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Geološki časovni stroj - Geological time machine Multi-cache

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Ta multicache je posvečen znanstveni vedi geologiji in značilnim kamninam, ki jih lahko najdemo v Slovenij. Upam, da bo ta multicache dovolj zanimiv, da bo komu vzbudil zanimamnje za geologijo ali pa samo razširil geološko znanje.

Geologija je znanstvena veda, ki preučuje Zemljo, njene kamnine, njihov nastanek in fizikalne procese, ki oblikujejo Zemljino površje. Znanstvenik, ki deluje na področju geologije je geolog, vendar je to precej splošen izraz. Geologi delujejo na večih področjih geologije; inženirski geologi pomagajo pri gradnji cest, železnic in hiš, hidrogeologi iščejo in preučujejo nahajališča vode pod zemljo, paleontologi preučujejo fosile, sedimentologi preučujejo sedimentne kamnine, petrologi magmatske, seizmologi potrese,...

Ta multi zaklad vas bo popeljal po mestnih ulicah do zgradb, ki imajo nekatere značilne kamnine, ki jih najdemo v Slovenij. Na sedmih točkah v mestu se boste spopadli z različnimi geološkimi nalogami in ob pravilni rešitvi boste prejeli neko številko. Točke so navedene v zaporedju glede na starost kamnin od najmlajših do najstarejših, zaradi česar vam ni treba slediti temu zaporedju, ampak lahko iskanje prilagodite lokaciji. Ko opravite z vsemi sedmimi nalogami v mestu boste dobljene številke vnesli v koordinate osme točke. Ker se delo geologa velikokrat odvija na terenu, vas bo končna osma točka popeljala iz mesta na lažji teren v naravo. Na osmi točki se boste spopadli še z zadnjo geološko nalogo, kjer boste prejeli koodrinate, ki vam podajo lokacijo skrivališča zaklada.

Za zaklad boste potrebovali najmanj 2,5 uri, poleg tega pa potrebujete tračni meter najmanj dolžine 1 m, kompas in po želji povečevalno steklo za ogled kamnin. Geološkega kladiva ne potrebujete :). Multi zaklad boste opravljali tako v mestu kot tudi v naravi, zato svetujem uporabo primerne obutve. Za lažje razumevanje in opravljanje nalog je priložen še kratek slovarček geoloških izrazov.

Slovarček geoloških izrazov:

Apnenec: karbonatna kamnina, ki jo sestavlja predvsem mineral kalcit. Večinoma nastaja v toplih morjih iz drobnih skeletov morskih organizmov ali se obarja iz vodnih raztopin. Če se skeleti ohranijo, jih prepoznamo kot fosile.

Dolomit: nastane iz apnenca, ko voda obogatena z magnezijem teče skozenj. Magnezij mineral kalcit spremeni v dolomit, ki gradi kamnino z istim imenom.

Globokomorsko okolje: morje globlje od 200 metrov, kamor svetloba ne prodre več. V tem okolju se sedimenti mirno usedajo, saj je temperatura stalna in so prisotni minimalni morski tokovi.

Karbonatna kamnina/karbonat: kemična in/ali biokemična sedimentna kamnina iz minerala kalcita.

Karbonatna platforma: plitvovodno morsko sedimentacijsko okolje, kjer nastajajo apnenci in dolomiti.

Klastične kamnine: mehanske sedimentne kamnine, ki nastenejo s sprijemanjem delcov erodiranih kamnin.

Muljevec: sedimentna klastična kamnina, katere delcev ne vidimo s prostim očesom. Delci so manjši od 63 mikrometrov. Kamnina ki ima delce večje od 2 mikrometrov je meljevec, manjše od 2 mikormetrov pa glinavec.

Peščenjak: klastična kamnina, ki je nastala s sprijetjem peska. Pesek so drobci, ki jih vidimo s prostim očesom in veliki do 2 mm.

Plast: Sediment ali ploščato sedimentno telo, ki ga od spodnje in zgornje kamnine ločita leziki. Lezika je tanka plast preperine ali presledek, ki ločuje dve plasti. Plasti tanjše od 1 cm so lamine, od 1 cm do 10 cm so tanko plastnate, od 10 cm do 30 cm srednje in od 30 cm debelo plastnate. Kamnine brez plasti so masivne.

