tigertiger?
I am intrigued about this 'de-gassing episode'. Are you talking about the Late Heavy Bombardment, which I did not think was associated with excessive atmosphere loss? If not, could you provide me with a link to any evidence or discussion of it?
You are right Dodgy Geezer.
I have just realised that I miss read the text book all those years ago.
I misread ‘the atmosphere was formed after the degassing of the planet’, to mean that, the atmosphere was re-formed after being ‘lost’.
What it actually means is that the hot lump of rock (Earth) was losing gas (degassing) as it cooled.
The remainder of the statement about the atmosphere, and the processes of change is I believe still correct.
The gases were mostly of the volcanic variety, not being conducive to life as we know it.