Grondwater in Nederland: Onzichtbaar water waarop wij lopen

Groundwater in the Netherlands: facts and figures

Ground penetrating radar for determining volumetric soil water content ; results of comparative measurements at two test sites

Ground penetrating radar (GPR) can provide information on the soil water content of the unsaturated zone in sandy deposits via measurements from the surface, and so avoids drilling. Proof of this was found from measurements of radar wave velocities carried out ten times over 13 months at two test sites in the Netherlands. At these same locations...

An extension of Box-Jenkins transfer/noise models for spatial interpolation of groundwater head series

This paper advocates an approach to extend single-output Box-Jenkins transfer/noise models for several groundwater head series to a multiple-output transfer/noise model. The approach links several groundwater head series and enables a spatial interpolation in terms of time series analysis. Our multiple-output transfer/noise model relates the...

An assessment of volcanic hazard on the islands of Saba and St.Eustatius in the northern Lesser Antilles

The penetration depth in modelling natural groundwater flow

In this paper, we present a method that may lead to a better quantitative insight into the relation between the size (horizontal dimensions) of a natural groundwater flow modelling area and the schematization required for a numerical model. The method is based on a decomposition of the spatial variability of the groundwater table into a Fourier...

Parallelisation of seismic algorithms using PVM and FORGE

The processing of seismic data, for the imaging of the earth's subsurface, is pushing current computational possibilities to the limit. In this paper results are presented obtained by optimisation and parallelisation of two innovative seismic algorithms with the use of PVM and FORGE. It shows that where the algorithm is CPU bound, a very...

Flow pattern analysis for a well defined by point sinks

This paper deals with the analytical description of single-phase flow caused by abstraction wells and governed by Darcy's law. Since we are mainly interested in the velocity field upon which an analysis of transport phenomena can be based, we may assume that the flow is quasi steady. A well may be composed of a number of point sinks, therefore...

Three-dimensional geomodelling for offshore aggregate resources assessment

Use of a three-dimensional geoscientific modelling system in offshore sand resources analysis is described. The benefits of a three-dimensional approach to geological modelling are that geologists can concentrate on geological interpretation without the constraints embodied in a two-dimensional approach and geological models can be used directly...

Modelling of permeability changes in argillaceous sandstones due to fluid injection

Injection of formation water can cause formation damage due to the

Onzekerheid in grondwatermodellering; verslag van de lezingendag 19 januari 1995, De Reehorst, Ede

EGIS: Geographical Information Systems (brochure)

Using Kalman Filtering to improve and quantify the uncertainty of numerical groundwater simulations 2. Application to monitoring network design

Integrating Kalman filtering and a deterministic groundwater flow model not only improves and quantifies the uncertainty of numerical groundwater simulation, but also provides the dynamic relation between the variance of the estimation error and the measurement strategy. This relation is applied to Zhengzhou city and Spannenburg for the analysis...

Using Kalman Filtering to improve and quantify the uncertainty of numerical groundwater simulations . The Role of System Noise and Its Calibration

Deterministic models are widely used to describe the behavior of the hydraulic head in time and space. It would be useful to know the uncertainty of these approximations of reality, what data on groundwater head they require and whether these data can be used to improve the model's performance after calibration/validation. Therefore the use of a...

Solution of surface water flow equations using Clebsch variables.

Conventionally, the flow equations for surface waters are obtained by integrating vertically the basic continuum conservation equations governing three‐dimensional motion, thus reducing the problem to two dimensions. However, when vertical transport is important, this model fails, and the basic equations for three‐dimensional motion must be...