Plitvomorsko okolje: morje plitvejše od 200 m kamor svetloba še prodre, prisotni so močni morski tokovi, voda pa se še lahko segreje.

Žila: Razpoka, ki jo je zapolnil nek mineral ali kamnina v starejši kamnini.

1. Lehnjah N 46° 03.165 E 014° 30.138

Stojite na križišču med Beethovnovo in Cankarjevo ulico. V severo zahodnem delu križišča je stavba, ki je obdana s ploščami lehnjaka (Slika 1) . Lehnjak ali domači izraz »lahki kamen« je močno porozna in luknjičava karbonatna kamnina (Slika 2). Nastaja s kemijskim izločanjem raztopljenega karbonata v vodi. Karbonat se dostikrat izloča na organskih delcih, zato v njem pogosto najdemo ostanke rastlin. Poznamo tudi sorodno različico travertin, ki je termalnega nastank, saj se karbonat izloča ob izvirih termalne (zelo vroče) vode in le redko vsebuje organske ostanke. V Slovenij travertina ni, med tem ko je lehnjak zelo pogost. Najdemo ga pri Socki, Vranskem, na Gorjancih, v dolini reke Krke, pridobivajo pa ga le na Jezerskem zgolj kot okrasni kamen. Je zelo mlada kamnina, saj je nastajal v obdobju kvartarja (od 2,5 milijona let do današnjega dne) in nastaja še danes.

Stavba ni povsem obdana s ploščami lehnjaka. Ugotovite do vključno katerega nadstropja je popolnonoma obdana z lehnjakovimi ploščami. S številko nadstropja boste dobili novo številko za koordinate osme točke.

Številka nadstropja = A

Slika 1./Picture1.: Plošče lehnjaka na vogalu stavbe./Plates of tufa at the corner of the building.

Slika 2/Picture 2.: Luknje in praznine v lehnjaku./Cavities in tufa.

2. Čizlakit N 46°03.075 E 14°30.071

Stojite pred pročeljem Državnega zbora, ki ga med drugim obdajajo plošče zelenega gabra, ki mu pravimo tudi čizlakit po kraju Cezlak nad Oplotnico na Pohorju. Je magmatska kamnina, ki jo v glavnem sestavlja minerali svetlozelenega avgita, temnozelene rogovače in beli glinenci ter je miocenske starosti (23 do 5 milijonov let). Prepletajo ga bele aplitne in pegmatitne žile (Slika 3. in 4.). Pridobivajo ga v kamnolomu Cezlak II, vendar zaradi majhnih količin le občasno. Lahko bi se reklo, da je kamnina endemit, saj takšnega zelenega različka gabra niso našli še nikjer na svetu. Zaradi tega je cenjen okrasni kamen in zaradi svoje endemičnosti postavljen na pročelju Parlamenta, kot simbol Slovenstva.

Koliko nadstropij na pročelju Državnega zbora je obdanih z zelenimi čizlakitnimi ploščami. Število nadstropij vam bo dalo novo številko za koordinate osme točke.

Število nadstropij = B

Slika 3.(Picture 3.): Zeleni čizlakit z belo aplitno žilo./Green gabbro Čizlakit with white aplitic vein.

Slika 4./Picture 4.: Zeleni čizlakit z belo aplitno žilo./ Green gabbro Čizlakit with white aplitic vein.

3. Granodiorit N 46° 03.207 E 014° 30.250

Stojite pri vodnjaku ob Slovenski cesti. Vodnjak je narejen iz velikega bloka granodiorita, ki ga pri nas najdemo na Pohorju. Granodiorit je magmatska kamnina, ki jo sestavljajo minerali belega plagioklaza, sivega kremena in črnega biotita in rogovače, prepletajo pa ga tudi bele žile aplita in pegmatita (Slika 5.). Je miocenske starosti (23 do 5 milijonov let), in ga pridobivajo v kamnolomu Cezlak I. Zmotno je imenovan kot Pohorski granit ali Pohorski tonalit, saj ima drugačno kemijsko in mineralno sestavo kot granit in tonalit. Je zelo trdna in obstojna kamnina, ki se v veliki meri uporablja v gradbeništvu. Praktično vsi cestni robniki, tlakovci in kocke v mestu so narejene iz granodiorita (Slika 6).

