Lonar crater

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The southwest side of Lonar crater.

Lonar crater in a impact crater situated in the Buldhana district of the Indian state of Maharashtra. The crater is 1.83 km (6,000 ft) in diameter and 170 metres in depth, and its age is estimated to be 52,000 ± 6,000 years (Pleistocene). It is the largest impact crater in basaltic rock and is partially filled by a salt water lake.

[edit] Geographic location

Lonar crater is situated around 550 km from Mumbai, 160 km from Aurangabad and 140 km from Buldhana. It is about 4½ hours drive southeast of the famous Ajanta Caves. The nearest railway station is Malkapur on Bhusaval-Nagpur Section of SC Railway.

[edit] Origin

Although once thought to be of volcanic origin, Lonar crater is now recognized as an impact crater created by the hypervelocity impact of either a comet or meteorite. The impact origin of this crater is clearly demonstrated by the presence of plagioclase that has been either converted into maskelynite or contains planar deformation features (PDFs). Only shock metamorphism caused by hypervelocity impact can transform plagioclase into maskelynite or create PDFs. The impact origin of Lonar crater is further substantiated by the presence of shatter cones, impact deformation of basalt layers comprising its rim, shocked breccia inside the crater, and non-volcanic ejecta blanket surrounding the crater.