Rare columnar basalts found near Pochera waterfalls

HYDERABAD: Geology and archaeology enthusiasts have found ‘columnar basalts’ — natural sculpture-like rock formations formed th-rough the heating and cooling of melted volcanic lava containing basalt — close to Pochera waterfalls in Pochera village of Boath mandal in Adilabad district. The rare rock formations were found by K Murali and other members of Kotha Telangana Charitra Brundam.

The ‘Deccan Traps’ formed 6.5 crore years ago due to the slow emplacement of volcanic flows during eruptions lasting for years, covers 5 lakh sq km in west-central India, is known among the largest volcanic provinces in the world.The first time columnar basalts were discovered in the Deccan Traps region was in 2015, in Gudihathnoor mandal of Adilabad district.

Columnar basalts look like long cylinders in hexagonal shape which are formed during the cooling and contracting of lava. They usually take shape from the top down into the middle or even bottom of the lava flow. They can be perfectly hexagonal with six sides, or can even have five or seven sides.

When the columnar basalts form regular hexagonal long straight column patterns, they are called ‘colonnade,’ and when they are more irregular in shape and are imperfect, they are called ‘entablature.’
One of the best examples of colonnade basalts is the Devil’s Tower in the US and the ones in Ireland. According to Ch Venugopal, former deputy director general of Geological Survey of India, the newly discovered columnar basalts of Pocherla are entablature.

“It is difficult to recognise this pattern due to its fractured nature and lacking a dominant orientation of columns. Hence, the columnar basalts look special and deserve further attention, as the cooling and emplacement history of lava can be best studied in this section of the Deccan Traps. Just like the columnar basalts in the US and Ireland which have been well-preserved, this particular site in Pochera needs to be declared a geologically protected site,” Venugopal opined.