Osman, A.R.
wavelength. The meander width is 5 km same as the width of the mature part. The amplitude is 4.5 km. The same as that
of the mature part.
The surface width is ranging from 500 meters the narrowest and 1400 meters the widest part of young sample. The
meander belt is calculated as 100 km less than both samples (A) and (B). The mastermind of the Talweg is 29.6 km.
The channel length is 27.4 km showing the lowest reading of the three samples. The meander belt axis is 20.4 km. The
sinuosity index is calculated from the channel length and the meander belt axis. There are two islands observed.
The channel pattern or map view of a river is usually considered as straight, meandering or braided. However, there is a
platform between straight and meander which may be called sinuous (SCHMM, 1968). The sinuosity index (SI) has
been defined in a number of ways:
SI — Talwegs Length
Valleys Length
(LEOPOLD & WALMAN, 1957)
SI = lengths of channel
lengths of meanders belts Axis
(BRICE, 1964)
7. CONCLUSION AND RECOMMENDATIONS
The study showed that the remote sensing is very useful in mapping remote areas and its synoptic view could show the
huge geological actions. The meanders frequency is not systematic, so the meanders wavelength, the meander width and
the amplitudes are some-times ranging from one dimension to another even within the same stage of the channel. The
Blue Nile study showed that it is a meandering.
Further research work with carbon age (C14) is needed to find out the real dates of the three different areas. Remnants
from the three sites are needed for this type of work.
8. REFRENCES
1. BRICE (1964) Equation of sinuosity index: length of channel over length of the meander belt axis.
2. LEOPOLD, L.B. & WOLMAN, M. G. (1957) River Channels Patterns; Breaded , Meandering and Straight ;
U.S.Geol.Surv. Prof. Pap. 282-B.
3. OSMAN, AWR.O. (1990) The study of the Palaeochannels of the Blue Nile in the Gezira plain — 416 p. Gent;
Rijksuniversiteit - ITC for soil scientists Ph.D.Thesis.
4. VERSTAPPEN, H. T. H. (1977) Remote Sensing in Geomorphology. P. 214. Elsevier scientific publ. Company
Amsterdam. 5
1092 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000.