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A natural-stone city walk through Maastricht, the Netherlands

Dubelaar, C.W. (author), Kisters, P.J.M. (author), Stroucken, J.W. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

Having been inspired by the leaflet 'Natuursteen in Maastricht. Aardrijkskunde in een oude stad', written by P.J. Felder and published in 1977, we here present descriptions of the main types of natural stones applied in the city of Maastricht. A concise overview of the provenance area, mineralogy and physical properties of a selection of so...

article 2011

document

Use of CFD for calculation of dispersion of LPG along rail transport routes situated above or below ground level

Trijssenaar-Buhre, I.J.M. (author), Reinders, J.E.A. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

The use and transport of dangerous substances may pose a risk to people present in the vicinity. Well known examples of dangerous substances are the very toxic chemical chlorine and the extremely flammable Liquefied Petroleum Gas (LPG). The adverse effects of accidental releases of such materials may reach considerable distances. A Computational...

conference paper 2010

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Extent of immobilisation of phosphate during aeration of nutrient-rich, anoxic groundwater

Griffioen, J. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

Nutrient-rich exfiltrating groundwater may impose a heavy phosphate load on surface water systems. However, iron oxides that bind PO4 precipitate fast upon oxygenation at neutral pH and PO4 may also become bound in Ca precipitates following upon pH increase, so load estimates based on conservative behaviour during exfiltration will be...

article 2006

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Sedimentary trace element records over the last 200 kyr from within and below the northern Arabian Sea oxygen minimum zone

Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author), van der Weijden, C.H. (author), Reichart, G.J. (author), van Os, B.J.H. (author)

Two piston cores (PCs), containing two full glacial cycles, were retrieved at Murray Ridge. One core (PC463) contains sediment deposited at 920 mbsl within, the other (PC464) has sediment deposited at 1470 mbsl below the current oxygen minimum zone, OMZ (O2: ≤ 2 μM). Variations in the organic carbon (OC) content correlate well between the two...

article 2006

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A semi-analytical model for productivity testing of multiple wells

Fokker, P.A. (author), Brouwer, G.K. (author), Verga, F. (author), Ferrera, D. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

This paper presents a new, semi-analytical method for calculation of the productivity of vertical, horizontal or multilateral wells draining either gas or oil reservoirs. Well interference effects and the presence of natural or induced fractures are accounted for. The method is based on an earlier derived productivity prediction tool in which...

conference paper 2005

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Sensitivity analysis and model type evaluation for subsidence above offshore gas reservoirs

Pruiksma, J.P. (author), Teunissen, J.A.M. (author), Barends, F.B.J. (author), Orlic, B. (author), Cassiani, G. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

This paper describes the results of a sensitivity study conducted to understand how the prediction of subsidence due to gas extraction from offshore gas fields depends on a few key parameters, such as connection to the adjacent aquifers and material mechanical properties. The analysis has been performed using an axi-symmetric FE-model. A...

conference paper 2005

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Field experiment of ECBM-CO₂ in the upper Silesian Basin of Poland (RECOPOL)

Pagnier, H.J.M. (author), van Bergen, F. (author), Kreft, E. (author), van der Meer, L.G.H. (author), Simmelink, H.J. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

The RECOPOL project is an EC-funded research and demonstration project to investigate the technical and economic feasibility of storing CO₂ permanently in subsurface coal seams. This is considered to be an option for CO₂ sequestration, which will be required to meet the Kyoto protocol. The main aim is to demonstrate that CO...

conference paper 2005

document

The mechanical impact of CO2 injection

Orlic, B. (author), Schroot, B. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

The mechanical impact of CO2 injection into a depleted hydrocarbon field or aquifer is caused by changes in the stress field, resulting from changes in the pore pressure and volume of the rock. Mechanical processes can lead to the loss of reservoir and caprock integrity, and the reactivation of existing faults. A geomechanical numerical...

conference paper 2005

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Processes controlling the dynamics of compound sand waves in the North Sea, Netherlands

Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author), van Dijk, T.A.G.P. (author), Kleinhans, M.G. (author)

The understanding of the morphodynamics of harmonic bed forms on the seabed is essential for modeling marine sediment transport and coastal morphologic development. Previous research has mainly focused on the type and distribution of bed forms, but areally extensive data and time series of seabed features are scarce. Multibeam and side‐scan...

article 2005

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4D Seismic Imaging of an Injected C02 Plume at the Sleipner Field, Central North Sea

Chadwick, R.A. (author), Arts, R. (author), Eiken, O. (author), Kirby, G.A. (author), Lindeberg, E. (author), Zweigel, P. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

C02 produced at the Sleipner field is being injected into the Utsira Sand, a major saline aquifer. Time-lapse seismic data acquired in 1999, with 2.35 million tonnes of C02 in the reservoir, image the C02, plume as a number of bright sub-horizontal reflections. These are interpreted as tuned responses from thin (< 8 m thick) layers of C02...

