4Pavlov A A, Kasting J F. Mass-independet fractionation of sulfer isotope in Archean sediments: Strong evidence for an anoxic Archean atmosphere. Astrobiology, 2002, 2:27-41.
5Kirschvink J L, Gaidos E J, Bertani L E. Paleoproterozoic snowball Earth: Extreme climatic and geochemical global change and its bio- logical consequences. Proc Natl Acad Sci USA, 2000, 97:1400-1405.
6Evans D A, Beukes N J, Kirschvink J L. Low-latitude glaciation in the Palaeoproterozoic era. Nature, 1997, 386:262-266.
7Kopp R E, Kirschvink J L, Hilburn I A, et al. The paleoproterozoic snowball Earth: A climate disaster triggered by the evolution of oxy genic photosyntheis. Proc Natl Acad Sci USA, 2005, 102:11131-11136.
8Barley M E, Bekker A, Krapez B. Late Archean to Early Paleoproterozoic global tectonics, environmental change and the rise of atmos- pheric oxygen. Earth Planet Sci Lett, 2005, 238:156-171.
9Hayes J M. Global methanotrophy at the Archean-Proterozoic transition. In: Bengston S, ed. Early Life on Earth. Vol 84. New York: Co- lumbia University Press, 1994. 220-236.
10Pavlov A A, Kasting J F, Brown L L. Greenhouse warming by CH4 in the atmosphere of early Earth. J Geophys Res, 2000, 105: 11981-11990.