OPTIMIZATION OF THE DESIGN OF TRANSVERSE HYDRAULIC FRACTURES IN HORIZONTAL WELLS PLACED IN DUAL POROSITY TIGHT GAS RESERVOIRS

Open Access
Author:
Gorucu, Seyhan Emre
Graduate Program:
Petroleum and Mineral Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
None
Committee Members:
  • Turgay Ertekin, Thesis Advisor
Keywords:
  • Horizontal Wells
  • Tight Gas
  • Dual Porosity
  • ANN
  • Transverse Fractures
Abstract:
The exploitation of the gas from tight gas reservoirs has been increasing due to the advances in unconventional gas technologies and depletion of conventional gas resources. Drilling horizontal wells and using hydraulic fractures are needed to produce economically viable amounts from tight sands. In this research, optimization of a hydraulically fractured horizontal well placed in naturally fractured tight gas sand reservoir systems was studied. A commercial reservoir simulator coupled with artificial neural network (ANN) in order to create an expert system that can be used to design an efficient stimulation strategy. Reservoir simulation was used in order to generate production profiles of the reservoir system which was, then, used to train the artificial neural network system. The ANN developed in the project consists of two parts: forward and inverse processes. In the forward process, an input data set which includes well and completion design parameters and reservoir properties are used to create an ANN toolbox in order to predict the production profile. In the inverse process, several design parameters and the desired production profiles were introduced as the input data in order to create an ANN toolbox to estimate the optimum design parameters. It is found that in both expert systems, functional links play a significant role in the success of the ANN tool. The results estimated by this developed toolbox can be used as preliminary information about the production profiles or the required wellbore and fracture design parameters for different cases. This study showed that natural fracture permeability is the principal factor that determines the magnitude of the production. For this reason, the ANN toolbox is sensitive to a larger range of natural fracture permeability. In addition, conductivity of the natural fractures and the hydraulic fractures are important factors affecting production.