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Terrestrial Analogues for Early Planetary Oceans: NIUAFO‘OU CALDERA LAKES (Tonga) and Their Geology, Water Chemistry, and Stromatolites

2012; Springer Nature (Netherlands); Linguagem: Inglês

10.1007/978-94-007-4966-5_13

1566-0400

Stephan Kempe, J. Kaźmierczak,

Methane Hydrates and Related Phenomena

Earth is a unique planet in a special planetary system to have not only made biogenesis possible but also to sustain life’s long-term evolution toward multi­cellularity and self-recognition. The reconstruction of Earth’s history relies on evidence recovered from its rock record. From this record, we know that life originated prior to 3.8 Ga (e.g., Schidlowski et al., 1979; Mojzsis et al., 1996), that multicellular life arose at around 0.6 Ga, and that biologically controlled, enzymatic biomineralization started with the beginning of the Phanerozoic eon, at around 0.54 Ga ago (e.g., Lowenstam and Margulis, 1980; Simkiss, 1989). Geochemical forcing most probably triggered these events (Kazmierczak and Degens, 1985; Kazmierczak et al., 1985; Kempe and Degens, 1985; Kempe and Kazmierczak, 1994; Kazmierczak and Kempe, 2004; Brennan et al., 2004). The nature of this forcing, however, remains unknown, and one can only formulate working hypotheses. The Earth system is governed by too many parameters, excluding the possibility of building models, which, by representing all the physical interactions, would create life. Therefore, we rather have to ask, what are the necessary environmental conditions under which life could have been initiated and can we find such environments even today in order to study these primordial conditions?