W. Devos et al., GEOCHEMICAL MAPPING BASED ON OVERBANK SEDIMENTS IN THE HEAVILY INDUSTRIALIZED BORDER AREA OF BELGIUM, GERMANY AND THE NETHERLANDS, Journal of geochemical exploration, 56(2), 1996, pp. 91-104
The geochemical distribution patterns based on overbank and stream sed
iments were studied in the border region of Belgium, Germany and the N
etherlands. In total 34 sites were sampled over an area of approximate
ly 16,000 km(2). Geologically the region comprises formations of the P
alaeozoic Ardennes and Eifel, and the unfolded Mesozoic to Quaternary
cover. Two overbank sediment samples were collected at each site; one
from the lower part of the profile and another from the upper. In addi
tion, samples of active stream sediment were taken from the same sites
for comparison and complementary geochemical information, Geochemical
distribution patterns for the lower overbank sediment samples reflect
the natural situation, with lithology as the main influencing factor.
Natural anomalous patterns, due to Pb and Zn mineralization, are also
detectable. The upper overbank sediment clearly shows the influence o
f Pb-Zn mining and metallurgy, as well as other anthropogenic chemical
contamination. Pollution is even stronger in stream sediment, obscuri
ng almost completely the natural pattern. The results of these investi
gations demonstrate the applicability of overbank sediment as a sample
medium in regional geochemical mapping. However, for an effective int
erpretation of the results a good knowledge of the sedimentological hi
story and age of the sample sites is required in mining and industrial
areas.