ABSTRACT
There are three main classifications of geological formations: igneous, sedimentary and metamorphic. Igneous rocks have been created from a molten mass and can be classified into those that cooled slowly deep into the earth and those which underwent a quicker solidification nearer the surface. Whilst igneous rock masses will tend to be hard, there is a degree of weathering. In fact varying degrees—making it softer as it gets nearer the surface. Metamorphosed igneous rocks have another trade-mark in that they can contain a considerable amount of mica, and will tend to shine. By great and careful work, we have made igneous rocks yield sufficient water for a modest pump, but generally don't expect to produce much above hand-pump discharges. In sedimentary formations water can be abundant, as can the drilling problems for the unwary driller. There are four main types in the sedimentary formations: arenaceous, argillaceous, calcareous, and organic.
