TY - JOUR

T1 - Description of chalk microporosity via automated mathematical morphology on scanning electron microphotographs

AU - Meyer, Aurelien G.

AU - Nourani, Meysam

AU - Stemmerik, Lars

N1 - Funding Information:
This project was funded by the Centre for Oil and Gas/Danish Hydrocarbon Research and Technology Centre (DHRTC).
Publisher Copyright:
© 2019 The Author(s).

PY - 2020/8

Y1 - 2020/8

N2 - The spatial geometry of microporosity influences fluid flow through chalk reservoirs and aquifers, and, hence, numerous geological processes. Analysing porosity is thus often critical in geological studies. Techniques such as mercury injection capillary pressure (MICP), nuclear magnetic resonance (NMR) and X-ray computed tomography (CT) are expensive, and hence often inapplicable to many geological studies, which often necessitate the analysis of large numbers (hundreds) of samples. However, scanning electron microscopes (SEM) have become widely available, and SEM imagery analysis, therefore, is cheaper and faster. However, extracting meaningful porosity descriptors from SEM images can be difficult, in part because of the difficulty in digitally separating pores in laterally continuous pore networks. Moreover, mathematical morphology can be automated to collect porosity parameters from hundreds of images in a short time frame. The technique also quantifies the shape complexity of porosity. Considering the influence of pore geometry on fluid flow, the capacity of image analysis to deconstruct the pore network by pore shapes is crucial when building flow models. This study concludes that mathematical morphology constitutes an alternative to other techniques in geological studies of microporosity. Lithologies dominated by micro- and nanoporosity, such as shales and tight sandstones, could also benefit from this technique.

AB - The spatial geometry of microporosity influences fluid flow through chalk reservoirs and aquifers, and, hence, numerous geological processes. Analysing porosity is thus often critical in geological studies. Techniques such as mercury injection capillary pressure (MICP), nuclear magnetic resonance (NMR) and X-ray computed tomography (CT) are expensive, and hence often inapplicable to many geological studies, which often necessitate the analysis of large numbers (hundreds) of samples. However, scanning electron microscopes (SEM) have become widely available, and SEM imagery analysis, therefore, is cheaper and faster. However, extracting meaningful porosity descriptors from SEM images can be difficult, in part because of the difficulty in digitally separating pores in laterally continuous pore networks. Moreover, mathematical morphology can be automated to collect porosity parameters from hundreds of images in a short time frame. The technique also quantifies the shape complexity of porosity. Considering the influence of pore geometry on fluid flow, the capacity of image analysis to deconstruct the pore network by pore shapes is crucial when building flow models. This study concludes that mathematical morphology constitutes an alternative to other techniques in geological studies of microporosity. Lithologies dominated by micro- and nanoporosity, such as shales and tight sandstones, could also benefit from this technique.

UR - http://www.scopus.com/inward/record.url?scp=85089223528&partnerID=8YFLogxK

U2 - 10.1144/petgeo2019-018

DO - 10.1144/petgeo2019-018

M3 - Article

AN - SCOPUS:85089223528

SN - 1354-0793

VL - 26

SP - 386

EP - 399

JO - Petroleum Geoscience

JF - Petroleum Geoscience

IS - 3

ER -