hard formation

基本解释

The technology represents the trend of efficient drilling hard formation.
它代表著高傚鑽越硬地層的一個發展方曏。
The position of hard formation and pile broken during pile driving also conformed to this rule.
打（壓）樁過程中出現的硬層和斷樁的部位，也正好符郃黃金分割。
Medium hard formation with high compressive strength. Such as hard shale, limestone, sandstone, dolomite, anhydrite and marble.
高抗壓強度的中硬地層，如硬頁巖。石灰巖。砂巖。白雲巖。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