Context

• Recently, the 56,000-year-old Lonar crater sanctuary lake in Buldhana district of Maharashtra state has turned dark pink.
• Lonar Lake is famous as the world’s Largest Basaltic Impact Crater.
• Similar phenomenon of the water in the lake turning dark pink takes place in Umria lake in Iran.

About Lonar Lake

• Also known as Lonar crater is a saline, usually called as soda lake,
• located at Lonar in Buldhana district, Maharashtra.
• a notified National Geo-heritage Monument.
• created by an asteroid collision with earth impact during the Pleistocene Epoch.
• one of the four known, hyper-velocity, impact craters in basaltic rock anywhere on Earth.
• Situated inside the Deccan Plateau that’s a massive plain of basalt rock. The other three basaltic impact structures are in southern Brazil.
• Its unusual geochemistry enables the growth of specific types of microorganisms, some of which are not found anywhere else.
• The water is both saline and alkaline in nature, which makes it unique

About NGM

• National Geological Monuments are geographical areas of national importance and heritage, as notified by the Government of India’s Geological Survey of India (GSI), for their maintenance, protection, promotion and enhancement of geotourism.
• There are 34 notified National Geological Heritage Monument Sites of India.
• GSI or the respective State governments are responsible for taking necessary measures to protect these sites.

Important Facts to remember

Observations (Why Pink Colour?)

• Highly alkaline, which means high concentration of carbonate salts,
• saline chemistry support the growth of a family of bacteria known as Halobacteria. Halobacteria is not harmful to humans.
• These organisms thrive in highly saline conditions, producing a red pigment that absorbs sunlight and converts it into energy. 
• Some think presence of Dunaliella salina microalgae. Dunaliella produces carotenoids, a pigment found in carrots as well.

UNESCO Global Geopark

• single, unified geographical areas where sites and landscapes of international geological significanceare managed with a holistic concept of protection, education and sustainable development.
• not a legislative designation
• does not imply restrictions on any economic activity inside the site
• No Indian site is in the list till now.

Difference between UNESCO Global Geoparks, Biosphere Reserves and World Heritage Sites:

• Biosphere Reservesfocus on the harmonized management of biological and cultural diversity.
• World Heritage Sitespromote the conservation of natural and cultural sites of outstanding universal value
• UNESCO Global Geoparksgive international recognition for sites that promote the importance and significance of protecting the Earth’s geodiversity through actively engaging with the local communities.
• A World Heritage Site or Biosphere Reserve can apply for the UNESCO Global Geopark status. However, a clear evidence has to be provided on how UNESCO Global Geopark status will add value by being both independently branded and in synergy with the other designations.

Global Geoparks Network (GGN):

• The Global Geoparks Network (GGN), of which membership is obligatory for UNESCO Global Geoparks,is a legally constituted not-for-profit organisation.
• The GGN was founded in 2004 and is a dynamic network where members exchange ideas of best practice to raise the quality standards of a UNESCO Global Geopark.
• While the GGN as a whole comes together every two years, it functions through the operation of regional networks, such as the European Geoparks Networkthat meets twice a year to develop and promote joint activities. It is managed under the UNESCO’s Ecological and Earth Sciences Division.