Peripheral oilfields are also the main direction to increase recoverable reserves, but 90% reserves are located in ultra-low abundance, ultra-low permeability and complex fault-block reservoirs.
外围油田也是增加可采储量的主要方向，但90%的储量位于特低丰度、特低渗透及复杂断块油藏。
2
Fault diagnosis of PLC control system includes fault diagnosis of peripheral equipment, hardware and software of system.