Vaša naloga na tej točki je, da preštejete vse aplitne žile na zahodni stranici bloka (tisti, ki je obrnjene proti Slovenski cesti), ki so širše od 8 centimetrov. Kako izmeriti širino imate podano na Sliki 5. S številko takšnih žil boste dobili novo številko za koordinate osme točke.

Število žil širših od 8 cm = C

Slika 5./Picture 5.: Aplitna žila v granodioritu./Aplitic vein in granodiorite.

Slika 6./Picture 6: Granodioritne kocke, tlakovci in robniki./Granodioritic cubes and flagstones.

4. Rudistni apnenec N 46° 02.960 E 014° 30.248

Stojite pred Univerzo v Ljubljani, kjer je v manjšem parku pred vhodom postavljenih osem doprnih kipov zaslužni univerzitetnih profesorje Univerze v Ljubljani. Kipi stojijo na podstavkih zgornje krednega rudistnega apnenca. Gre za apnenec zgornje kredne starosti (99 do 65 milijonov let), ki se je odlagal na karbonatni platformi v plitvem tropskem morju (nekaj podobnega današnjim Bahamom). Značilnost tega apnenca je, da ga sestavljajo rudistne školjke, ki so značilne za obdobje zgornje krede in so v kamnini dobro vidne (Slika 7.). Rudistne školjke so bile školjke, ki so imel dve asimetrični loputi, eno zelo podolgovato in drugo, ki je delovala kot pokrov. Njihova značilnost je, da so lahko živele v velikih skupinah, ki jim rečemo tudi trate (Slika 8.). Izumrle so skupaj z dinozavri pred 65 milijoni let, na meji med obdobjema krede in terciarja. V Sloveniji najdemo rudistne apnence na Krasu, kjer sta ena od kamnolomov apneneca tega tipa Lipica I in Lipica II. Tu pridobivajo dva tipa rudistnega apnenca in sicer rožasti apnenec ali fiorito (preseki rudistnih školjk spominjajo na cvetove rož) in enotni apnenec ali unito. Rožasti ali fiorito apnenec ( Slika 7. in 10.) vsebuje veliko celih lupin rudistnih školjk, med tem ko so v enotnem ali unito lupine zelo zdrobljene in zelo majhne. Zaradi tega daje videz enkomerne zrnavosti in enotnosti (Slika 9. in 11.).

Vaša naloga je, da med osmimi podstavki kipov določite koliko podstavkov je iz rožastega ali fiorito apnenca in koliko iz enotnega ali unito apnenca. Pozor, eden od podstvkov je narejen na prehodu iz rožastega v enotni apnenc (ena stranica ima veliko rudistnih školjk, na drugi strani so samo drobci). Ta podstavek izločite iz štetja, da ne bo morebitnih dilem.

Število podstavkov rožastega apnenca = Č

Število podstavkov enotnega apnenca = D

Slika 7./Picture 7.: Presek rudistne školjke (rožasti ali fiorito apnenec)./Rudists seashells in »flower« or fiorito limestone.

Slika 8.: Trata fosilnih rudistnih školj v Omanu.

Slika 9./Picture 9.: Primer drobcev rudistnih školj iz enotnega ali unito apnenca./Example of rudists fragments in »united« or unito limestone.

Slika 10./Picture 10: Podstavek kipa iz rožastega ali fiorito apnenca ./Base of statue made of »flower« or fiorito limestone.

Slika 11./Picture 11.: Podstavek kipa iz enotnega ali unito apnenca. ./Base of statue made of »united« or unito limestone.

