Trichy Rockfort Hill Complex,TN Is About 3 To 4 Billion Years Old - Made of Oldest Basement Rocks in the World

Navrang India November 20, 2024

1858 image, Trichy, (Madras Presidency), oldindianphotos.in

Above image:  On the southern face of the Rock are cave temples dating from the time of the Pallava king Mahendravarman I (reigned 570-630) and the Pandya period (8th century). On the west face is the 17th century Thayumanaswamy temple dedicated to Shiva, Lingam in the sanctum, it is said, is a natural.This photo was taken when 1857-58  revolt (Sepoy Mutiny) was widespread  in North Indian states against the English Co.  Photo by: Linnaeus Tripe 

1868 image Trichy Rockfort Complex. oldindianphotos.in

1870 image photo. E.D Lynn Trichy Rockfort, TN past-india.com 

Above image; Old image of Tiruchirappalli city's Rockfort Hill adivaram (bottom area), now a famous bazaar area; photo taken when India came under the British Crown. under Queen Victoria (since1860)

The Rockfort of Tiruchirappalli

The Rockfort in Tiruchirappalli city's prime area inside the  Main Guard Gate,Tamil Nadu, is the city's most iconic monument and a geological marvel. Rising 83 meters above the flat plains where the Cauvery delta begins, this ancient outcrop is a testament to Earth's deep history. Composed of Archean igneous rocks,  (formed way inside the earth crust) the hill dates back approximately 3.5 billion years, making it one of the oldest rock formations in the world. These rocks are much older than the Vindhyan ranges and the Himalayan mountains, which are of more recent sedimentary origin. Whenever you climb the steps to reach the Shiva and Ganapati Temples on the rockfort hill, remember you are walking on the hard rocks that were formed during the earliest consolidation of the Earth Planet  the oldest in the world. These rock are known as Basement Rocks upon which other rock formations were evolved along with the evolution of life. Other examples are Canadian Shields and others in Africa. 

The Rockfort hill is predominantly made up of granite, a type of igneous rock formed deep within the Earth's crust. Quartz and feldspar are the main constituents of this granite. Such formations occurred during the Archean Eon, a period in Earth's history when the planet's crust was still stabilizing. The presence of these rocks in Tiruchirappalli connects the city to the planet's earliest geological events. The other Granitic outcrop lies on the way to Thanjavur city near Tiruvaranbur. Atop the hill lies a Hindu temple. 

Beyond its geological significance, the Rockfort is home to 7th century temples of great historical and cultural importance. The Ucchi Pillayar Temple (7th CE) dedicated to Lord Ganesha, and the 17th Ce  Thayumanaswami Temple, dedicated to Lord Shiva, are situated atop this hill. Reaching the summit involves climbing 437 steep steps carved into the rock, a journey that offers stunning views of the city and surrounding plains.

Archean Rocks and Their Origin

 roughly 3 to 4 billion years ago Archean earth
 media.sciencephoto.com
slideshare.com Archaean complex rocks

Archean rocks are the Earth's oldest formations, originating between 4 and 2.5 billion years ago. They primarily consist of igneous and metamorphic rocks like granite and gneiss, formed during the planet's early cooling phase. During the Archean Eon, Earth's crust was forming, and volcanic activity was rampant. These rocks are rich in minerals like quartz and feldspar and provide valuable insights into the Earth's early tectonic and atmospheric evolution. Archean terrains are rare and significant for understanding Earth's ancient history.