Because of climatic changes and new tectonic movements, several sea and land evolutions occurred in the Bohai sea area to result in the formation of subsurface brine.

由于气候变化和新构造运动，渤海曾发生多次海陆演化，从而形成了第四纪地下卤水。

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Through further analyzing the conditions of subsurface blowhole formation and optimizing the technology conditions, the subsurface blowhole defect was eliminated.

进一步分析球墨铸铁活塞环皮下气孔的形成条件，通过优化主要工艺参数，达到防止皮下气孔的出现。

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It isolates and segregates different subsurface zones and rock units, it controls corrosion, and it stabilizes the well, the pipe and the rock formation itself.

FORBES: The Fracking Solution Is A Good Cement Job