The definition of an aquifier can be given as a layer of water that is found underground, and the layer contains some rocks that are easily permeable. The layer can also contain some permeable materials such as gravel, sand or silt. Such materials are considered important for the purposes of extraction of the water from underground using water wells (Ralph, 1989).
When examining the geology of a certain region, one of the characteristics that one would most likely consider is getting an area that has a lot of gravel deposits. Gravel as is already mentioned is a permeable rock that easily allows water to pass through it so that the extraction process becomes easy. Apart from the gravel, one needs to consider the bedrock geology of that place so as to be able to know how deep water runs in that particular region (Willard, 1988). The depth of the water determines how deep the holes can get drilled in order to get to the water level for purposes of drilling.
The other characteristics that should be put into consideration is the level of the unconsolidated materials. If the materials mentioned are found at a shallow level then that would mean that very little water can be found at that place. On the flipside, if the materials are deep within the ground then that means that region can produce a lot of water.
In taking into account the human factors, areas such as those with low level of bedrock should always be avoided since such areas may be very risky to conduct drilling. The land in such areas can easily subside thereby causing deaths (Fletcher, 1987). Other areas include regions where sand and gravel form the actual layer of the earth. Finally, areas with sloping bedrock should also be avoided at all costs.