The generation of hydrocarbons of the Ordovician source is different from that of Mesozoic nd Cenozoic sources since there were on high plants in the Ordovician Period.

• 由于当时没有高等植物出现，因此奥陶系烃源岩在油气生成上与我国东部中、新生界陆相烃源岩有着明显的不同。