Characterization of spatial porosity and mineral distribution of crystalline rock using X-ray micro computed tomography, C-14-PMMA autoradiography and scanning electron microscopy

Show full item record



Permalink

http://hdl.handle.net/10138/323848

Citation

Voutilainen , M , Miettinen , A , Sardini , P , Parkkonen , J , Sammaljärvi , J , Gylling , B , Selroos , J-O , Yli-Kaila , M , Koskinen , L & Siitari-Kauppi , M 2019 , ' Characterization of spatial porosity and mineral distribution of crystalline rock using X-ray micro computed tomography, C-14-PMMA autoradiography and scanning electron microscopy ' , Applied Geochemistry , vol. 101 , pp. 50-61 . https://doi.org/10.1016/j.apgeochem.2018.12.024

Title: Characterization of spatial porosity and mineral distribution of crystalline rock using X-ray micro computed tomography, C-14-PMMA autoradiography and scanning electron microscopy
Author: Voutilainen, Mikko; Miettinen, Arttu; Sardini, Paul; Parkkonen, Joni; Sammaljärvi, Juuso; Gylling, Björn; Selroos, Jan-Olof; Yli-Kaila, Maarit; Koskinen, Lasse; Siitari-Kauppi, Marja
Contributor: University of Helsinki, Geological disposal of spent nuclear fuel
University of Helsinki, Geological disposal of spent nuclear fuel
University of Helsinki, Department of Chemistry
Date: 2019-02
Language: eng
Number of pages: 12
Belongs to series: Applied Geochemistry
ISSN: 0883-2927
URI: http://hdl.handle.net/10138/323848
Abstract: The spatial porosity and mineral distribution of geological materials strongly affects transport processes in them. X-ray micro computed tomography (X-mu CT) has proven to be a powerful tool for characterizing the spatial mineral distribution of geological samples in 3-D. However, limitations in resolution prevent an accurate characterization of pore space especially for tight crystalline rock samples and 2-D methods such as C-14-polymethylmethacrylate (C-14-PMMA) autoradiography and scanning electron microscopy (SEM) are needed. The spatial porosity and mineral distributions of tight crystalline rock samples from Aspo, Sweden, and Olkiluoto, Finland, were studied here. The X-mu CT were used to characterize the spatial distribution of the main minerals in 3-D. Total porosities, fracture porosities, fracture densities and porosity distributions of the samples were determined using the C-14-PMMA autoradiography and characterization of mineral-specific porosities were assisted using chemical staining of rock surfaces. SEM and energy dispersive X-ray spectroscopy (EDS) were used to determine pore apertures and identify the minerals. It was shown that combination of the different imaging techniques creates a powerful tool for the structural characterization of crystalline rock samples. The combination of the results from different methods allowed the construction of spatial porosity, mineral and mineral grain distributions of the samples in 3-D. These spatial distributions enable reactive transport modeling using a more realistic representation of the heterogeneous structure of samples. Furthermore, the realism of the spatial distributions were increased by determinig the densities and porosities of fractures and by the virtual construction heterogeneous mineral distributions of minerals that cannot be separated by X-mu CT.
Subject: C-14-PMMA autoradiography
CONNECTED POROSITY
Crystalline rock
Crystalline rocks
DIFFUSION EXPERIMENT
Energy dispersive X-ray spectroscopy
FRACTURES
Heterogeneity
IMPREGNATION
INTERFACE
MICROTOMOGRAPHY
OLKILUOTO
Pore structure
Porosity
RESOLUTION
SCALE
SIMULATION APPROACH
Scanning electron microscopy
X-ray micro computed tomography
116 Chemical sciences
1171 Geosciences
Rights:


Files in this item

Total number of downloads: Loading...

Files Size Format View
Appl_GeoChem_subtitted.docx 10.26Mb Microsoft Word View/Open

This item appears in the following Collection(s)

Show full item record