Influence of bacteria on rock-water interaction and clay mineral formation in subsurface granitic environments

AbstractStudies of the subsurface microbiology of the Äspö Hard Rock Laboratory, Sweden have revealed the presence of many different bacteria in the deep groundwaters which appear to maintain reducing conditions. Experiments were conducted to study the rock-water and microbial interactions. These used crushed Äspö diorite, Äspö groundwater and iron- and sulphate-reducing bacteria in flowing systems under anaerobic conditions. In column experiments, there was evidence of loss and mobilization of fine-grained crushed material (<5 μm) which had originally adhered to grain surfaces in the starting material. The mobilized fines were trapped between grains. The degree of mineralogical alteration was greater in the experiments when bacteria were present. In both column and continuously stirred reactor experiments, there is evidence for the formation of a secondary clay. These experiments have shown that microbial activity can influence rock-water interactions even in nutrient-poor conditions.

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Siderophore Production by Pseudomonas stutzeri under Aerobic and Anaerobic Conditions

Applied and Environmental Microbiology ◽

10.1128/aem.00072-07 ◽

2007 ◽

Vol 73 (18) ◽

pp. 5857-5864 ◽

Cited By ~ 33

Author(s):

Sofia A. Essén ◽

Anna Johnsson ◽

Dan Bylund ◽

Karsten Pedersen ◽

Ulla S. Lundström

Keyword(s):

Mass Spectrometry ◽

Hard Rock ◽

Bacterial Culture ◽

Pseudomonas Stutzeri ◽

Siderophore Production ◽

Anaerobic Conditions ◽

Rock Laboratory ◽

Molecular Masses ◽

Aerobic And Anaerobic ◽

Aerobic And Anaerobic Conditions

ABSTRACT The siderophore production of the facultative anaerobe Pseudomonas stutzeri, strain CCUG 36651, grown under both aerobic and anaerobic conditions, was investigated by liquid chromatography and mass spectrometry. The bacterial strain has been isolated at a 626-m depth at the Äspö Hard Rock Laboratory, where experiments concerning the geological disposal of nuclear waste are performed. In bacterial culture extracts, the iron in the siderophore complexes was replaced by gallium to facilitate siderophore identification by mass spectrometry. P. stutzeri was shown to produce ferrioxamine E (nocardamine) as the main siderophore together with ferrioxamine G and two cyclic ferrioxamines having molecular masses 14 and 28 atomic mass units lower than that of ferrioxamine E, suggested to be ferrioxamine D2 and ferrioxamine X1, respectively. In contrast, no siderophores were observed from anaerobically grown P. stutzeri. None of the siderophores produced by aerobically grown P. stutzeri were found in anaerobic natural water samples from the Äspö Hard Rock Laboratory.

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Interaction of Corroding Iron with Eight Bentonites in the Alternative Buffer Materials Field Experiment (ABM2)

Minerals ◽

10.3390/min11080907 ◽

2021 ◽

Vol 11 (8) ◽

pp. 907

Author(s):

Paul Wersin ◽

Jebril Hadi ◽

Andreas Jenni ◽

Daniel Svensson ◽

Jean-Marc Grenèche ◽

...

Keyword(s):

Redox Reactions ◽

Hard Rock ◽

High Spatial Resolution ◽

X Ray Diffraction ◽

X Ray ◽

Rock Laboratory ◽

Reducing Conditions ◽

Buffer Material ◽

High Level ◽

Redox Evolution

Bentonite, a common smectite-rich buffer material, is in direct contact with corroding steel in many high-level radioactive waste repository designs. The interaction of iron with the smectite-rich clay may affect its swelling and sealing properties by processes such as alteration, redox reactions and cementation. The chemical interactions were investigated by analysing the Fe/clay interfaces of eight bentonite blocks which had been exposed to temperatures up to 130 °C for five years in the ABM2 borehole at the Äspö Hard Rock Laboratory managed by the Swedish Nuclear Fuel and Waste Management Co (SKB). Eleven interface samples were characterised by high spatial resolution methods, including scanning electron microscopy coupled with energy dispersive X-ray spectroscopy and μ-Raman spectroscopy as well as by “bulk” methods X-ray diffraction, X-ray fluorescence and 57Fe Mössbauer spectrometry. Corrosion induced an iron front of 5–20 mm into the bentonite, except for the high-Fe bentonite where no Fe increase was detected. This Fe front consisted mainly of ferric (oxyhydr)oxides in addition to the structural Fe in the smectite fraction which had been partially reduced by the interaction process. Fe(II) was also found to extend further into the clay, but its nature could not be identified. The consistent behaviour is explained by the redox evolution, which shifts from oxidising to reducing conditions during the experiment. No indication of smectite alteration was found.