5. Ammonitico rosso N 46° 03.148 E 014° 30.389

Stojite pred stavbo Ljudske posojilnice, ki je grajena v secesijskem slogu. V pritličju je obdana s ploščami iz rdeče kamnine. Kamnina je apnenec, znan kot ammonitico rosso. Kamnino tipa ammonitico rosso najlepše vidimo v Dolini Triglavskih jezer, kjer vsebuje tudi črne gomolje mangana (Slika 12.). Starost kamnine tipa ammonitico rosso sega od srednje jure (170 milijonov let) do konca jure (145 milijonov let). Značilnost tega apnenca je, da se je odlagal v podvodnem okolju na podmorskih planotah, ki so obdane z globljevodnimi okolji. Globina teh planot se ocenjuje do 1000 m globine. Za apnenec tipa ammonitico rosso je značilna rdeča barva (čeprav lahko tudi sivi in zeleni različki), gomoljasta zgradba in ponavadi vsebuje veliko fosilnih ostankov amonitov. Amoniti so bil mehkužci, ki so živeli v obdobju od devona (400 milijonov let) in so izumrli skupaj z dinozavri ob koncu obdobja krede pred 65 milijoni leti. So sorodniki današnjih lignjev in hobotnic.

Slika 12./Picture 12.: Primer apnenca ammonitico rosso z gomolji mangana v Dolini Triglaskih jezer./Example of the ammonitico rosso limestone with manganese nodules in Triglav valley.

Vaša naloga na tej točki je, da poiščete fosil amonita, ki ga vidite na Sliki 13 in približno izmerite koliko visoko nad tlemi se nahaja. Ob pravilnem odgovoru boste dobili novo številko za koordinate osme točke.

Slika 13./Picture 13.: Amonit, ki ga iščete./Ammonite that you are looking fore.

Višina amonita od tal:

a) 0,5m.........4

b) 2,5m.........0

c) 1m............6

d) 3m............3

Pravilni odgovor = E

6. Litiotidni apnenec N 46° 03.013 E 014° 30.258

Stojite pred kapucinskim vodnjakom na Kongresnem trgu. Vrč (Slika 14) v katerega pada voda je narejen iz temno sivega litiotidnega apnenca. Apnenec je spodnje jurske starosti iz obdobja liasa (199 do 175 milijonov let). Bele več 10 cm dolge lise, ki so vidne v tem apnencu iz katerega je vrč, so fosilni ostanki velikih litiotidnih školjk, ki so se združevale na plitvih karbonatnih platformah toplih tropskih morij. Litiotidni apnenc je znan tudi po imenu Podpeški apnenec ali Podpečan, saj so ga v kamnolomu v Podpeči na Ljubljanskem barju pridobivali že Rimljani. Kot gradbeni in okrasni kamen ga je uporabljal tudi arhitekt Jože Plečnik, kar lahko vidimo na pročeljih Narodne in univerzitetne knjižnice ter Gimnazije Jožeta Plečnika. Litiotidni apnenec si lahko tudi ogledate pred Magistratom.

Vaša naloga na tej točki je, da ugotovite ali je vrč iz katerega priteka voda tudi tako bogat z litiotidnimi školjkami kot vrč v katerega voda pada. Prav tako primerjejte stebra in vrč v katerega voda pada. Ob pravilnem odgovoru boste dobili novo številko za koordinate osme točke.

a) Oba vrča in stebri so bogati z litiotidnimi školjkami.....7

b) Le vrč v katerega pada voda je bogat z litiotidnimi školkami..... 8

c) Oba vrča sta bogata z litiotidnimi školjkami, stebra nista......9

Pravilni odgovor = F

Slika 14./Picture 14..: Vrč iz litiotidnega apnenca spodnje jurske starosti v katerega pada voda./Sink made of lithiotidic limestone in which water falls.

7. Črn ladinijski apnenec N 46° 02.770 E 014° 30.422

Stojite pred vhodom v cerkev Svetega Jakoba. Obok vhoda je zgrajen iz črnega apnenca z belimi kalcitnimi žilami, ki je najverjetneje ladinijske starosti (srednji trias, 237 do 228 milijonov let). Apnenec tega tipa so pridobivali v kamnolomu Podrečje in Imovica pri Domžalah in na Ravniku zahodno od Toškega čela pri Ljubljani.