article 2004

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The edge-based face element method for 3D-stream function and flux calculations in porous media flow

Zijl, W. (author), Nawalany, M. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

We present a velocity-oriented discrete analog of the partial differential equations governing porous media flow: the edge-based face element method. Conventional finite element techniques calculate pressures in the nodes of the grid. However, such methods do not satisfy the requirement of flux continuity at the faces. In contrast, the edge...

article 2004

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A direct method for the identification of the permeability field based on flux assimilation by a discrete analog of Darcy's law

Zijl, W. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

Inverse models to determine the permeability are generally based on existing forward models for the pressure. The permeabilities are adapted in such a way that the calculated pressures match the specified pressures in a number of points. To assimilate a priori knowledge about the flux, we introduce the 'flux assimilation method', which is based...

article 2004

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Predicting ground deformation due to CO2 injection: Examples from Montmiral, France, Sleipner, Norway and Florina, Greece

Orlic, B. (author), Schroot, B.M. (author), Wensaas, L. (author), Heggland, R. (author), Hatziyannis, G. (author), Nikolaou, N. (author), Poyatzi, E. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

conference paper 2004

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The spatial distribution of groundwater age for different geohydrological situations in the Netherlands: Implications for groundwater quality monitoring at the regional scale

Broers, H.P. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

The spatial distribution of groundwater age is a key factor determining the distribution of dissolved contaminants in the subsurface when contamination loadings have increased in time. The effects of surficial drainage and aquifer heterogeneity on the spatial distribution of groundwater age in unconsolidated aquifers in flat areas were...

article 2004

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Regional monitoring of temporal changes in groundwater quality

Broers, H.P. (author), van der Grift, B. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

Changes in agricultural practices are expected to affect groundwater quality by changing the loads of nutrients and salts in recharging groundwater, but regional monitoring networks installed to register the changes often fail to detect them and interpretation of trend analysis results is difficult. This study aims to improve the detection and...

article 2004

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State-space modeling of water table fluctuations in switching regimes

Berendrecht, W.L. (author), Heemink, A.W. (author), van Geer, F.C. (author), Gehrels, J.C. (author), Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author)

A nonlinear state-space model is developed for describing water table fluctuations in groundwater systems that are influenced by drains. As drains are only active if the water table is above drainage level, the regime of the system switches at the drainage level. The water table depth is related to observations on precipitation and...

article 2004

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The geometry and stratigraphic position of the Maassluis Formation (western Netherlands and southeastern North Sea)

Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author), Jansen, H.S.M. (author), Huizer, J. (author), Dijkmans, J.W.A. (author), Mesdag, C. (author), van Hinte, J.E. (author)

The geometry and depositional history of the Maassluis Formation is described from an East-West oriented transect located in the west-central Netherlands and P- and Q-blocks in the Dutch offshore area. The Late Pliocene to Early Pleistocene Maassluis Formation was deposited under near coastal marine conditions. Two distinct facies are...

article 2004

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Strontium (87Sr/86Sr) dating of marine shells from pliocene and pleistocene shallow marine deposits in The Netherlands

Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author), Jansen, H.S.M. (author), Huizer, J. (author), Dijkmans, J.W.A. (author), van Hinte, J.E. (author)

87Sr/86Sr (Strontium) ratio analyses of shell material (mainly Arctica islandica) from 24 levels in the Maassluis Formation of boreholes Noordwijk, Zegveld and Terschelling suggest that the age of the formation ranges from 0.82 to 2.34 Ma (± 0.5 Ma), and that the Oosterhout Formation at Noordwijk could be as much as 2.5 Ma older than hitherto...

article 2004

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Seismisch hazard van geinduceerde aardbevingen: integratie van deelstudies

Nederlands Instituut voor Toegepaste Geowetenschappen TNO Koninklijk Nederlands Meteorologisch Instituut (author), Wassing, B.B.T. (author), van Eck, T. (author), van Eijs, R.M.H.E. (author)

TNO-NITG, TNO Bouw en het KNMI hebben de afgelopen twee jaar een aantal studies uitgevoerd, bedoeld om de aspecten die invloed hebben op het seismisch risico ten gevolge van bevingen, geïnduceerd door de olie- en gaswinning, systematisch in kaart te brengen en het risico op basis van de nu bekende kennis en gegevens te kwantificeren. De...

report 2004

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Effect of aerosols on the downward shortwave irradiances at the surface: Measurements versus calculations with MODTRAN4.1

Nederlands Instituut voor Toegepaste Geowetenschappen TNO (author), Henzing, J.S. (author), Knap, W.H. (author), Stammes, P. (author)

article 2004