Application of
image-based granulometry to siliceous and calcareous estuarine and
marine sediment
Stanislav
FranCiSkovic-Bilinski1,
Halka Bilinski1,
Neda VdoviC1,
Yoganand
Balagurunathan2, and
Edward R. Dougherty2
1Department of
Physical Chemistry, Rudjer Boskovic Institute, POB 180, HR-10002 Zagreb,
Croatia
2Department of Electrical
Engineering, Texas A&M University, College Station, Texas 77846, USA
Grain size analysis has been studied for decades as a descriptor of
transport and depositional processes. For this paper we present the
possibility of using image-based granulometry to characterize granulometric
composition of loose sediments, as an alternative to classical techniques,
such as sieving and coulter counter analysis. Conventional sediment analysis
of siliceous and calcareous sediments was carried out and
compared to image-based analysis of sediments obtained along the Öre Estuary (Northern
Sweden) and the Adriatic Sea (Croatia and Italy). These grains have different
textural characteristics, composition, roundness and specific surface area.
Granulometric parameters are calculated using both a graphical method and the
mathematical method of moments. For proposed new method, grains were imaged
using a microscope and on these digital data,
mathematical granulometry was applied. Image-based granulometric moment descriptors
were compared with sieve+coulter counter-derived moments. Direct scale
sediment moment descriptors were compared to adapted granulometric moments
obtained for the entire sample. The results of granulometric-shape based
sizing to mass-based sieving processes are encouraging. They show the
potential of applying digital electronic imaging to granulometric analysis of
sediments. This idea, which could be realized in the future, can make the
analysis easier as one needs only to take photographs of sediments from its fractional
ranges using a high resolution digital camera linked to an on-board computer
to obtain the grain size distribution. In this way, sampling for
granulometric analysis and sieving processes combined with cumbersome coulter
counter analysis of fraction < 32 µm could be eliminated and a large area
of loose sediment surface could be covered in a short time.
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