Točno pred vhodom v cerkev (označeno s puščico, Slika 15) je v kamnini vidna cona striga. Cona striga v kamnini nastane takrat, ko v kamnini delujeta dve enako veliki, vendar nasprotno usmerjeni sili (Slika 16. in 17.). Če sili delujeta dovolj dolgo kamnina lahko poči ali se razlomi. Cone striga zaradi tega pogosto najdemo tam, kjer se v kamnini dogajajo deformacije, recimo v bližini prelomov. Če se napetost sile ustavi preden kamnina poči, v njej nastanejo prostori, ki jih lahko pogosto zapolnijo minerali, v tem primeru kalcit. Te prostori so značilne zavite (S) oblike in si pogosto sledijo drug za drugim v smeri delovanja sile napetosti. Na podlagi oblike zavitosti se lahko ugotovi smer delovanja sile napetosti (Slika 16. in 17.).

Vaša naloga je, da pred vhodom poiščete cono striga, ki je vidna na sliki 16. in 17. in s pomočjo kompasa določite smer (azimut) v kateri je delovala sila napetosti v kamnini*. Ob pravilnem odgovoru boste dobili novo številko za koordinato končnega zaklada.

Ali je sila napetosti delovala v smeri:

a) S-J.........11

b) SZ-JV.........4

c) V-Z............ 10

*Cona striga v tem primeru je seveda v kamniti plošči, ki je bila izkopana v kamnolomu in prenešena na to mesto. To pomeni, da trenutna smer cone striga seveda ni v naravni poziciji.

Pravilni odgovor = G

Slika 15./Picture 15.: Vhod v cerkev Svetega Jakoba. Puščica označuje kje pred vhodom se nahaja cona striga. /Entrance to St. James's Parish. The arrow indicates the location of shear zone in front of the entrance.

Slika 16./Picture 16.: Cona striga pred vhodom v cerkev. Puščici označujeta smer delovanja sil./Shear zone in front of the entrance in to the curch. The two arrows indicates the directon of two forces.

Slika 17./Picture 17.: Cona striga od blizu. Puščici označujeta smer delovanja sil./ Shear zone in front of the entrance in to the curch. The two arrows indicates the directon of two forces

8. Permokarbonski peščenjaki, meljevci in glinavci, N 46 EC.BFF E 14 Č(G-A) E(D-A)E

Zaklad se nahaja na enih od najstarejših kamnin v Sloveniji in sicer v permokarbonskih peščenjakih, meljevcih in glinavcih (starost 300 milijonov let, na meji med karbonom in permom). Permokarbonske kamnine tega tipa najdemo v oklici Ljubljane, med drugim na Rožniku, Grajskem griču in Golovcu. Peščenjaki, meljevci in glinavci so klastične sedimentne kamnine, ki jih gradijo klasti peska, melja in gline. Slednji so se odlagali na ustju rek v zelo močvirnem okolju v obdobju karbona in perma. Sčasoma so se te sedimenti sprijeli in nastale so kamnine, ki jih lahko vidimo v tankih do srednje debelih plasteh (Slika 18.). Med temi plastmi lahko najdemo bele žile kremena. Od kalcitnih žil, ki smo jih spoznali pri črnem ladinijskem apnencu jih ločimo po njihovi trdoti in odpornosti na kislino (Slika 19). Kremen je bistveno trši, saj lahko opraska jeklo na nožu ali kladivu, med tem ko je kalcit mehkejši in tega ne naredi. Kalcit se tudi za razliko od kremena topi že pri zelo nizkih koncentracijah kisline.

Do osme točke vas pripeljejo koordinate, ki ste jih dobili, če ste pravilno opravili prejšnjih sedem nalog. Na tej točki se boste spopadli z zadnjo nalogo. Na koordinatah osme točke se nahaja škatla srednje velikosti z različnimi kamni v njej, na vsakem kamnu so napisane različne koordinate. Kamni so z različnih koncev Slovenije, le eden je z griča kjer se nahajata osma točka in zaklad. Vaša naloga je, da ugotovite kateri kamen v škatli to je in dobili boste pravilne koordinate do zaklada. Da uspešno opravite zadnjo nalogo morate skrbno opazovati kamnine na griču, kjer se nahajate. Pozor, ne opazujte kamnin, ki ležijo neposredno na poti, ampak le tiste, ki so v naravi. Po opravljeni nalogi vrnite kamne v škatlo, njo pa na najdeno mesto.

Sliaka 18./Picture 18.: Plasti permo-karbonskega peščenjaka na Rožniku./Permian Carbone layers on Rožnik hill.

