Definition - What does Zone mean?
A zone can be defined as a gap or a component of a rock that is separated from its surrounding rock formations. This separation is usually based on geological reasons such as natural fractures, faults or fossils. Every zone is categorized based on this feature. For example, a zone that contains fossils is known as a biostratigraphic zone, whereas a zone with lots of fractures is referred to as a fracture zone.
Petropedia explains Zone
In geology, a zone is generally referred to as an area or a stretch of land that bears particular individualities. When a rock formation is distinctively different from its surrounding rocky area based on a particular set of features, it is called a zone. In the oil and gas industry, zones are labeled to different areas that are based on geological aspects such as fractures, fossils or faults. When a wellbore is induced with lots of fractures to the inner rock arrangement, it is referred to as a fracture zone, where one can find several of fissures that are connected to one main crack tip.