During the test and production of in-situ leaching of sandstone deposit, it is very difficult and complicated to exploit boreholes when confined water head of ore-bearing acquifer is quite low.
在砂岩矿床的地浸试验和生产中，含矿含水层地下水承压水头很低时，地浸钻孔的开拓难度很大且工艺复杂。
2
When the system is confined well, the change of observation water level has a linear relation with water head change.
在系统封闭很好的情况下，观测水位的变化基本与水头的变化呈线性关系。
3
Therefore, further increase of magnetic recording density is largely confined by the writing ability of the magnetic head.