An Integrated Downhole Production Logging Suite for Locating Water Sources in Oil Production Wells

Abstract

Understanding of fluid movement in and near the wellbore is a crucial factor for effective reservoir management including successful remedial actions and field development planning. One of the key objectives in well surveys is to detect and locate sources of fluid flows behind multiple pipe barriers. The conventional Production Logging Tool (PLT) is run to detect fluid flow and identify the type of fluid under downhole conditions, but is limited to measurements only inside the wellbore. Similarly, other diagnostic techniques, such as cement bond logging, give insight only into the cement integrity and also have limited capabilities to detect cross flows behind casing.Recent developments in temperature and noise logging tools and advanced interpretation techniques have provided higher resolution and sensitivity, enabling the detection of previously undetectable leaks and fluid flow behind casing [1].In the present case, a water zone has been identified in a producing formation with High Precision Temperature (HPT) logging and Spectral Noise Logging (SNL) followed by advanced numerical temperature modelling using the TermoSim software application. SNL identifies flowing zones and differentiates between rock-matrix and fracture flows, and TermoSim then numerically models heat exchange between the wellbore fluid and the surrounding rocks and reservoirs. The resulting model quantifies fluid production from each reservoir unit. Conventional production logging (PLT) locates fluid entry points in the wellbore. The integrated HPT-SNL and PLT logging suite can trace the entire water path from the reservoir into the wellbore. This paper describes water source identification by an HPT-SNL-PLT logging suite deployed in several production wells of a Kuwait oil field. In some of the wells in this field, it has been found that water encroached into the perforations from a watered reservoir below through a channel behind the casing. In other wells, it has been found that cold water breakthrough occurred laterally from nearby water injectors. The exact identification of water sources is a crucial step in any further well remedial work to reduce or eliminate them from oil producing wells. [2]

A Review of Chan Plot Application and Recent Advanced Models for Diagnosing Excessive Water Production

“…Various criteria have been used in the literature to classify water production problems, depending on the authors' interests and the specific focus of their work. They have been categorized based on their complexity and the ease of implementing shut-off treatments, ranging from simple to complex solutions (Bailey et al, 2000;Seright et al, 2003).…”

“…A common approach to mitigate coning in the early stages involves controlling the critical coning rate. This rate represents the maximum amount of oil that can be produced without forming a cone and is often economically challenging to achieve (Bailey et al, 2000).…”

“…This challenge manifests in reduced income, diminished production levels, and escalating costs associated with upgrading water treatment facilities and disposal systems (Rabiei et al, 2009). The expenses incurred in this process vary from 5 to more than 50 cents per water barrel (Dahl et al, 1992), and they soar even higher, reaching $4 for every barrel of oil, when dealing with wells producing an 80% water cut (Bailey et al, 2000). Moreover, recent studies estimated produced water treatment and disposal costs ranging from $5 to $100 per cubic meter depending on the process and region (Zolfaghari et al, 2022).…”

“…To mitigate the risk of water-related issues, the sources of unwanted water should be accurately diagnosed. Traditional diagnostic techniques, such as well logs, production logging, and pressure transient analysis (PTA), have been used (Bhagavatula et al, 2015;Wang et al, 2023;…”

Diagnosis of Water-Influx Locations of Horizontal Well Subject to Bottom-Water Drive through Well-Testing Analysis

“…Aibazarov et al [20] described how to determine the downhole fluid flow path and further to optimize water shut-off operations by using integrating data from spectral noise logging tools and multisensor production logging. Over the past few years, many researchers pinpointed water entry intervals through production logging [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36]. On the other hand, another monitoring system can provide vital data (e.g., pressure and temperature) for waterinflux detection.…”