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冲击钻井
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Percussion drilling is suitable for unconsolidated and consolidated formations: Sand, silt, stiff clays, sandstone, laterite and gravel layers.冲击钻井适用于下列疏松或固结的构造：沙、淤泥、硬黏土、砂岩、红土和砾石层。
Manual percussion drilling is generally used up to depths of 25 meters.人工冲击钻井通常用于最深为25米的井。
Before drilling starts, it is good to analyse where the water might be. There are lots of clues to look for in WellSpringAfrica.org's [http://www.wellspringafrica.org/WebManual/chapter4.htm Selecting a Site.]钻井开始前，最好先分析水可能在何处。非洲泉源组织的网站（WellSpringAfrica.org）上提供了许多表示有水源的指征线索。[http://www.wellspringafrica.org/WebManual/chapter4.htm 请选择网站。]
