Carbonate Rock Typing Using NMR Data: A Case Study from Al Shaheen Field, Offshore Qatar

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractComplex pore size distributions encountered in carbonate rocks have a large impact on the fluid flow characteristics of carbonate reservoirs. Consequently, although nuclear magnetic resonance (NMR) has been frequently used for characterization of clastic reservoirs, it has not been widely applied to carbonates. This paper describes a case study from the Shuaiba carbonate reservoir of the Al Shaheen field, offshore Qatar. Core data from a study well were used to establish an NMR carbonate rock-typing model for permeability estimation. The rock-typing model was verified in the study well with a wireline NMR logging tool. Core analysis included thin-section petrography, NMR surface relaxivity, mercury injection, porosity and permeability measurements. NMR distributions determined on core were partitioned and linked to pore body size and pore throat size distributions. Several rock types were also defined based on their NMR and petrographic characteristics. To improve permeability prediction in the cored interval of the study well, an NMR-based permeability equation was derived. The core-calibrated NMR carbonate rock typing model was applied to noncored sections of horizontal wells drilled in the Shuaiba formation having logging-while-drilling (LWD) NMR data to improve rock typing and permeability estimation, thus, providing valuable input data for reservoir modeling.

Characterizing Facies and Porosity-Permeability Heterogeneity in a Geothermal Carbonate Reservoir with the Use of Nmr-Wireline Logging Data

“…fluid distribution/content and rock-fluid interaction studies within the reservoir adapted to 3D dynamic simulations) (Aliakbardoust and Rahimpour-Bonab, 2013;Ghedan, 2007;Skalinski and Kenter, 2015). In addition, some publications report the use of NMR well-logs for rock-typing through an integrated approach (Frank et al, 2005;Gharechelou et al, 2017Gharechelou et al, , 2015Gonçalves et al, 2017;Vincent et al, 2011). Here we take a simpler approach by defining different rock-types based exclusively on NMR T 2 -distributions (provided via NMR logs) using a clustering method (i.e.…”

Integração do perfil de ressonância magnética nuclear (RMN) com resultados de ensaios de laboratório em reservatórios carbonáticos

“…Mai e Kantzas (2002) verificaram que, além dos cortes serem diferentes dos conhecidos na literatura (100 ms), os modelos de permeabilidade não eram adequados e, por isso, propuseram um novo modelo. Já Frank et al (2005), para melhor ajuste das permeabilidades em carbonatos do Qatar, utilizaram uma distinção entre o conceito de FFI e macroporosidade e aplicaram uma equação de permeabilidade derivada de Timur-Coates. O problema também é verificado em outras litologias com sistemas porosos complexos, com ocorrência de abundante microporosidade, como relata o trabalho de Romero e Gomez (2004) em reservatórios siliciclásticos da Venezuela.…”