hard formation

常见例句

The technology represents the trend of efficient drilling hard formation.
它代表着高效钻越硬地层的一个发展方向。
The position of hard formation and pile broken during pile driving also conformed to this rule.
打（压）桩过程中出现的硬层和断桩的部位，也正好符合黄金分割。
Medium hard formation with high compressive strength. Such as hard shale, limestone, sandstone, dolomite, anhydrite and marble.
高抗压强度的中硬地层，如硬页岩。石灰岩。砂岩。白云岩。和硬石膏。大理石。

Chevron, for example, has invested heavily in shale production in the Marcellus field in Pennsylvania, while ConocoPhillips has been working hard at the Eagle Ford formation in Texas.
FORBES: The Shale Scramble: Exxon Buying Bakken Assets For $1.6B From Denbury
In particular, taxes should not: discourage hard work and risk taking, impede capital formation, impose high costs for computation and enforcement, favor particular groups or activities, or intrude on individual liberty any more than is absolutely necessary.
FORBES: Spending Is Choking Us And Tax Cuts Are No Heimlich Maneuver
Another is to alter the voting system in a way that avoids the formation of coalitions, which have found it so hard to be decisive.
ECONOMIST: Action man