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V casu med eocenom in pliocenom so bile s temena krednega apnencevega antiklinorija v osrednjem in zahodnem delu planote Kras in s kozinsko-podgrajske antiklinale erodirane flisne plasti, zaradi cesar se je ob splosnem zniževanju okoliske ravnine ob pogojih zajezenega krasa razsirjal in zniževal ravnik na razkritih apnencih. Najvecji del planote Krasa predstavlja najstarejsi del kraskega ravnika. Na Krasu so se v pliocenu in kvartarju pasovi ravnika hitreje zniževali v smeri proti SZ, vmesno zastajajoce ali dvigujoce se povrsje pa je s tem dobilo obliko vzpetin na severozahodnem robu planote. Zaradi hitrejsega grezanja vipavske sinklinale so vodni tokovi prenehali teci preko planote Krasa se preden je bil flis, ki jim je prepreceval pot proti jugu, odstranjen zaradi grezanja severnega dela Tržaskega zaliva. Zaradi tega na Krasu ni slepih dolin ali polj. Pac pa je veliko vrtac, povrsje je kamnito, zaradi cesar je iz Krasa nastal splosni pojem kras. Obe znacilnosti sta tipicni za submediteranske dinarske kraske ravnike, gosto naseljene in obdelane ter zaradi tega brez gozdov Between Eocene and Pliocene, erosion of flysch strata on the top of Cretaceous limestone anticlinorium in the central and western part of the Kras plateau and the Kozina-Podgrad anticline uncovered and widened – and simultanously lowered - the karst plain in the conditions of dammed karst. The largest portion of Kras plateau is covered with karst plain, its oldest part. In Pliocene, the karst plain was fractured and subsided towards the NW regardless of older folded structure; during this process, several zones of elevations were formed through slower subsiding or uplifting. Due to faster lowering of the Vipava syncline, water streams stopped running over the Kras plateau before the flysch, damming the waters from the Kras plateau to the south was removed due to the subsiding in the northern Gulf of Trieste. Thus, no fossil blind valleys or poljes are found on the Kras plateau. However, there is considerable density of dolines and the surface is stony, giving the karst its original name. Both phenomena are typical of deforrested, densely populated and cultivated Submediterranean Dinaric karst plains.

Namen te študije je pokazati tektonske poteze v izbranih kraških poljih in manjših kotanjah Dinarskega krasa. Vrtine in gravimetrične meritve so ugotovile debele neogene nesprijete sedimente in apneniško dno pod gladino morja - kriptodepresije. Sedimenti so deli obsežne akumulacijske ravnine, ugreznjeni v kraška polja v spodnjem pliocenu. Seizmična aktivnost v sedanjosti nakazuje še trajajočo tektonsko aktivnost. Najgloblje (čez 100 m) in najmanjše kraško polje v slovenskem Dinarskem krasu, Globodol, je suho kraško polje v piezometrični vodni gladini. Pliokvartarno grezanje dna je edina možna razlaga za nastanek polja. Na Planinskem polju so znaki podtalne korozije in holocenskega tektonskega grezanja dna. Štiri kraška polja v Ravnih kotarih (Dalmacija) dokazujejo proces uravnavanja jezerskega dna pod plitvim pokrovom aluvialnih sedimentov. Izjemno globoke majhne kotanje so okoli 450 m globoko Rdeče jezero (Hercegovina) in kotanji pri Črnomlju in Kočevju (Slovenija), okoli 300 m oziroma 100 m pod gladino morja. The aim of this study is to show tectonic features in selected poljes and minor basins in the Dinaric Karst. Boreholes and gravimetric measurements show thick Neogene loose sediments and the rocky bottom below the sea level - real cryptodepressions. The sediments make parts of a large plain that subsided at the end of the low Pliocene. The recent seismic activity in this area proves the ongoing tectonic process. The deepest (more than 100 m) and the smallest polje in the Slovenian Dinaric karst, Globodol is a dry polje in the piezometric level. Quaternary subsidence of the bottom is the only reasonable explanation of its genesis. On Planinsko polje there are signs ob suballuvial corrosion and the indicators of the Holocene tectonic subsidence. Four poljes in the Ravni kotari (Dalmatia) are shallow basins in the first stage of development. They prove the process of the bottom levelling below the shallow cover of alluvial sediments. An extremely deep small basin is about 450 m deep Red Lake (Hercegovina) and small basins at Črnomelj and Kočevje (Slovenia), 300 m and 100 m deep below the sea level.

The relief of Bela Krajina and Semiska Reber in southeastern Slovenia is mainly a consequence of post Late Miocene tectonic movements and karstic, mostly subsoil, erosion. In the lower half of the slope at Vrtaca in the northwestern part of Bela Krajina, 1.3 km northeast of the center of Semic and 15 to 25 meters above the surroundings, a 250-meter long and about 150-meter wide lateral ridge rises at an inclination of 8°. The formation of the medium-sized relief between the elevated lateral ridge and the lower elongated side depressions is most probably to a large extent the consequence of differences in the rock fissuring and the varying intensity of hundreds of thousands of years lasting corrosion related to it. Traces of subsoil formation are the prevailing feature found on hundreds of rock ribs (i.e., subsoil rock formations that are not cone-shaped like teeth but rather elongated with their longer axes largely parallel to the dip of the surface) dissecting the surface area of one of the vineyard plots on the rocky lateral ridge. This indicates they were relatively recently exposed, as a consequence of human activity when soil was removed from an abandoned plot.

the surface and maintained that as our regular drill. Partly this was governed by our ability to suppress the receiver after the transmitter pulse, but also the geometry of the beam and the height above the surface governs the internal layering that you can see within the ice mass. If you are low, the echo return from oblique angles is of short duration and you have a better chance of seeing weak layering effects in the ice than if you are, say, 1000 m above the surface. This point showed up in some of Professor Gudmandsen's slides, when he was 20 metres above the surface he had a distinct bottom echo but when he was 1000 m above the surface, the bottom almost merged into the noise.