There are enough drill sites that have proved it many times over.
But your perfectly welcome to think dinosaurs (500 billion per saudi oil field) fell into a 10 mile deep holes that then closed up and turned into oil, even though petroleum has no biological markers whatsoever. I guess they all just magically vanished from some mysterious process. And why not, anything can happen if you give it a billions of years. And you would be in the majority who believe that baseless 200 year old theory. Or you can enlighten yourself and discover the truth.
There is no Easter Bunny, no Santa Claus and no Abiotic oil.
Every crude oil field has biotic markers and is sourced from sedimentary rock.
The Petroleum System Paradigm and the Biogenic Origin of Oil and Gas
http://www.searchanddiscovery.net/documents/abstracts/2005research_calgary/abstracts/extended/dow/dow.htm
We collected 184 oil samples from 107 fields and all of the productive reservoir rocks in the basin and analyzed them...
...understand where these compositionally different oils came from, we analyzed core samples from all of the organic-rich, non-reservoir rocks in the basin with the same techniques used to study the oils. Each oil group matched to and was closely associated with a different organic-rich interval...