Development of an Integrated Reservoir-Surveillance Process
Authors: Denney Dennis 
Published: February 2015

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper SPE 120229, "Development of an Integrated Reservoir-Surveillance Process for World's Second-Largest Field in Kuwait," by Sameer F. Desai, SPE, Hussain Z. Al-Ajmi, SPE, and Jamal H. Al-Humoud, Kuwait Oil Company, and Naz H. Gazi, SPE, Halliburton, prepared for the 2009 SPE Middle East Oil & Gas Show and Conference, Kingdom of Bahrain, 15-18 March. The paper has not been peer reviewed.

The Greater Burgan field in Kuwait was discovered in 1938 and contains more than 1,000 wells. It is extremely important to identify and perform focused surveillance work to have a better understanding of the reservoir drainage mechanism, remaining potential, and pressure decline. Considerable data accumulate every year, leading to questions about whether acquiring so much data is justified. This paper describes the approach to develop an integrated reservoir-surveillance plan for monitoring the field.

Introduction

The Greater Burgan sandstone oil field covers a surface area of approximately 320 sq miles. The four main reservoir units are the Wara, Mauddud, Burgan Third sand, and Burgan Fourth sand. Other contributing units are Minagish, Marrat, and Zubair reservoirs. A very dynamic development plan was implemented to sustain production. The strategy involves increased well activity and production-facility and -capacity upgrade. Many new wells are planned, including high-producing-rate horizontal wells in the main Burgan sands.

Reservoir surveillance is key. With new wells being drilled, the need for organized surveillance has increased to monitor this large reservoir, depletion trends, remaining potential, and pressure support. Surveillance planning is critical in ensuring that sufficient data are acquired. Standard processes must be in place to manage and interpret the acquired data. The quality and value of information must be assessed to justify the surveillance plan and the future requirements for continued optimization of current production and reservoir-management strategies.

Current Process

Routine surveillance data are acquired annually to optimize well production and to provide input for reservoir-management studies. Surveillance activities were reviewed over the last 3 years to assess the need for and to highlight the interpretation of the acquired data, and to determine the consequent value-added decisions based on the analysis. Surveillance data add value through incremental benefits in terms of production gain or water curtailment, and by incorporating data into ongoing reservoir-management and -mapping studies.

Focusing on a New Approach The approach focuses on value generated from the acquired-data interpretation to provide reservoir pressure; reservoir permeability; water saturation; sweep efficiency; well-productivity index; well flow capacity; fluid contacts; and flow rates of oil, gas, and water. The significance of surveillance information through routine and planned diagnostic and monitoring purposes is measured against an ultimate gain in production, water curtailment, production optimization, and overall meeting of best reservoir-management practices. Timely update of information, through surveillance, on the water-encroachment maps and in simulation studies is instrumental for optimizing recovery and formulating a better depletion strategy.