Why does Safehold have coal and petroleum?

I'm on my first way through the series, and I'm up to _Midst Toil and Tribulation_. It seems likely someone's asked this already, so please point me there if I've missed it.

Why does Safehold have fossil fuels? Was it Earthlike enough to generate them from plant matter? Did the terraforming team put it there?

Safehold already had a functioning ecolosystem. The process of "Sanctifying" land is actually "Kill off the native stuff and introduce the stuff the 'Angels' modified".

I believe the question is how can oil form unless the organisms that dies have very similar chemistry to that of Earth. If the chemistry is different enough, oil *can't* form no matter how the mass of organisms that died.

In this case the chemistry is basically *be carbon based* which isn't that hard to achieve. So long as it can create 6 carbon rings (benzene rings) and long carbon chains similar to starches and cellulose we should be good to get to coal and oils.

Since we can breath the air and eat the locals [and vice versa] the chemistry is, for this purpose, identical to ours. If the correct conditions occurred the formation of fossil fuel deposits can be taken pretty much for granted.

As you say, local biochemistry could vary a long long way from ours and still produce carbon and hydrocarbon deposits. I can, with a little effort, imagine carbon-based life that might not permit the conditions to occur, but the _story_ wouldn't occur on such a planet - if I'm not mistaken, it would not develop an oxygen atmosphere for one thing.

However, I think the OP was reading 'terraforming' to mean the introduction of life on a previously lifeless planet, which is far from the case here.

Silverwall wrote:In this case the chemistry is basically *be carbon based* which isn't that hard to achieve. So long as it can create 6 carbon rings (benzene rings) and long carbon chains similar to starches and cellulose we should be good to get to coal and oils.

Louis R wrote:Since we can breath the air and eat the locals [and vice versa] the chemistry is, for this purpose, identical to ours. If the correct conditions occurred the formation of fossil fuel deposits can be taken pretty much for granted.

As you say, local biochemistry could vary a long long way from ours and still produce carbon and hydrocarbon deposits. I can, with a little effort, imagine carbon-based life that might not permit the conditions to occur, but the _story_ wouldn't occur on such a planet - if I'm not mistaken, it would not develop an oxygen atmosphere for one thing.

However, I think the OP was reading 'terraforming' to mean the introduction of life on a previously lifeless planet, which is far from the case here.

Silverwall wrote:In this case the chemistry is basically *be carbon based* which isn't that hard to achieve. So long as it can create 6 carbon rings (benzene rings) and long carbon chains similar to starches and cellulose we should be good to get to coal and oils.

IIRC, early on the "terraforming" is mentioned to include quite extensive "Earthworks"
(Including the original canal system)

chrisd wrote:
However, I think the OP was reading 'terraforming' to mean the introduction of life on a previously lifeless planet, which is far from the case here.


IIRC, early on the "terraforming" is mentioned to include quite extensive "Earthworks"
(Including the original canal system)

All valid points. Thanks, all!