So, A bit of a long winded explanation:
I am designing a world that is meant to be both nostalgic and alien; A world that is familiar enough at first glance, but has many differences to ours.
One difference I thought of is a difference in steam locomotives; in our world, steam locomotives were mostly built cab-backwards, as it is exceptionally difficult to shovel coal into the firebox of a cab-forwards locomotive. The few cab-forwards locomotives that were built were mostly oil burners, as oil can be pumped in from a rear tender without the use of a shovel.
For this to represent the majority of locomotives, I figure oil would have to be the main source of fuel during the industrial age, rather than coal.
Over the previous 500 million years, what environmental conditions would result in crude oil being generally easier to access than coal?
Or, if there is an easier way to justify cab-forwards steam locomotives dominating the rails during the age of steam, what is it?
And, also, what other differences in the world and society would result from the changes required to make this happen?