Hydraulic fracturing is a widely used technology in the industry to enhance oil and gas production, particularly in tight formations. Tight gas and shale cannot sustain commercial production rates without fracturing. Although the technique has been used in the industry for many years and vast improvements have been made in upgrading fluid chemistry, proppant types, pump schedule sequence, and overall well completion system, a close evaluation is always required to ascertain that the fracturing has provided the level of productivity expected from the candidate well. Such evaluation and analysis will help improve and optimize the stimulation technique for any given reservoir and field conditions, address specific challenges in that area, and determine remedial plans on any well that did not show expected results in terms of productivity enhancement.

Saudi Arabian gas wells are usually stimulated to enhance and sustain production. Wells drilled in the R-1 reservoir in Field-A, that exhibit low to moderate permeability, are routinely hydraulically fractured. Many of these wells produce a high, sustained rate after a successful stimulation treatment. Some others do not perform up to expectation as seen from the rate decline. This can be caused mainly by inefficient fracture treatments such as achieving short half-length, limited vertical coverage, and poor post-frac cleanup. A critical and intense work on numerous wells has been performed using available data from geology, open hole logs, cores, pressure transient tests, etc., to understand and quantify reservoir characteristics, fracture properties, and flow capacity of these wells to come up with plans to improve productivity. Such plans include remedial treatments such as refracturing, placing additional perforations in previous unperforated intervals, initiating hydraulic fractures in different layers, and sidetracking the well to change its trajectory and geometry to contact new producing intervals. This paper summarizes the well conditions, complete evaluation processes, and suggests remedial procedures for each well to ensure full potential.

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