Rakovska kukava - collapse or tumour doline?
France Šušteršič - (27/1,1998)
This paper deals with one of the largest presumed collapse dolines lying about 2km northeast of the Planinsko polje in Slovenia. Within it, true rock faces are only locally present. The rest of the rocky slopes are to some degree inclined, and many of them are only slightly too steep to support a soil mantle ("normal slopes"). Screes are found in the central part of the doline. In the lowest part of the depression a 45m-long and 20m-wide secondary depression lowered into the screes is evident that leads to the conclusion that, after scree slope formation under one set of slope equilibrium conditions, a subsequent process has removed material from the centre. This was confirmed by mathematical model. The process may continue until so much rock is removed that the stream appears on the surface.