14-17 May 2018
New Orleans
US/Central timezone

Precipitation and dissolution of cement minerals in sandstone: Opportunities and limitations of pore and plug scale flow analysis for reactive transport modelling approaches

15 May 2018, 14:55
15m
New Orleans

New Orleans

Oral 20 Minutes MS 1.27: Pore Scale Processes and Upscaling of Flow and (Reactive) Transport in Porous Media Parallel 5-H

Speaker

Cornelius Fischer (HZDR)

Description

Reservoir properties of sandstones are controlled by precipitation and dissolution reactions at the pore walls. Both, the formation and dissolution of cement minerals are responsible for the complex pattern formation of porosity and permeability in reservoir rocks.
At the scale of drilled core sections (plugs), experimental and analytical approaches utilize positron emission tomography (PET) with radiotracers (Kulenkampff et al. 2016). Resulting spatiotemporal concentration distributions provide quantitative insight into fluid flow and diffusion parameters. The sensitivity is in the picomolar range of the utilized radiotracers and the spatial resolution is about 1 mm. Thus, mechanistically-important surface features such as etch pits or growth hillocks and their evolution during reaction are not yet part of the direct analysis of the flow field.
Here, we present an approach based on existing information about the complex crystal surface morphology and rate evolution (Fischer& Luttge 2017). We utilize artificial materials that are produced by 3D printing capabilities. Such an approach using PET analysis of sequences of machined surfaces in flow-through experiments provides quantitative insight into the local stability vs. temporal heterogeneity of fluid flow close to reacting surfaces. The measured flow velocity data from PET are implemented into reactive transport models and compared to calculations focusing on small-scale surface reactivity. We discuss the resulting size and complexity of surface rate patterns.

References

Fischer, C. and A. Luttge (2017). Beyond the conventional understanding of water–rock reactivity. Earth and Planetary Science Letters, 457: 100-105
J. Kulenkampff, M. Gründig, A. Zakhnini and J. Lippmann-Pipke (2016): Geoscientific process monitoring with positron emission tomography (GeoPET). Solid Earth, 7: 1217-1231

Acceptance of Terms and Conditions Click here to agree

Primary authors

Presentation Materials

There are no materials yet.