Combining Continuous Fluid Typing, Wireline Formation Testers, and Geochemical Measurements for an Improved Understanding of Reservoir Architecture

Abstract

Summary Identifying compartmentalization and understanding reservoir structure are of critical importance to reservoir development. Traditional methods of identifying reservoir compartmentalization, such as drillstem tests and extended well tests, often become impractical in deepwater settings, with costs approaching the costs of new wells and emissions becoming increasingly undesirable. Thus, compartments often have to be identified by some other means. Individual formation-pressure measurements, downhole fluid analysis (DFA), and geochemistry are known to provide important information about reservoir architecture. When these powerful methods are combined systematically and applied to data sets, the resulting synergy delivers a much more accurate and robust picture of the reservoir. In this paper, we review a number of case studies in which we have successfully combined continuous fluid/facies mapping, pressure-gradient measurements, DFA, and geochemistry for a reservoir-continuity assessment in a diverse range of geological settings, including a wide range of field sizes, structural environments, reservoir lithologies, and oil types. Particular emphasis is placed on comparing the strengths and limitations of the different techniques in revealing reservoir architecture, especially vertical-permeability barriers. We present a number of unambiguous cases, for which multiple data streams might be viewed as being somewhat redundant. More-ambiguous cases, in which the multiple data streams are required to make a robust assessment of key reservoir properties, are also presented.

Determining static reservoir connectivity using noble gases

“…Many methods have been developed to assess the connectivity of a reservoir prior to production (e.g. Jolley et al, 2010 and papers within;Elshahawi et al, 2008) but only rarely can all potential scenarios be fully resolved. Furthermore, it is currently particularly difficult to assess the connectivity between fluids of different phases.…”

In Situ Methane Determination in Petroleum at High Temperatures and High Pressures with Multivariate Optical Computing

“…Accurate compositional measurements of reservoir petroleum fluids are necessary for petroleum exploration and production activities. These activities include ensuring a well is drilled safely, identifying new discoveries, evaluating the production potential and value of such discoveries, optimizing the capital investment for production, and designing a field management system across multiple wells. − To determine the petroleum fluid composition in a newly drilled well, samples are typically acquired from within it at high temperature and pressure using a wireline formation tester (WFT). − The WFT is lowered into the well on an electrical cable and captures fluid samples in pressurized sample chambers.…”