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oil

water
water
Figure 2.2 – Elastic-water drive

When disclosure well oil reservoir under the action of
elastic expansion will initially sail up the hole with sites located in
very close proximity to the hole. But because of the oil from these
sites arrives into the well, the pressure in them decreases, which in
turn causes the inflow of oil from more remote areas. This process
will evolve over time, and at some point, the pressure begins to fall
in the aquifer of the reservoir. Since then, the water from the
aquifer region will begin to enter the reservoir area previously
occupied by water and displace the oil towards the well.
Solution gas drive (or dissolved gas drive). Occurs
when the reservoir pressure is less saturation pressure and gas
bubbles released from the oil at lower pressure expands, to
displace oil wells (in the reservoir moves carbonated oil). Solution
drive found in deposits, which initially oil saturated gas. Due to the
high mobility of the gas efficiency solution gas drive is small.
Solution gas drives are found in saturated reservoirs, in which the
initial pore pressure is above the bubblepoint (Fig. 2.3).
In a solution gas drive lighter hydrocarbon components
that exist as a liquid in the reservoir before it is produced come out
in the form of gas as the reservoir produced. The dissolved gas
coming out of the oil expands. In solution gas drive reservoir
pressure declines rapidly and continuously and wells generally
require pumping or some other artificial lift at an early stage. The

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