Rebrnice area lies on the NE slopes of the Upper Vipava Valley. There are many slope deposits of recent and fossil polygenetic landslides. In this area, the Mesozoic carbonates of the Hrušica nappe are thrusted on the Tertiary flysch rocks of the Snežnik nappe. The base rocks of the Rebrnice are marls, sandstones and rare calciturbidite layers. Overlying the flysch bedrock are stratified, complex Quaternary deposits.
In this area, landslides were formed through various transport mechanisms and deposition processes, which include sediments of debris flow and avalanche, grain flow and also deep-seated rotational and translational landslides.
In my master’s thesis I have been discussing the Quaternary deposits, especially slope screes and gravels. The stratified carbonate breccias of the deep – seated rotational landslides in the hinterlands of the Šumljak 3 sedimentary body were analysed. The Šumljak 3 sedimentary body is defined by several steep scarps, which define the border of the body. The breccia appears in layers with an inclination of up to 60°, which indicate the rotation of separate breccia blocks. The breccia was formed as a result of partial lithification of the talus, multiple escarpments indicate multiple rotational landslides. Ten blocks of carbonate breccia were identified and their height and layering, where visible, was measured.
Porosity was observed at the macroscopic level, the pores being mostly filled with carbonate cements, occasionally in the form of a dripstone. The clasts are mostly composed of micritic cements and they are of irregular shape. The largest grain from the taken samples measures about four cm.
I have described cements that appear as binders inside the pores. Up to four generations of cements were recorded. The cements occuring in the samples are: micritic, microstalactitic, mosaic, microsparite and sparite, ''dog-toothed'', mud matrix and tufa.
The first generation is always represented by micritic cement, outgrown with microstalacitic cement. These two are sometimes separated by a white line (microsparite or sparite cement). The third generation is usually represented by mosaic cement, which begins to grow fine grained, the size of the grains often increases towards the centre of the pore. The same goes with dog tooth cement, it also represents the third generation, in this case the mosaic cement growing out of the dog-tooth cement represents the fourth generation. Sometimes the muddy matrix appears in the second, third or fourth generation. Tufa is present occasionally and it represents the youngest, fourth generation.
The grains vary greatly in size and composition, but they are composed entirely of carbonate.
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