming of the Europeans, the art of painting and engraving took a western turn. Modern painters experimented with styles, colours and designs. Many Indian painters have gained worldwide recognition and are winning prizes and accolades for their vision. Principles of Painting The history of paintings can be known from primitive rock paintings of Bhim
Read more

Classification of Indian Paintings

-
Image
    Classification of Indian Paintings Indian Paintings have been broadly classified into two. Mural Paintings Miniature Paintings Mural Paintings The work on the walls or a solid structure are referred to as Murals. These have existed in India since ancient times and can be dated between 10th century BC and 10th century AD. The evidence of such paintings can be found at several locations in India. The beauty and the exquisiteness of mural paintings can be seen in places like Ajanta, Armamalai Cave, Ravan Chhaya Rock Shelter, Bagh Caves, Sittanavasal Caves and Kailash Temple in Ellora. Most of the mural paintings are either in natural caves or in rock cut chambers. The paintings follow a theme, the most common being Hindu, Buddhist and Jain. Mural paintings were also made to adorn any mundane premise. For e.g. Ancient theatre room in Jogimara Caves. Ajanta Cave Paintings One of the oldest surviving murals of Indian sub-continent, Ajanta caves were carved between 2nd century BC to 5th c
Read more

Folk Paintings

-
    Madhubani Paintings Traditionally done by the women of villages around Madhubani town (Bihar). It is also called Mithila Paintings. The paintings have a common theme and are usually drawn from religious motifs of the Hindus, including Krishna, Rama, Durga, Lakshmi and Shiva. The paintings are also made depicting auspicious occasions like birth, marriage and festivals. Flowers, trees, animals, etc. are used to fill any gaps in the painting. Traditionally, these were painted on walls using rice paste and vegetable colours on a base of cow dung and mud. With time, the base changed to handmade paper, clothes and canvas. Since there was no shading, the paintings are two-dimensional. Some of the common features of these paintings include double line border, bold use of colours, ornate floral patterns and exaggerated facial features. Since the art has remained confined to a specific geographical area, it has been given GI (geographical indication) status. Pattachitra Painting A traditiona
Read more