Slika 19./Picture 19.: Beli žili kremena označeni s puščicama v permo-karbonskem peščenjaku na Rožniku./White quartz vains in the picture marked whit arrows Rožnik hill.

Koordinate osme točke N 46 EC.BFF E 14 Č(G-A) E(D-A)E

A=

B=

C=

Č=

D=

E=

F=

G=

Test pravilnosti: A+B+C+Č+D+E+F+G=33

Viri in literatura

ROŽIČ, Boštjan, ŽVAB ROŽIČ, Petra, RMAN, Nina. Tihe priče burne preteklosti : kamnine Julijskih Alp. Planinski vestnik, ISSN 0350-4344, jun. 2014, letn. 114, [št.] 6, str. 7-12, ilustr. [COBISS.SI-ID 54998882]

MIRTIČ, Breda (avtor, urednik), MLADENOVIČ, Ana, RAMOVŠ, Anton, SENEGAČNIK, Andreja, VESEL, Jože, VIŽINTIN, Nada. Slovenski naravni kamen. Ljubljana: Geološki zavod Slovenije: Zavod za gradbeništvo Slovenije: Naravoslovnotehniška fakulteta, Oddelek za geologijo, [1999]. 131 str., ilustr. ISBN 961-6101-05-6. [COBISS.SI-ID98459648 ]

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This multicache is dedicated to the scientific discipline of Geology and the characteristic rocks that can be found in Slovenia. I hope that this multicache will expand the visitor’s geological knowledge or even inspire some to take a greater interest in this science.

Geology is a scientific discipline that studies the Earth, it’s rocks, their formation and the physical processes that form the Earth’s surface. A scientist working in the field of geology is called a geologist and he can work in numerous fields that belong within the discipline: engineering geologists are essential in all types of construction, seismologists study earthquakes, hydrogeologists are searching for and studying aquifers, paleontologists are studying fossils, sedimentologist are interested in sedimentary rocks, while petrologists are focused in magmatic rocks and the list goes on, …

This multicache will take you on Ljubljana’s city streets to buildings made out of some of the characteristic rocks that we can find through Slovenia. You will face different geological tasks on seven different locations in the city. Each correct solution of a task will give you a number. The locations in the description are placed in order by the ages of the rock but you can visit them in an arbitrary order. After you solve all the seven tasks in the city you will obtain the coordinates of the eight location. Because geologists often need to include field work into their study you will have to go out of the city into the nature where you will face the last geological task that will give you the coordinates of hidden cache.

You will need at least 2.5 h to find this cache. You will also have to include some equipment: tape measure (at least 1m), compass and optionally a magnifying glass to look at the rocks. You won’t need a geological hammer  You will search for the cache in the city and in nature so wear appropriate footwear. For easier comprehension and solving the tasks take a look at the vocabulary of geological expressions below.

The vocabulary of geological expressions:

Limestone: A carbonate rock made predominantly out of the mineral calcite. It is mostly formed in warm seas from skeletons and skeletal fragments of different sea organisms. If the skeletons are preserved in the sedimentary record we can see them as fossils. Limestone can also precipitate out of calcium rich solutions.

Dolomite: It is formed out of limestone after a magnesium rich solution runs through it. Magnesium changes the calcite mineral into a dolomite mineral which bears the same name as the rock it composes.

Deep-sea environment: The expression marks a sea environment deeper than 200 m which is the maximum depth of sun light penetration. Sediments in this environment have a constant sedimentation rate because the temperatures are constant so underwater currents that could disturb the deposition of sediment cannot occur.

Carbonate rock: Chemical and/or biochemical sediment rock made out of the mineral calcite.

Carbonate platform: Shallow-water marine sedimentation environment where limestones and dolomites are formed.

Clastic rocks: Mechanical sediment rocks which form with adhesion of previously eroded rock fragments.

Mudrock: A sedimentary clastic rocks which particles we cannot see with the naked eye because they are smaller than 63 micrometers. It is subdivided into siltstone (particles larger than 2 micrometers) and claystone (particles smaller than 2 micrometers).

Sandstone: A sedimentary clastic rock formed with adhesion of sand particles which are smaller than 2 mm and can be seen with the naked eye.

