硬地层 meaning in English

hard layer

Pdc cutters improve drilling in harsh environ - ments translated
钻头在硬地层中的钻井性能
Abstract : being aimed at the poor rock - breaking efficiency of rotary water jet in hard formations and deep wells with radial horizontal well technology , by use of powerful advantages of abrasive jet rock - breaking , experimental study on rotary abrasive jet was made
文摘:针对径向水平井钻井技术中旋转水射流在硬地层和深井中破岩能力低的不足，利用磨料射流破岩能力强的优势，对旋转磨料射流进行了试验研究。
In hard strata with high matrix resistivities , it was considered that the difference between fort - nation resistivity and tight surrounding rock resistivity was caused by fractures except these factors as shaliness , pores , high salinity formation water and the other minerals
在基岩电阻率较高的硬地层中，在去除了泥质、孔隙、高矿化度地层水和其他矿物等影响因素后，地层电阻率与致密围岩电阻率的差异就被认为是裂缝因素引起的。