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Diversity of Iron Oxidizing and Reducing Bacteria in Flow Reactors in the Äspö Hard Rock Laboratory

Geomicrobiology Journal ◽

10.1080/01490451.2014.884196 ◽

2015 ◽

Vol 32 (3-4) ◽

pp. 207-220 ◽

Cited By ~ 13

Author(s):

Danny Ionescu ◽

Christine Heim ◽

Lubos Polerecky ◽

Alban Ramette ◽

Stefan Haeusler ◽

...

Keyword(s):

Hard Rock ◽

Flow Reactors ◽

Rock Laboratory ◽

Reducing Bacteria

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Biologically Induced Clay Formation in Subsurface Granitic Environments

MRS Proceedings ◽

10.1557/proc-807-841 ◽

2003 ◽

Vol 807 ◽

Author(s):

Victoria A. Tuck ◽

J. M. West ◽

K. Bateman ◽

P. Coombs ◽

A. E. Milodowski ◽

...

Keyword(s):

Local Level ◽

Chemical Species ◽

Microbial Interactions ◽

Batch Reactors ◽

Ph Change ◽

Fine Grained ◽

Reducing Conditions ◽

Bulk Scale ◽

Abiotic Controls ◽

Clay Formation

ABSTRACTExperiments were conducted to identify the rock-water and microbial interactions influencing accelerated smectite-clay formation. Packed columns and stirred batch reactors contained Äspö granodiorite, artificial groundwater mimicking that from Äspö and combinations of three types of subsurface chemolithotrophic bacteria, two of which were indigenous to the Äspö rocks. Results showed evidence that, within 5 days under anaerobic reducing conditions, all three of the bacterial types produced copious biofilamentous ‘meshes’ across porespaces, apparently using the larger grains as anchor points. The biofilaments quickly became encrusted with fine grained material and surrounded with neoformed clay-like deposits. In contrast, the abiotic controls showed little or no evidence of clay formation suggesting that this process is biologically induced or controlled. A second series of abiotic experiments to determine the effects of increased acidity showed evidence of mineral pitting and dissolution along with an increase in concentration of soluble species thought to be important in smectite formation (i.e. Si, Al, Mg, Fe, Ca, Na). However, there was no evidence of clay formation, and the biotic experiments showed no signs of bulk scale pH change, suggesting that either the bacteria are actively concentrating relevant chemical species at a local level or they are acting as templates or nucleation points for clay formation.

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Profiling of human burned bones: oxidising versus reducing conditions

Scientific Reports ◽

10.1038/s41598-020-80462-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

M. P. M. Marques ◽

D. Gonçalves ◽

A. P. Mamede ◽

T. Coutinho ◽

E. Cunha ◽

...

Keyword(s):

Inelastic Neutron Scattering ◽

Inelastic Neutron ◽

Skeletal Remains ◽

Anaerobic Conditions ◽

Human Skeletal Remains ◽

Human Bones ◽

Reducing Conditions ◽

Wide Range ◽

Burned Bones ◽

Vibrational Bands

AbstractComplementary optical and neutron-based vibrational spectroscopy techniques (Infrared, Raman and inelastic neutron scattering) were applied to the study of human bones (femur and humerus) burned simultaneously under either aerobic or anaerobic conditions, in a wide range of temperatures (400 to 1000 °C). This is the first INS study of human skeletal remains heated in an oxygen-deprived atmosphere. Clear differences were observed between both types of samples, namely the absence of hydroxyapatite’s OH vibrational bands in bone burned anaerobically (in unsealed containers), coupled to the presence of cyanamide (NCNH2) and portlandite (Ca(OH)2) in these reductive conditions. These results are expected to allow a better understanding of the heat effect on bone´s constituents in distinct environmental settings, thus contributing for an accurate characterisation of both forensic and archaeological human skeletal remains found in distinct scenarios regarding oxygen availability.

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Viruses in granitic groundwater from 69 to 450 m depth of the Äspö hard rock laboratory, Sweden

The ISME Journal ◽

10.1038/ismej.2008.18 ◽

2008 ◽

Vol 2 (5) ◽

pp. 571-574 ◽

Cited By ~ 51

Author(s):

Jennifer E Kyle ◽

Hallgerd S C Eydal ◽

F Grant Ferris ◽

Karsten Pedersen

Keyword(s):

Hard Rock ◽

Rock Laboratory ◽

Granitic Groundwater

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Modelling the Prototype Repository

Geological Society London Special Publications ◽

10.1144/sp482.15 ◽

2018 ◽

Vol 482 (1) ◽

pp. 241-260 ◽

Cited By ~ 1

Author(s):

V. Tsitsopoulos ◽

S. Baxter ◽

D. Holton ◽

J. Dodd ◽

S. Williams ◽

...

