They were connecting up the story of underground activity which is America-wide.

他们连接了地下活动的故事，这是美国范围内。

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Carrying out the cost calculation of underground activity not only needs to set up and perfect the inner management system but also needs information system to back it up.

实施井下作业成本核算不仅需要建立和完善内部管理制度，还要有必要的信息系统予以支撑。

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The latter two sources are limited to those few areas where surface water seeps down through underground faults or fractures to reach deep rocks heated by the recent activity of molten rock material.

后两种来源局限于少数区域，在这些区域，地表水通过地下断层或断裂往下渗透，从而接触到被近期的熔岩活动加热的深层岩石。

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The criteria considered include population density, the distance to underground geological formations suitable for carbon sequestration, seismic activity, terrain, proximity to airports, military bases and so on and so forth.

FORBES: Plotting The Next-Generation U.S. Power Grid