Oil field water is divided into stratal, head and technical. Stratal headwater, relatively to oil-bearing strata, is divided into edgewater, bottom, intermediate – upper and lower, as well as tectonic fractures water (Fig. 1):
Edge stratal water occupies lower parts of the formation and prop up oil pool on the internal and external contours, which form a ring shape in the plan.
Bottom water prop formation over its entire area, including the crest of reservoir, forming continuous mirror of OWC or GOC.
Intermediate waters lie within oil reservoir, or between the layers that are combined into a single production facility.
The upper and lower waters confined to pure aquifers, regardless of productive pools, and occur above or below the latter. Tectonic fractures water circulate at the fault plane from high-pressure (usually more deep-seated) to low pressure zones. They are able to irrigate head portion of reservoirs, displacing oil from the crest of reservoir to a peripheral zones.