Lonar Crater

• 12 Jun 2020

Why in News

Recently, the water in the Lonar lake in the Buldhana district of Maharashtra was found to be turning reddish over the past few days.

• The local administration of the district has requested the National Environmental Engineering Research Institute (NEERI), Nagpur, to find out the reason behind it.

Key Points

• The colour of water in Maharashtra's Lonar lake, also known as Lonar crater, has changed to red.
• It is said to be normal when the lake gets rainwater.
• Probable Reasons:
  
  • Algal Bloom:
    
    • An algal bloom or algae bloom is a rapid increase or accumulation in the population of algae in freshwater or marine water systems, and is often recognized by the discoloration in the water.
    • Change in colour is generally attributed to algal bloom in the lake around the time of monsoon.
  • Change in Salinity:
    
    • Due to the evaporation of water, the salinity in the water has increased. Hence, it is believed to be a factor behind the change in colour.
  • Biological Change:
    
    • The colour change seems to be a biological change in the Lonar crater as during the lockdown phase, there was no disturbance to the lake and naturally it has turned red.

Lonar Lake

• Lonar Lake, also known as Lonar crater, is a notified National Geo-heritage Monument, saline, soda lake, located at Lonar in Buldhana district, Maharashtra.
  
  • Geo-heritage refers to the geological features which are inherently or culturally significant offering insight to earth’s evolution or history to earth science or that can be utilized for education.
  • Geological Survey of India (GSI) is the parent body which is making efforts towards identification and protection of geo-heritage sites.
• It is situated inside the Deccan Plateau—a massive plain of volcanic basalt rock created by eruptions.
• It is believed to have been created over 52,000 years ago when a meteorite hit the Earth.
• It is formed in basaltic rock with a diameter of 1.85 km and depth of 500 feet.

Source: IE