a) The cooling and solidification of the upper crust of the earth surface marked the earliest phase of tectonic evolution in the Archaean era (prior to 2.5 billion years) which is represented by the exposure of gneisses and granites especially on the Peninsula. These form the core of the Indian craton.
b) The Aravalli Range is the remnant of an early Proterozoic orogeny called the Aravalli-Delhi orogeny that joined the two older segments that make up the Indian craton.
c) The erosion of the mountains and further deformation of the sediments of the Dharwarian group marks the second phase. The volcanic activities and intrusions, associated with this second phase are recorded in composition of these sediments.
d) Early to Late Proterozoic calcareous and arenaceous deposits, which correspond to humid and semi-arid climatic regimes, were, deposited the Cuddapah and Vindhyan basins. These basins, which border or lie within the existing crystalline basement, were uplifted during the Cambrian (500 Ma).
e) The Vindhyans are believed to have been deposited between around 1700 and 650 Ma. Early Palaeozoic rocks are found in the Himalayas and consist of southerly-derived sediments eroded from the crystalline craton and deposited on the Indian platform.
f) In the Late Paleozoic, Permo-Carboniferous glaciations left extensive glacio-fluvial deposits across central India, in new basins created by sag/normal faulting. These tillites and glacially derived sediments are designated the Gondwana series.
The sediments are overlain by rocks resulting from a Permian marine transgression (270 Ma).
The late Paleozoic coincided with the deformation and drift of the Gondwana super-continent.
To this drift, the uplift of the Vindhyan sediments and the deposition of northern peripheral sediments in the Himalayan Sea can be attributed.
b) The Aravalli Range is the remnant of an early Proterozoic orogeny called the Aravalli-Delhi orogeny that joined the two older segments that make up the Indian craton.
c) The erosion of the mountains and further deformation of the sediments of the Dharwarian group marks the second phase. The volcanic activities and intrusions, associated with this second phase are recorded in composition of these sediments.
d) Early to Late Proterozoic calcareous and arenaceous deposits, which correspond to humid and semi-arid climatic regimes, were, deposited the Cuddapah and Vindhyan basins. These basins, which border or lie within the existing crystalline basement, were uplifted during the Cambrian (500 Ma).
e) The Vindhyans are believed to have been deposited between around 1700 and 650 Ma. Early Palaeozoic rocks are found in the Himalayas and consist of southerly-derived sediments eroded from the crystalline craton and deposited on the Indian platform.
f) In the Late Paleozoic, Permo-Carboniferous glaciations left extensive glacio-fluvial deposits across central India, in new basins created by sag/normal faulting. These tillites and glacially derived sediments are designated the Gondwana series.
The sediments are overlain by rocks resulting from a Permian marine transgression (270 Ma).
The late Paleozoic coincided with the deformation and drift of the Gondwana super-continent.
To this drift, the uplift of the Vindhyan sediments and the deposition of northern peripheral sediments in the Himalayan Sea can be attributed.
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