Without Geography you are nowhere !!!

Corals are not plants but animals 😕 !! Corals are the simplest animals. They do not have organs,such as heart. They belong to phylum Cnidaria,a group of invertebrates which also includes the Jellyfish. Corals are made up of tiny organisms called Polyps. The polyps are soft-bodied but secrete limestone skeletons for support. Large, iconic reefs are formed when many, many polyps come together and build on one another.  Coral reefs get their colorful hues from algae called zooxanthellae. The coral polyps themselves are actually see-through! Polyps and zooxanthellae have a symbiotic relationship, where coral polyps get their food and color from the algae in exchange for providing housing and protection to the algae. Hard corals are the primary reef-building corals. Hard corals that form reefs are called hermatypic corals. Soft coral, also known as Alcyonacea and ahermatypic coral, do not produce a rigid calcium carbonate skeleton and do not form reefs.  Prec

In the previous post we learned about the beautiful world of coral reefs. Time to move on to their types. Basically there are 3 types of coral reef structures :- 🔵 Fringing Reefs    🔵 Barrier Reefs     🔵 Atolls .  As reefs mature, they can develop from fringing reefs to barrier reefs to atolls. 🔵 Fringing Reefs ► They are the most common type of reefs. They are located very close to land, and often form a shallow lagoon between the beach and the main body of the reef.They are often relatively young reefs and tend to be best developed on stable or rising coasts. Fringing reefs are most common in Caribbean sea and Red sea. According to Darwin, Fringing reefs are the first kind of reefs to form around a landmass in a long-term reef growth process.  In India, it is seen in the Gulf of Munnar, Palk Bay, and in the western part of Andaman and Nicobar islands. In the west coast of India fringing reefs are seen in the Malvan coast and in the Gulf of  Kutch including Pirotan island.

The subject of the origin of coral reefs has been debated for our one and a half centuries and several theories  have been put forward but none has been universally accepted. Some major ones are:- 1)  Subsidence theory of Charles Darwin   ►According to it, all coral reefs develop due to growth of polyps at shallow depths because at greater depths they cannot survive. Fringes -Barrier -Atolls are successive stages of coral reefs development. First, polyps grow at suitable stage below sea level and develop to form fringing reefs. After, land is subjected to subsidence due to tectonic forces,thus coral reefs reach greater depths where  they may not survive. The growth of polyp is retarded near the coastal land but is vigorous at the outer edges of the land.  Consequently, a lagoon is formed between coastal land and reef, hence the Barrier reef. Further subsidence of land and island is completely submerged under water and a ring of coral reef in the  form of atoll is formed. Depth

                              Anabatic = moving upwards ;    Katabatic = moving downwards . Anabatic winds which  flow upslope of a mountain from lower valleys  develop during daytime in calm sunny weather. They are    warm winds which blows up a steep slope or  mountain  side, driven by heating of the slope through  insolation .   Air which is in contact with slopes that are warmed expands upward and cool and sinks over neighbouring valleys. Anabatic winds are usually slow , at only 1-2m/s and are rarely important expect near coasts where they can increase the strength of sea breezes.   Anabatic winds are particularly useful to soaring  glider  pilots who can use them to increase the aircraft's altitude. Anabatic winds can be detrimental to the maximum downhill speed of cyclists.      Katabatic winds are  downslope winds  flowing from high elevations of mountains, plateaus, and hills down their slopes to the valleys or plains below. During and after sunset ,

 The Continental drift theory by Alfred Wegner tells that the continents are on the move but fails to explain the actual cause of this movement. Thanks to the Plate Tectonics theory and the Sea Floor Spreading theory we now know what actually causes this movement !! From the deepest ocean trench to the tallest mountain, plate tectonics explains the features and movement of Earth's surface in the present and the past. The Earth's crust is  not uniform and is broken into many smaller pieces called "Lithospheric Plates" .The term 'Lithosphere' includes the earth's crust and the upper mantle. These plates can either be the "Oceanic" plate or the "Continental" plate. These plates float on the inner mantle due to the convection currents occuring inside the mantle.  C onvection currents  describe the rising, spread, and sinking of gas, liquid, or molten material caused by the application of heat.  eg. ->  Inside a beaker, hot water ri

Theory holds that the mantle is able to convect because of its plasticity, and this property also allows for another very important Earth process known as  isostasy . The literal meaning of the word isostasy  is “ equal standstill ”,ie. to maintain equilibrium.  The general term 'isostasy' was coined in 1882 by the American geologist  Clarence Dutton . Isostasy  is the rising or settling of a portion of the Earth's lithosphere that occurs when weight is removed or added in order to maintain equilibrium between buoyancy forces that push the lithosphere upward and gravity forces that pull the lithosphere downward. Thus  Isostasy is based on the opposing influences of two main forces: buoyancy and gravity. This concept is invoked to explain how different topographic heights can exist at Earth's surface. When a certain area of Earth's crust reaches the state of isostasy, it is said to be in  isostatic equilibrium . Isostasy does not upset equilibrium but instead res