Geološko pot v Kobilji curek odlikuje izjemna geološka pestrost, na kratki razdalji se zamenja šest različnih kamnin:
1. PEŠČENJAK, MULJEVEC /sandstone, mudstone
Vijolično rdeča barva sedimentnih kamnin in tal je največkrat posledica primesi železa oziroma železovih mineralov, predvsem hematita. Plasti sedimentnih kamnin so bile v času nastajanja horizontalne, sedaj pa le redko kje opazujemo vodoravne plasti. Nagnjenost plasti je posledica tektonskih procesov, ob katerih so se plasti nagibale, gubale in prelamljale.
The violet red colour comes most often from iron and iron minerals, mostly hematite, that are mixed within the rocs. The layers of sedimentary rocks were in horizontal position when they were formed but now we can only rarely see horizontal layers. Tilting layers are a result of tectonic processes that leaned, folded and fractured horizontal layers.
2. TUF / tuff, volcanic rock
Trdoto in ostrino tufa so poznali že v starejši kameni dobi. Tedaj so iz tufa izdelovali različna primitivna orodja: strgala, nože, svedre in drugo. Poleg roženca je tuf najpogostejša kamnina, ki jo je pračlovek uporabljal na našem prostoru.
Because of this characteristics it was used by people already in the Early Stone Age. It was used for tools, such as scrapers, knives, drills and others. Tuff and chert were the two most often used stones by early men in the area.
3. ČRNI PLASTNAT APNENEC /layered limestone in
5. fosili / fossils,
Temno siva ali črna barva apnenca (in tudi dolomita) je običajno posledica prisotnosti humuznih snovi ali bitumna. Že majhna količina (manj kot 1 %) drobno razpršenega bitumna lahko kamnino obarva povsem črno.
Fosili se običajno ne pojavljajo v vseh plasteh neke kamnine. Pogosteje so le v določenih plasteh, tam pa jih je zelo veliko. Zato je pri iskanju fosilov potrebna vztrajnost.
Limestone or dolomite is coloured dark grey or black when it contains traces of bitumen. Small quantities of bitumen (less then 1 %) of well dispersed bitumen can can colour the rock to black.
Fossils are usually not present in all layers of a rock. They are mostly found in a single layer but then in larger quantities. That is why we have to be persistent when looking for fossils.
4. beli neplastnat apnenec / massive limestone
Apnenec je sestavljen iz kalcijevega karbonata, bolj natančno iz minerala kalcita, kemično CaCO3. Raztaplja ga ogljikova kislina, ki nastaja ob reakciji deževnice z ogljikovim dioksidom. Plastnati apnenec se lepo kroji v ravne plasti, površina neplastnatega pa je nepravilno oblikovana.
Limestone is composed of calcium carbonate, more precisely from the mineral calcite (CaCO3). It is soluble in carbonic acid that is formed when rainwater reacts with carbon dioxide. Layered limestone is arranged in level layers, while the surface of masive limestone is irregular.
6. RIMSKI ZAPORNI ZID (Claustra Alpium Iuliarum) / roman deffence system
Neplastnat apnenec, ki ga povezuje malta, je glavni gradbeni material, ki so ga Rimljani v 4. stoletju uporabili za gradnjo zapor, ki bi rimski imperij ubranile pred vdori barbarskih plemen. V bližini je stal obrambni stolp.
Nonlayered limestone plestered with with mortar was the main construction materiale that Romans used for their defence walls that were supposed to protect the Roman Empire against Barbarian tribes. The defence tower stood nearby.
7. DOLOMIT / dolomite
Dolomit je tako mineral kot tudi kamnina, sestavljena iz minerala dolomita, ki je kemično kalcijevo magnezijev karbonat. Kemična razlika med apnencem in dolomitom je razlog, da solna (klorovodikova) kislina apnenec topi, dolomita pa ne. Za preizkus uporabljamo razredčeno 10% solno kislino.
Dolomite is a mineral and a rockof the same name composed of calcium magnesium carbonate. This chemical difference is the reason why hydrochloric acid dissolves limestone but not dolomite. In field tests, a diluted 10% hydrocloric acid is used.
8. SLAP KOBILJI CUREK / Kobilji curek waterfall
Za gozdni rezervat Kobilji curek (3ha) velja poseben varstveni režim. Na koncu grape je slap Kobilji curek, najvišji slap na Dolenjskem. Slap ima dve stopnji, vsaka je visoka okoli 15 m. V celoti pada preko apnenčastega skalnega roba, ki je nastal ob prelomu. V bližini je nahajališče slovenskega endemita kranjskega jegliča Primula carniolica. Cveti od aprila oziroma maja do junija.
The Kobilji curek forest reserve (3ha) is protected by special regulations. At the and of the valley, there is the Kobilji curek waterfall, the highest waterfall in Dolenjska region. The waterfall has two steps, each about 15 m. tha water falls over limestone rock edge that was formed when rock layers ruptured. Nearby we can find the Slovenian endemic flower, Carniolan Primrose (Primula carniolica). It flowers from April -May to June.
9. LEHNJAK / tufa
Lehnjak največkrat nastaja ob izvirih. Kemično je lehnjak kalcijev karbonat, enako kot apnenec. Nastajanje lehnjaka je obraten proces od raztapljanja apnenca. Za nastanek lehnjaka so običajno potrebne vodne rastline, ki spreminjajo kemijsko ravnotežje v izvirski vodi in tako omogočijo izločanje lehnjaka.
Tufa forms mostly around water springs. Chemically it is calcium carbonate, the same as limestone. Its formation is a reverse chemical process of limestone dissolution. Usually it needs vegetation to form , because plants change chemical balance in the water and cause tufa to form.
10. MEANDER / meander
Meander je rečni zavoj oziroma okljuk. Voda v potoku ali reki ima vedno večjo hitrost in moč na zunanji strani meandra, zato tam odnaša kamninski material in erodira brežino. Na notranji strani meandra pa ima potok manjšo moč, zato tam odlaga svoje naplavine v obliki meandrskega nasipa.
Meander is a river bend. The water is always faster and stronger on the outer side of a meander, that is why it erodes the river bank. The stream is weaker on the inner side, that is why it deposits its sediments here.