Assessment of microporosity in carbonate reservoirs using Digital Rock Physics (DRP) and other conventional techniques

Abstract

Microporosity is a key parameter to estimate the total porosity system in carbonate reservoirs, and its impact is significant in reservoir characterization, such as defining the accurate original distribution of hydrocarbons in place (STOIP) and the relationship between permeability and total porosity, which in turn defines Petrophysical Groups (PG's) and Reservoir Rock Types (RRT's). It also impacts acoustic/ elastic properties of both shear-wave velocity (Vs) and compressional-wave velocity (Vp), resistivity logs in reading the water saturation in reservoirs with microporosity, known by 'Low Resistivity Pay Zones', and also in the segmentation process when conducting Digital Rock Physics (DRP) calculations. The microporosity is playing a big role in defining the threshold between grains and pores to build the 3D solid matrix or the 3D pore network. Therefore, the main driver for this thesis is to quantify the microporosity in carbonate reservoirs. The DRP based micro-porosity will be rigorously examined and quantified, and compared with established conventional techniques, such as Mercury Injection Capillary Pressure (MICP), Nuclear Magnetic Resonance (NMR), Thin Section (TS) and Scanning Electron Microscopy (SEM). Three distinct RRTs are chosen for the evaluation and comparison. The current investigations established the most reliable cut-off for microporosity in carbonate reservoirs and, accordingly, limitations and errors associated with different conventional techniques.

Date of Award	Dec 2013
Original language	American English
Supervisor	Jorge Salgado Gomes (Supervisor)