What is an aquifer?

An aquifer is defined as a geological formation that is capable of storing and transmitting water. This means that it consists of permeable materials, such as sand, gravel, or limestone, which allow water to flow through them easily. Aquifers are essential components of the hydrological cycle, serving as natural underground reservoirs that can supply water to wells and springs.

When considering why the other options do not fit the definition of an aquifer, it becomes clear that they describe unrelated concepts. A type of water well that cannot produce water refers to infrastructure rather than a geological formation, and therefore, does not align with the concept of an aquifer. Similarly, a method of drilling into the ground pertains to the techniques of extraction rather than the natural storage of water in geological formations. Lastly, a machine used for extracting oil is focused on a specific type of resource extraction, unrelated to the natural occurrence and behavior of groundwater in aquifers.

In summary, the definition of an aquifer as a geological formation capable of storing and transmitting water is foundational to understanding water supply systems and the importance of sustainable management of groundwater resources.