Geology of a recently terraformed planet

Consider a planet that's broadly Earthlike in size, rotation,
insolation, etc. But it's either lifeless, or has only anaerobic
bacteria. Like Earth in the deep Precambrian, it has a reducing
atmosphere.

Human colonists arrive and terraform it -- algae, then invertebrates,
fungi, land plants, and on up the food chain.

Let us say this takes a thousand years; at the end of which time the
planet has a breathable atmosphere, topsoil, and enough free-living
plants and animals for a human to survive by hunting and fishing.

Now: how will it be different? from Earth?

1) No fossil fuels. FFs were created over millions of years; there
hasn't been time for that here. No oil, natural gas, or coal. Not
even peat.

2) No limestone; limestone is made from the shells of microscopic
marine animals. So, no marbe -- that's just limestone metamorphized
by heat and pressure. (Marble may be a fantastically valuable luxury,
available only as an import from Earth). No limestone caves, either.

3) The soils will be different. Topsoil, okay, but it won't be that
deep except in places where there's been a special effort to create it;
under ideal conditions, prairie topsoil "grows" at something like an
inch per century. And there are hardly any clays... clays are
biogenic; a clay may be 50% organic material by mass.

4) The climate may be very unstable. A thousand years is probably not
long enough to generate a long-term stable climate equilibrium. To
give just one example, a functioning biosphere will shunt a huge amount
of CO2 out of the atmosphere, which will tend to cool the planet.
Eventually it recycles back, thanks to plate tectonics, but there won't
have been nearly enough time for that. Even the weathering cycle may
still be wobbling chaotically. IMS it's something like this that caused
Snowball Earth in the Precambrian.

What else?


Doug M.

.

Relevant Pages

  • When.
    ... Earth History Of 1.35 Million Years. ... we were doing on this planet in the past. ... Australia - when then 58 year old Michel ... My name is Thao, but first, I would like ...
    (talk.religion.newage)
  • When.
    ... Earth History Of 1.35 Million Years. ... we were doing on this planet in the past. ... Australia - when then 58 year old Michel ... My name is Thao, but first, I would like ...
    (sci.skeptic)
  • When.
    ... Earth History Of 1.35 Million Years. ... we were doing on this planet in the past. ... Australia - when then 58 year old Michel ... My name is Thao, but first, I would like ...
    (alt.religion.christian)
  • Was.
    ... Earth History Of 1.35 Million Years. ... we were doing on this planet in the past. ... Australia - when then 58 year old Michel ... My name is Thao, but first, I would like ...
    (alt.religion.christian)
  • Was.
    ... Earth History Of 1.35 Million Years. ... we were doing on this planet in the past. ... buzz your core...as you see life from a ... Australia - when then 58 year old Michel ...
    (talk.religion.newage)