Temperature changes and variations in pore fluid salinity may negatively affect the permeability of clay‐bearing sandstones with implications for natural fluid flow and geotechnical applications alike. Cheng and Milsch (2020) investigated these factors for a sandstone dominated by illite as the clay phase.
Flechtinger sandstone, a Lower Permian (Upper Rotliegend) sedimentary rock outcropping and commercially mined at the Sventesius Quarry near Flechtingen, Germany, was selected for the experiments. Three cylindrical cores were drilled from a larger block. Subsequently, samples were prepared with polished and plane-parallel end faces having a diameter of 30 mm and a length of 40 mm. The three samples were labelled FS1, FS3, and FS4, respectively. The three samples were vacuum-dried in an oven at 60 °C for 24 hours. They were then set under vacuum in a desiccator chamber for 10 hours and saturated with deionized water for another 24 hours.
All experiments were performed with two flow-through apparatuses with details described in Milsch et al. (2008). The saturated sample is jacketed with a Fluorinated Ethylene Propylene (FEP) heat shrink tubing and is then mounted in the vessel. Afterwards, the two sample ends are connected to the upstream and downstream pumps, respectively. The flow direction, generally, is from the bottom to the top side of the sample but can be reversed for return permeability measurements.
This report summarizes the measurements carried out by the GFZ Potsdam on the boreholes Gt S 6/17 and Gt S 7/20 in Schwerin (Mecklenburg-Western Pomerania). The first part of the report describes the borehole measurements of the unperturbed temperature profiles. The second part describes the compilation of the thermal-hydraulic rock properties (thermal conductivity, porosity, permeability, density, etc.) measured on drill-core material. The shut-in time since the drilling is around 4 years for Gt S 6/17 and around 21 months for Gt S 7/20. Hence, unperturbed borehole temperatures are assumed at the time of temperature logging.
These program codes are part of the manuscript entitled "Determining crack apertures distribution in rocks using 14C-PMMA autoradiographic method: experiments and simulations" by Bonnet et al. (2019)All the codes are including in one zip file. It contains:- one text file describing the content of the zip file {ReadMe.txt},- the program used under Geant4 for the simulations {Geant4_Program folder},- and the program used under the IDE Code::Blocks {CodeBlockEnergyProfiles.cpp}.
This data set is part of the manuscript entitled "Determining crack apertures distribution in rocks using 14C-PMMA autoradiographic method: experiments and simulations" by Bonnet, M., Sardini, P., Billon, S., Siitari-Kauppi, M., Kuva, J., Fonteneau, L., & Caner, L. which is currently under review in Journal of Geophysical Research: Solid Earth.All the data set are including in one zip file. It contains:- one text file describing the content of the zip file {ReadMe.txt},- the raw data of the energy profiles obtained by simulations {RawDataEnergyProfiles folder},- one excel file with the data extracted from the energy profiles with Code::Blocks {DataExtractedEnergyProfiles.xlsx},- one image file of two artificial samples (at left with a real aperture of 96 µm and a tilt angle of 90°; at right with a real aperture of 189 µm and a tilt angle of 20°) {ExEch.pdf},- one image file of the scan autoradiograph of perpendicular artificial cracks {AG_Texp8h_1200dpi_Ech90deg.pdf},- and one image file of the scan autoradiograph of tilted artificial cracks {AG_Texp8h_1200dpi_EchTilted.pdf}.The authors provide raw data from the simulations (.txt and .xlsx), as well as some photos of the experimental part (.pdf).Raw data from the simulations are energy profiles (.txt) obtained with Geant4 toolkit. The simulated object is an artificial crack sample in-filled with a radioactive resin (14C-MMA) which is in contact with an autoradiographic film (also simulated), simulating the 14C-PMMA autoradiographic method. Crack aperture and tilt angle (of the crack to the autoradiographic plane) are varying parameters (from [0.1; 1000] µm and from [10; 90]°, respectively).Other raw data from the simulations is one excel file with the data extracted from the energy profiles with the IDE Code::Blocks, for data analysis purposes.Three photos of the experimental part of the article are also made available. One image file of two artificial samples with different crack aperture and tilt angle; one image file of the scan autoradiograph of perpendicular artificial cracks; and one image file of the scan autoradiograph of tilted artificial cracks.