There are two oil and natural gas accumulation characters in basement rock reservoir which are all extraneous source of oil and porous fractured reservoir.

基岩潜山油藏具有油气成藏的两种特征，即外来的油源和裂缝性储集空间。

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The appeal hearing was told it was "just as likely" that the particle came from "some extraneous source as it was that it came from a gun fired".

BBC: George not guilty of Dando murder