Geoscience Reference
In-Depth Information
set(h,'LineStyle','none')
axis equal
title('Slope [°]')
[r c] = size(slp);
axis([1 c 1 r])
set(gca,'TickDir','out');
Flat areas are common on the summits and on the valley l oors. h e south-
eastern and south-south-western sectors are also relatively l at. h e steepest
slopes are concentrated in the center of the area and in the south-western
sector. Next, a pseudocolor map of the aspect is generated (Fig. 7.15 c).
h = pcolor(asp);
colormap(hsv), colorbar
set(h,'LineStyle','none')
axis equal
title('Aspect')
[r c] = size(asp);
axis([1 c 1 r])
set(gca,'TickDir','out');
h is plot displays the aspect in degrees, clockwise from north. For instance,
mountain slopes facing north are displayed in red and east-facing slopes in
green.
h e aspect changes abruptly along the ridges of the mountain ranges
where neighboring drainage basins are separated by
watersheds
. h e Image
Processing Toolbox includes the function
watershed
to detect these drainage
divides and to ascribe numerical labels to each catchment area, starting with
1.
watersh = watershed(SRTM);
h e catchment areas are displayed in a pseudocolor plot in which each area
is assigned a color from the color table
hsv
(Fig. 7.15 d), according to its
numerical label.
h = pcolor(watersh);
colormap(hsv), colorbar
set(h,'LineStyle','none')
axis equal
title('Watershed')
[r c] = size(watersh);
axis([1 c 1 r])
set(gca,'TickDir','out');
h e watersheds are represented by a series of red pixels. h e largest
catchment area corresponds to the medium blue region in the center of the
map. To the north-west, this large catchment area appears to be bordered by
