BY PETER J. SMITH
Department of Earth Sciences
Milton Keynes, U.K.
" Data from isotopes and incompatible elements show that the Kolar Schist Belt in southern India’s Dharwar Craton is a suture zone marking the accretion of distinct terrains during the Archean. Plate-tectonic processes were thus shaping the Earth’s crust as early as 2500 million years ago.
EJ. Krogstad, S. Balakrishnan, D.K. Mukhopadhyay, V. Rajamani, G.N. Hanson, “Plate tectonics 2.5 billion years ago: evidence at Kolar, south India,” Science, 243, 1337-40, 10 March 1989. (State University of New York, Stony Brook; Jawaharlal Nehru University, New Delhi, lndia Roorkee University, Rcorkee, India)
" The proliferation and increased diversity of angiosperm-deciduous ecosystems during the late Cretaceous must have led to higher rates of mineral weathering. This would have increased the environmental concentration of carbonate-forming ions, reducing. atmospheric CO2 and leading to global cooling (by up to 1O...