Young Sun, Early Earth and the Origins of Life

Long-term eustatic cyclicity in the Paleogene: a critical assessment

“…Such an interpretation is in agreement (at least, in part) with the outcome of modelling undertaken recently by Coltice et al (2014). The above-mentioned and other peculiarities of the Precambrian tectonics (including, first of all, the activity of mantle plumes (Gargaud et al, 2012;Gerya, 2014)) likely influenced global sea-level change on a large scale; possible changes in the crust production may also induce a cyclic pattern of these changes (Eriksson et al, 2004(Eriksson et al, , 2005(Eriksson et al, , 2012. For the earliest times, this second line of evidence is most uncertain, because the onset of the plate tectonics on the Earth remains debatable (e.g., Hamilton, 2011;Gargaud et al, 2012;Griffin et al, 2014;Turner et al, 2014).…”

“…It cannot be excluded that the same might have also occurred for earlier Precambrian glaciations (Eriksson et al, 2004;Eyles and Januszczak, 2004;Gardaud et al, 2012;Strand, 2012;Hoffman, 2013;Melezhik et al, 2013;Tang and Chen, 2013;Young, 2013). Secondly, the size of lithospheric plates in the Proterozoic and, especially, the Archean and the Hadean, as well as the size of the Precambrian supercontinents, was relatively small (Pesonen et al, 2003;Ernst, 2007Ernst, , 2009Komiya and Maruyama, 2007;Gargaud et al, 2012;Evans, 2013). This may imply a wider distribution of young domains of the oceanic crust than in the Phanerozoic.…”

“…The above-mentioned and other peculiarities of the Precambrian tectonics (including, first of all, the activity of mantle plumes (Gargaud et al, 2012;Gerya, 2014)) likely influenced global sea-level change on a large scale; possible changes in the crust production may also induce a cyclic pattern of these changes (Eriksson et al, 2004(Eriksson et al, , 2005(Eriksson et al, , 2012. For the earliest times, this second line of evidence is most uncertain, because the onset of the plate tectonics on the Earth remains debatable (e.g., Hamilton, 2011;Gargaud et al, 2012;Griffin et al, 2014;Turner et al, 2014). Thirdly, the amount of water on the Earth did not remain constant at the earliest stages of the planetary evolution (Gargaud et al, 2012), which also means significant global sea-level changes (although the latter, probably, will never be modelled).…”

“…For the earliest times, this second line of evidence is most uncertain, because the onset of the plate tectonics on the Earth remains debatable (e.g., Hamilton, 2011;Gargaud et al, 2012;Griffin et al, 2014;Turner et al, 2014). Thirdly, the amount of water on the Earth did not remain constant at the earliest stages of the planetary evolution (Gargaud et al, 2012), which also means significant global sea-level changes (although the latter, probably, will never be modelled). Fourthly, a slow drain of water into the interiors should be considered as a long-term control on the global sea-level changes (Conrad, 2013;Maruyama et al, 2014).…”

Hypothesis, analysis and synthesis, it's all Greek to me

“…Better names might have been endogenomics for the study of environmental samples taken from inside a host organism, and exogenomics for the study of samples taken from the outside (endo- and exo- meaning 'inside' and 'outside' in Greek, respectively). A similar situation might have occurred when looking for a name to describe the search for life elsewhere in the universe: the term exobiology was gradually replaced by astrobiology (Gargaud et al, 2011) – possibly because it had to rhyme with astronauts!…”