Numerical Approach in Analyzing Pressure Transient Responses in Dual-Porosity Dual-Permeability DPDP Reservoirs

Abstract

Advancements in numerical well testing packages in interpreting pressure transient behavior of complex well geometries and reservoir structures have lead to an improved understanding of the multi-scale heterogeneity encountered in dual-porosity dual-permeability (DPDP) reservoirs. This paper demonstrates the power of numerical well testing models in handling conceptual cases of increasing complexity in dual-porosity dual-permeability (DPDP) reservoirs where a high permeability matrix system interact with super-k intervals, fractures, and faults systems with different levels of complexity. Numerical well test models are built using data from multiple scales and sources (image logs, flowmeter responses (PLTs), petrophysical logs (FALs), and seismic attributes) to match pressure transient responses of wells completed in dual-porosity dual-permeability reservoirs. Six generalized conceptual cases are presented in this paper; a vertical power water injector that initiated induced fractures due to injection above fracture pressure, a vertical well near an area of intersecting faults, a 40-degree deviated well intersecting diffuse fracture network, a deviated well near a conductive fracture corridor, a horizontal well intersecting a finite conductivity fracture, and a horizontal well intersecting an infinite conductivity fracture. An integrated approach was used to match the pressure responses in all cases. Experience shows that the most representative well test solution comes from a thorough integration of well-test data with all available static and dynamic data (e.g. image logs, flowmeter responses (PLTs), geophysical, and petro-physical data). In addition, inclusion of pressure transient responses of offset wells in the area understudy as part of the analysis is crucial in choosing the most representative well test model. In summary, this paper provides guidance and best practice to reservoir engineers in building numerical well test models to analyze fracture and matrix responses in dual-porosity dual-permeability (DPDP) reservoirs. Conceptual cases emphasize integration of multiple sources of static and dynamic data to model different well responses.

Numerical Well Test Analysis of Condensate Dropout Effects in Dual-Permeability Model of Naturally Fractured Gas Condensate Reservoirs: Case Studies in the South of Iran

“…e only difference is that, in all cases, the matrix can also produce into the well [21]. Many researches have been conducted on naturally fractured reservoirs applying the dual-porosity and dual-permeability model [36,[38][39][40][41][42][43][44][45][46][47][48][49][50][51].…”