The outgassed atmosphere

In stage 2, the gases are Ni, HjO, CO2 and SO2 with only very small amounts of Hi. The ratios Eire  

Summary of data on the probable chemical composition of the atmosphere (from Holland, 1962) for explanation see text. 

A serious consideration is whether iron could have remained in equilibrium with volcanic source rocks for a significant period of time. Holland (1962) suggests 500 X 10 years as an upper limit. However, more recent models for early core formation would reduce this period to perhaps 100 X 10 years (Fanale, 1971). There are also other objections to this model, among which is the hypothesis that core formation occurred prior to the Earth s acquisition of a volatile-rich coat (Turekian and Clark, 1969 Walker, 1976). If the formation of the first biologically interesting organic 

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