By B R Manjunatha and C Krishnaiah
The authors are Asso. Professors, Ocean Science and Technology Cell and Department of Marine Geology, Mangalore University, respectively, Mangalagangotri. email@example.com
Many people were worried about the possibility of a natural calamity towards the end of 2012 leading the human race to perish. Perhaps the first predictions rose from Mayan astrology – chalked out in a calendar built out of stones indicating an abrupt end of the world on 21 December 2012. But, mass extinction on Earth needs to take clues from a geological perspective to be anywhere near the truth.
From the violent beginning of the earth, it took nearly 800 mega-annum (Ma) to cool down (Hadean Eon). Igneous and metamorphic rocks from 3800 Ma to 2500 Ma (Archaean Eon) were formed principally followed by sedimentary rocks from 2500 Ma to 570 Ma (Proterozoic Eon) and mixed rock types on land as well as in the oceans from 570 Ma to the present (Phanerozoic Eon). The understanding of the origin of life and its commencement during the Archaean Eon is...