When drilling in frozen rock, the temperature in borehole is one of the main factors influencing drilling technology.

钻孔温度特性是影响多年冻结岩石钻进工艺的主要因素之一。

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Air drilling is a kind of under-balanced drilling technology with air, whose rock breaking form is different from conventional mud drilling.

空气钻井技术是以空气作为循环介质的欠平衡钻井技术，其钻头的破岩形式与常规泥浆钻井有很大的区别。

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The rotary percussion drilling technology have the advantage to raise the hard rock well drilling speed effectively, prevent the borehole deviation in the hard rock or the complicated geologic strata.

旋转冲击钻井技术依靠冲击器产生冲击载荷并作用在钻头上来破碎岩石。该技术能够有效提高硬地层钻井速度，能够防止硬地层及复杂地层钻井中的井斜问题。

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Fracking is a vital contributor to the recent renaissance in the U.S. oil and natural gas supply picture, as it is the technology, along with horizontal drilling, that makes producing oil and natural gas from very tight shale rock formations possible.

FORBES: Stubbed Toe? Blame Global Warming...or Fracking