Hydraulic Fracturing Design Optimization Guidelines for Heterogeneous Reservoir

Abstract

Abstract This paper describes the journey of hydraulic fracturing design solutions and implementation in Khazzan field. More than 100 wells have been stimulated with hydraulic fracturing in the field in the last decade. Most of these wells were treated with a single-stage massive propped hydraulic fracturing treatment aimed at stimulating the entire vertical productive zone in a single treatment. More recently, hydraulic fracturing has begun on the southern acreage from Khazzan, referred to as Ghazeer. Producing layers in this area are thicker and higher permeability and, as a result, more prolific. Based on the available data and experiences, the establishment of clear guidelines has become a requirement to help the understanding and adjust the hydraulic fracturing design for each well to be become a well-specific optimum design. During the stimulation journey, surveillance techniques have been utilized and implemented in the Khazzan and Ghazeer fields to provide and develop better understanding of the fracture propagation process. These data have proven essential to support stimulation design evolvement and determine if multiple fracturing stages are justified or whether a single stage would be sufficient. Based on a wide range of hydraulic fracture stimulation operations performed across the Khazzan and Ghazeer fields, a flowchart was developed to integrate all the lessons learned from the previous experience and help optimize future fracture design. Clear guidelines include the rationale between the selection of single or multiple fracturing stages, the selection of optimal pad fractions, and other associated details of the fracture design. This flowchart has been extensively validated with surveillance and has proven its inherent value in many stimulated wells, with either single or multiple proppant fracturing stages.