Stratum: A layer of sedimentary rock that was deposited in a certain period of time and has characteristics that make it distinguishable from other surrounding layers. Layers thinner than 1 cm are called laminae, thin-bedded layers are 1 – 10 cm thick and thick-bedded layers are thicker than 30 cm. Rocks in which we cannot see stratum are called massive rocks.

Shallow-sea environment: Sea shallower than 200 m in which the sun light can penetrate, change the temperature of water and create underwater currents that can disturb the sedimentation.

Vein: A crack in an older rock that was filled by a mineral or a younger (usually magmatic) rock.

1. Tufa N 46° 03.165 E 014° 30.138

Building on the NW corner of the crossroad has a tufa plates. Tufa (Picture 1.) is a sedimentary rock formed by the precipitation or deposition of calcium carbonate in cold water. It has many cavities (Picture 2.) and there are often organic particles in it such as leafs, brunches and roots. A similar rock is travertine which participates in thermal waters and usually doesn’t have any organic remains. There is no travertine in Slovenia, but a lot of tufa in Dolenjska, especially in river Krka valley. Tufa is used as decorative rock and it is acquire in a quarry near Jezersko. It is very young rock only 2,5 million years old.

Building is not covered in tufa plates all over its frontage. Your task is to find out up to which floor it is covered completely. Thu number of floor will give you a number for the coordinates of stage eight.

Number of floor = A

2. Green gabbro N 46°03.075 E 14°30.071

You are standing in front of Slovenian parliament which at its frontage has plates of green magmatic gabbro at each floor. This green gabbro is called Čizlakit after its place of origin Cezlak in Pohorje mountains. It has light green augite, dark green hornblende and white feldspar white pegmatite an aplitic veins (Pictures 3. and 4.). It is Miocene age (23 to 5 million years old). This green gabbro is unique to Slovenia since it has not been found anywhere in the world. Because of its colour it is used as a decorative stone and due to its Slovenia uniqueness it is placed on parliament to represent Slovenia.

Your task is to count on how many floors the green gabbro is placed. Thu number of floor will give you a number for the coordinates of stage eight.

Number of floor = B

3. Granodiorite N 46° 03.207 E 014° 30.250

You are standing at a fountain at Slovenska street. Big block in fountain is made of Miocene (23 to 5 million years) granodiorite, that is acquire in Pohorje mountains. It has white plagioclase, grey quartz, and black hornblende minerals whit white pegmatite an aplitic veins (Picture 5.). This granodiorite is often used as a building rock for pavements and flagstones in Ljubljana for its hardness and durability (Picture 6.).

Your task is to count all aplitic and pegmatite veins on the western side of the block (the side that is facing Slovenska street) that are wider than 8 cm. How to measure width of veins is shown in the Picture 5. Thu number of veins will give you a number for the coordinates of stage eight.

Number of veins wider than 8 cm = C

4. Limestone with rudists seashells N 46° 02.960 E 014° 30.248

You are standing in a small park in front of University of Ljubljana. There are eight statues with portraits of important Slovenian professors. The bases of statues are made of upper Cretaceous limestone (99 to 65 million years) that has rudists seashells (Picture 7.). This limestone is fund in Kras region in Slovenia and there are two basic types of this limestone. First is “flower” limestone or fiorito (Pictures 7. and 10.) and the other is “united” or unito limestone (Pictures 9. and 11.). The difference between them is in rudits seashells. In “flower” or unito limestone the seashells are not fragmented but are whole pieces. The seashells are in a shape of flowers hence the name “flower” limestone. The “united” or unito limestone has very small fragments of rudists seashells hence the name “united” or unito.

Your task is to count all the bases that are made of “flower” or fiorit limestone an all the bases that are mad of “united” or unito limestone. Attention! One base is made of contact between both types, one side is fiorito and one is unit. To avoid any dilemma you do not need to count this base to any one of the two types. Thu number of bases of both types of limestone will give you a number for the coordinates of stage eight

Number of bases made of “flower” or fiorito limestone = Č

Number of bases made of “united” or unito limestone = D

5. Ammonitico rosso N 46° 03.148 E 014° 30.389

You are standing in front of People's Loan Bank made in Secession stile. The facade has plates of red limestone known as Ammonico rosso (middle to upper Jurassic, 170 to 145 million years). This type of rock is best seen in Triglav valley where it also has manganese nodules (Picture 12.). This type of limestone often has fossils of ammonites, distant relatives of octopuses that lived from Devonian age (400 million years) up to end of Cretaceous age (65 million years ago) and extinct with dinosaurs.

