Jezero pod Krimom, prispevek k poznavanju jezera in okolice

Abstract

The contact between the young tectonic depression represented by the
Ljubljan a Moor (Ljubljansko barje) and the Dinaric Karstic mountains,
though teetonically conditioned, shows nevertheless its fringe mountains cut
by valleys and by two interesting Karstic basins: Ponikve and the basin of
the Podpeč (Krim) Lake.
The basin of the Podpeč (Krim) Lake could be considered as a simple
extension of the Ljubljan a Moor, had not its swampy alluvial floor which
is situated 289'—295 above sea level been separated fro m the Ljubljan a Moor
by a ca 10 m high rocky terrace. The remaining limestone slopes which
surround the basin are considerably higher and reach an altitude of up to
and even more than 600 m above sea level. They consist of elevations belonging to the Krim Mountain system. There are six Karstic sources that flow into the basin from its Karstic hinterland. The data regarding the
temperature and the chemical composition of these waters can be seen on
the page Nr. 217. They flow jointly int o the lake which is 135 m long and
120 m wide. The lake has no surface efflux . In the funnel-shaped basin of
the lake whose floor is covered b y the lake's mu d a chasm has been discovered in its rocky floor whose depth has been measured down to 46,4 m.
Through this chasm waters from the lake flow underground into a source
which comes out at a distance of ca 300 m at the edge of the Ljubljana
Moor. Thus the depth of this small Karstic lake surpasses the depth of the
largest Slovene lake, the lake of Bohinj (44,5 m) and it is in all probability
the deepest lake in Slovenia since we do not consider as a lake the chasm
at the source of the Kolpa River (67 m), in the border area with Croatia.
With hand drillings into the part of the floor of the basin which is
periodically covered with water a nearly 5 m thick stratum of lake chalk
containing large quantities of shells has been established. This is the sediment of the "pile-dwellers' lake" whose surface of 289 m s. 1. had caused that a lake had also been developed in the basin of the Podpeč (Krim) Lake.
The pollen analysis of the lacustrine sediments is now going to be made.
Geomorphologic traces found in the border area of the basin betray that
there had also been an older lake with its surface at 295—300 m above sea
level. According to Melik, its origin was conditioned by the accumulation
of the gravel brought by the Sava River into the Ljubljan a Field (Ljubljansko polje).