The expansion of horizontal well technology over the last twenty years has led to the parallel increase of the number of hydraulic fracturing treatments in highly deviated wells.

The non colinearity of the wellbore axis and of the fracture plane has initially induced significant tortuosity effects and premature proppant screenouts. The length of the perforated interval has therefore been reduced to the acceptable minimum.

Although operational problems have been solved this way, the net pressure response while successfully fracturing did not obey any of the existing 2D models (PKN, KGD or Radial). As a consequence, job designs remained impossible and optimum pumping schedules were typically established by trial and error within a given reservoir.

The present paper offers the required equations to correctly design transverse fracturing treatments, or collinear fractures with short perforation intervals. As compared to previous models, it only replaces the line source and linear flow assumptions (a consequence of colinearity and long perforated intervals) by the point source and radial flow ones. The new model therefore combines both radial fracture and flow geometries, instead of the conventional Radial model where linear flow (orthogonal to the wellbore axis) is assumed.

The theoretical diagnostic (Nolte) plot is in perfect agreement with actual job responses, i.e. a positive, however extremely low slope (almost constant net pressure all along the pad stage). Such a behaviour cannot be interpreted with the responses of the previous models (steep slopes, either positive – PKN – or negative – KGD and Radial).

An actual, well documented treatment in the North Sea validates the proposed model for a short point source hydraulic fracturing from a horizontal wellbore.

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