Aggregate resources in the Netherlands
M.J. van der Meulen, S.F. van Gessel, J.G. Veldkamp
TNO Built Environment and Geosciences – Geological Survey of the Netherlands, P.O. Box 80015, 3508 TA Utrecht, the Netherlands.
We have built a 3D lithological model of the Netherlands, for the purpose of mapping on-land aggregate resources down to 50 m below the surface. The model consists of voxel cells (1000 · 1000 · 1 m), with lithological composition and aggregate content estimates as primary attributes. These attributes were derived from ~350,000 borehole descriptions. Overburdens and intercalations of cohesive or otherwise non-dredgeable materials were taken into account to define geologically exploitable aggregates within the total stock. We arrive at about 520 · 109 m³ of aggregates occurring in the depth range investigated. Some 50% of this amount is considered geologically exploitable and about 25% would in principle (but largely not in reality) be accessible. Most aggregates resources (~98%) are coarse sand, which is processed for use in concrete, masonry mortars, drains, filters, etc. The total exploitable stock of coarse sand in the depth range investigated amounts to roughly 7500 times the current annual consumption level, and is virtually indepletable. The gravel stock, estimated at some 12 · 109 m³, is small by comparison, and impels a dependency on imports. Exploitable aggregates occur in all but the coastal provinces. In accordance with current policy changes, the future may show a shift from concentrated production along the upstream Dutch Rhine and Meuse rivers towards a more even distribution of small-sized operations over the country. Fairly large aggregate stocks, that have not yet been exploited to significant extent, are available in the northern extent of the aggregates occurrences.
Keywords: Netherlands, sand, gravel, aggregates, resource assessment
In: Netherlands Journal of Geosciences 84(3), 379-387, 2005 (full text)