which of the following processes transforms oil-saturated sandstones into tar sands?

The process that transforms oil-saturated sandstones into tar sands is known as „bitumen maturation.“ This occurs when the original oil undergoes thermal and chemical changes due to geological heat and pressure over time, leading to the formation of a thicker, viscous substance called bitumen. This bitumen is what characterizes tar sands, making them a significant source of unconventional oil.