− | The size of a petroleum system includes the total volume of all recoverable hydrocarbons that originated from a single pod of active source rock. This total volume is used to compare against other [[petroleum systems]] and to determine the generation–accumulation efficiency. | + | The size of a [[petroleum system]] includes the total volume of all recoverable hydrocarbons that originated from a single pod of active [[source rock]]. This total volume is used to compare against other petroleum systems and to determine the generation–accumulation efficiency. |