In the Picture 13 there is an example of ammonite that you can find in one of the plates. Your task is to find this exact ammonite and measure how high above the ground is placed. At the right answer you will get a number for the coordinates of stage eight.

Height of ammonite above the ground:

a) 0,5m.........4

b) 2,5m.........0

c) 1m............6

d) 3m............3

Correct answer = E

6. Lithiotidic limestone N 46° 03.0135 E 014° 30.258

You are standing in front of Capuchine fountain made of lithiotidic limestone. Limestone is upper Jurassic age (199 to 175 million years) and it has more than 10 cm long white spots (Picture 14.).. This are lithiotide seashells that lived in upper Jurassic period in shallow and warm environment such as now days Bahamas. Limestone of this type is acquire in a quarry in Podpeč near Ljubljana and it has been used as a decorative stone by Slovene architect Jože Plečnik in many of his buildings such as National and University Library.

The sink in which water falls is rich with lithiotide seashells (Picture 14.). Are the pillars and the amphorea behind it also as rich with lithiotide seashells as the sink? At the right answer you will get a number for the coordinates of stage eight.

a) Amphorea and pillars are as rich with lithiotides as the sink.....7

b) Only the sink is rich with lithiotide seashells..... 8

c) The sink and amphorea are rich with lithiotide seashells but not the pillars......9

Correct answer = F

7. Black Ladinian limestone N 46° 02.770 E 014° 30.422

You are standing in front of church of Saint James’s Parish. The entrance in church is made of black limestone with white calcium carbonate veins , probably Ladinian age (Middle Triassic, 237 to 228 million years ago). In front of the door (marked with an arrow in the Picture 15.) on the ground you can see a shear zone. This is a structure within which the rock has gone under intense deformation. Usually the force is implied in two different directions ((Pictures 16. and 17.). If the forces are present long enough, the rock breaks. If it does not, the force leaves cavities in distinct shape (S) that are usually filled with minerals, in this case calcium carbonate. Based on the shape of cavities we can determine direction of the shear zone.

Your task is to find shear zone in the Pictures 16. and 17. and with a compass determine the azimuth in which the force was applied*. At the right answer you will get a number for the coordinates of stage eight.

The force was applied in the direction:

a) N_S.........11

b) NW-SE.........4

c)E-W............ 10

*Shear zone in this case is in a plate that was transported from the quarry. The real direction in nature was of course different

Correct answer = G

8. Permocarbonian sandstone, siltstone and claystone N 46 EC.BFF E 14 Č(G-A) E(D-A)E

The cache is located on one of the oldest Slovenian rocks, the permocarboninan sandstones, siltstones and claystones (age of 300 milion years, the boundary between Carboniferous and Permian). We can find this rocks near Ljubljana on the hills od Rožnik, Castle hill and on Golovec.

You can reach the eight stage if you have the coordinates from the previously seven stages. This is the last stage with the final task that you have to save to find the location of the cache. The eight stage is the location of a middle sized box which contains different rocks with different coordinates. The rocks are gathered from different locations all over Slovenia, only one of them originates from the hill you are standing on and which is also the macrolocation of the cache. Your mission is to carefully observe the outcrops of the hill and find out which rock in the box originates from it. The coordinates on the rock will lead you to the location of the cache.

After you find the right rock please return all the rocks and the box on the appropriate location.

Additional Hints (Decrypt)

Trbybtv vmqrynwb iegvab gnxeng, xb všprwb ansgb, cbqmrzab ibqb nyv xnzavar tybobxb cbq mrzywb. / Trbybtvfgf znxr oberubyrf jura gurl ner frnepuvat sbe bvy, haqretebhaq jngre be ebpxf qrrc haqre tebhaq.

Decryption Key

A|B|C|D|E|F|G|H|I|J|K|L|M
-------------------------
N|O|P|Q|R|S|T|U|V|W|X|Y|Z

(letter above equals below, and vice versa)