Keyword(s):

Numerical Modelling ◽

Host Rock ◽

Hard Rock ◽

Task Force ◽

Fractured Rock ◽

Fracture Network ◽

Atmospheric Conditions ◽

Predictive Capability ◽

Rock Laboratory ◽

Modelling Methodology

AbstractThe Prototype Repository (PR) tunnel is located at the Äspö Hard Rock Laboratory near Oskarshamn in the southeast of Sweden. In the PR tunnel, six full-sized deposition holes (8.37 m deep and 1.75 m in diameter) have been constructed. Each deposition hole is designed to mimic the Swedish reference system for the disposal of nuclear fuel, KBS-3V. The PR experiment is designed to provide a full-scale simulation of the emplacement of heat-generating waste. There are three phases to the experiment: (1) the open tunnel phase following construction, where both the tunnel and deposition holes are open to atmospheric conditions; (2) the emplacement of canisters (containing heaters), backfill and seal in the first section of the tunnel; and (3) the emplacement of canisters, backfill and seal in the second section of the tunnel. This work describes the numerical modelling, performed as part of the engineered barrier systems (EBS) Task Force, to understand the thermo-hydraulic (TH) evolution of the PR experiment and to provide a better understanding of the interaction between the fractured rock and bentonite surrounding the canister at the scale of a single deposition tunnel. A coupled integrated TH model for predicting the wetting and the temperature of bentonite emplaced in fractured rock was developed, accounting for the heterogeneity of the fractured rock. In this model, geometrical uncertainties of fracture locations are modelled by using several stochastic realizations of the fracture network. The modelling methodology utilized information available at early stages of site characterization and included site statistics for fracture occurrence and properties, as well as proposed installation properties of the bentonite. The adopted approach provides an evaluation of the predictive capability of models, it gives an insight of the uncertainties to data and demonstrates that a simplified equivalent homogeneous description of the fractured host rock is insufficient to represent the bentonite resaturation.

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Electric resistivity and seismic refraction tomography, a challenging joint underwater survey at Äspö Hard Rock Laboratory

10.5194/se-2016-157 ◽

2016 ◽

Cited By ~ 1

Author(s):

Mathias Ronczka ◽

Kristofer Hellman ◽

Thomas Günther ◽

Roger Wisen ◽

Torleif Dahlin

Keyword(s):

Nuclear Power ◽

Hard Rock ◽

Seismic Refraction ◽

Three Dimensional ◽

Test Site ◽

Fracture Zones ◽

Rock Laboratory ◽

Refraction Tomography ◽

Local Point ◽

General Test

Abstract. Tunnelling below water passages is a challenging task in terms of planning, pre-investigation and construction. Fracture zones in the underlying bedrock lead to low rock quality and thus reduced stability. For natural reasons they tend to be more frequent at water passages. Ground investigations that provide information of the subsurface are necessary prior to the construction phase, but can be logistically difficult. Geophysics can help close the gaps between local point information and produce subsurface images. An approach that combines seismic refraction tomography and electrical resistivity tomography has been tested at the Äspö Hard Rock Laboratory (HRL). The aim was to detect fracture zones in a well-known but logistically and, from a measuring perspective, challenging area. The presented surveys cover a water passage along a part of a tunnel that connects surface facilities with an underground test laboratory. The tunnel is approximately 100 m below and 20 m east of the survey line and gives evidence for one major and several minor fracture zones. The geological and general test site conditions, e.g. with strong powerline noise from the nearby nuclear power plant, are challenging for geophysical measurements. Co-located positions for seismic and ERT sensors and source positions are used on the 450 m long underwater section of the 700 m long profile. Because of a large transition zone that appeared in the ERT result and the missing coverage of the seismic data, fracture zones at the southern and northern part of the underwater passage cannot be detected by separated inversion. A simple synthetic study shows significant three dimensional artefacts corrupting the ERT model that have to be taken into account while interpreting the results. A structural coupling cooperative inversion approach is able to image the northern fracture zone successfully. In addition, previously unknown sedimentary deposits with a significant large thickness are detected in the otherwise unusually well documented geological environment. The results significantly improve imaging of some geologic features, which would have been not detected or misinterpreted otherwise, and combines the images by means of cluster analysis to a conceptual subsurface model.

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