Page 261 - Changing Living Spaces

The Neverlake: Water and Land Management in a Dry and Soilless Place

0.1 km2 (10 ha). The northwestern edge of the doline is at an elevation of
about 250 m, while the southeastern edge is about 10 m higher. The deep-
est point of the Jezero doline is at an elevation of 219.8 m on the ponor,
while the ‘Neverlake’ itself is about 2 m higher.
Six erosional gullies extend into the doline. The longest gully descends
from an elevation of 393 m, is about 800 m long, and has a stream gradi-
ent of 17.9 percent. Where it exits the doline, it has formed an alluvial fan,
i.e. a fan-shaped rubble-gravel-sand fill, on which people have created cul-
tivable land. The erosion gully extends noticeably deeper into the slopes
of Stena in the south and Škurovca in the north. The deepest part of the
erosion gully is about 500 m long. As can be seen from the geological map,
a minor fault (Jurkovšek, Tešović, and Kolar Jurkovšek 2013) runs along
the axis of the above-mentioned gully, which certainly influenced its for-
mation and depth. The blocks that shift along the fault planes fracture
the rocks. These fractured rocks are more susceptible to erosional-den-
udational processes than solid rocks, which means that vertical erosion
can deepen the gullies or valleys faster and that the corrosion process is
stronger in the fractured carbonate rocks. The stream-gradient of the ero-
sional gully becomes much lower as it enters the doline; at a distance of
just over 500 m from the ‘Neverlake’ it is only 5.7 percent and toward the
ponor it is even less (4.4 percent). A little further south, an erosion gul-
ly about 400 m long with a 21.2 percent slope enters the upper part of the
doline; still further south is a 350 m long erosion gully with a 20 percent
slope (called the ‘Nad Jezerom’ (‘Above the Lake’) area). On the basic top-
ographic map of this area at the scale of 1 : 5,000, an intermittent wa-
tercourse is marked. Three smaller erosion gullies extend into the doline
from the south.
The formation of the Jezero doline with its associated erosional gul-
lies can be explained as the inherited remnant of a system of a larger val-
ley and lateral erosional gullies from the pre-karst phase of the area, be-
fore the flysch thrust sheet was removed by erosion and corrosion. At
that time, surface waters were still flowing from the edge of the Karst
near Štanjel towards the river basin of the predecessor of today’s Branica,
or perhaps Raša, river. After the flysch thrust sheet was eroded, the de-
pression of the valley in the area of today’s ‘Neverlake’ and the associated
erosion gullies lagged behind the lowering of the Branica valley, so that
the valley was cut off and hung over the bottom of the Branica valley. It
is likely that, at least in the early stages, a larger amount of gravel com-
posed of carbonate and flysch remained in the depression. This gravel ac-

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