Abstract: In a fluid flood process for enhancing the secondary recovery of hydrocarbons from a hydrocarbon permeable and hydrocarbon bearing reservoir using plural recovery wells, each adjacent at least one injection well. Each well has a well bore. A horizontal injection fracture extends substantially horizontally from the well bore of each of selected injection well bores. A horizontal recovery fracture extends substantially horizontally from the well bore of each of selected recovery wells and is vertically displaced from and overlapping with one or more of the injection fractures of the adjacent injection wells. A pair of overlapping injection and recovery fractures, that would overlap with a low permeable layer in the reservoir, is selectively positioned vertically at one side of such layer in the reservoir.

Abstract: A process for enhanced recovery of hydrocarbons, such as oil from a geological reservoir through an injection well bore and a plurality of production well bores which extend into the geological reservoir. Flooding is performed through at least one injection well bore into a lower portion of the geological reservoir, to thereby form a substantially horizontal injection fracture which may have an upward vertical component. The vertical component is elongated along an azimuth. The vertical components of any significance size are not always formed on horizontal fractures. However, to avoid intersecting horizontal production fractures into the vertical components, certain procedures must be followed. To this end, the azimuth of the elongation of the vertical component is determined. The producing well bores are then disposed, substantially parallel with the azimuth of the elongation of the vertical component and along a line displaced from the injection well bore.