Crvenica u području Kvarnera: geomorfološki uvjeti postanka

Red soil or terra rossa is the most common soil type developed on carbonate rocks in the Kvarner area. In most cases, terra rossa has polygenetic origin and was formed by mixing of insoluble residue of carbonate rocks with weathered and eroded loess and flysch sediments. Climatic and glacioeustatic changes and tectonic movements during Quaternary have influenced recent position of terra rossa and its mineralogical composition. The recent position of terra rossa is a consequence of erosion. In the areas where tectonic movements were more pronounced, because of slope erosion and resedimentation-colluviation processes terra rossa is found in isolated depressions in the form of thicker depostits. Examples are northern part of Cres island and southern slopes of the Učka mountain. In the areas where tectonic movements were less pronounced terra rossa covers larger areas in the form of thinner deposits. An example is the western part of the island Krk.Crvenica ili terra rossa je najzastupljeniji pedološki tip odnosno pokrivač na karbonatnim stijenama kvarnerskog područja. Crvenica je najčešće poligenetske prirode i tada je nastala miješanjem netopljivih ostataka karbonatnih stijena s trošnim i erodiranim naslagama lesa i fliša. Na minerološki sastav i današnji položaj crvenice utjecale su klimatske i glacioeustatičke promjene, kao i tektonski pokreti tijekom kvartara. Današnji raspored crvenice posljedica je erozije. Tamo gdje su tektonski pokreti bili izraženi, terra rossa se zbog erozije padina i resedimentiranja-koluvacije nalazi u izoliranim depresijama u obliku debljih nakupina. Primjeri su sjeverni dio otoka Cresa i padine južne Učke. Tamo gdje su tektonski pokreti bili slabo izraženi, terra rossa je male debljine, ali pokriva velike površine. Primjer je zapadni dio otoka Krka

Geomorfološki indikatori promjene morske razine tijekom gornjeg pleistocena (virma) i holocena u području Kvarnera

This paper presents the data on the influence oft he sea level change during the last 150000 years on the morphogenetic events int he Kvarner region (the north eastern part of the Adriatic Sea). Some geomorphologic indicators with possible influences on sea level changes, such as sea bottom morphology, the submarine zone sediments disposition, karsification depths, cave development depths and others have been analysed. The present land, coastal, and submarine relief in the Kvarner region was formed as a consequence of tectonic movements, different lithology, climatic changes, and sea level fluctuations during the late geological history, but also because of the erosional amd accumulation processes caused by these changes. The remnants of the older morphogenetic phases have mostly been destroyed. The riverbeds were cut into the bedrock to -60 m beacuse of the sea level fall during the Würm. The carbonate rocks were karstified 70 m below the recent sea level. The present sediment distribution in the Kvarner submarine zone is a consequence of several morphogentic phases correlated with the sea level changes during the Late Pleistocene. Due to much lower sea level in some periods of the Würm glacial the connections between the Rijeka Bay, Kvarnerić, Vinodol and Velebit channels and the open Adriatic were reduced or even interrupted. In the depressions of the Rijeka Bay, Vinodol, and Velebit Channel during periods of lower sea level, lakes could be formed and only the Kvarnerić Bay could have remained connected to the Central Adriatic basin. In this period the Cres – Lošinj archipelago elevations were a morphologic barrier that divided open Adriatic sedimentation zone from the relatively isolated Kvarner region. Therefore the sea bottom is considerably deeper eastern (-70 to -90 m) than western of the Cres and Lošinj islands (-40 to -50 m). That is also the reason for the bottom sediments western of Cres – Lošinj archipelago to be mainly sandy. while those on eastern side to be more silty. Due to the lower sea level, the terrigenous material deposition occurred deeper and farther away from the present coastline, in areas where terrigenous influence is neglibible today. According to the traces of the ancient riverbeds in the Kvarnerić region the sea level at the peak of Würm was more than 100 m below present position. Marine terraces on -45 m and tidal notches on -19 m might have been formed during periods of the slower sea level rise or even its temporal stagnation during the Würm-Holecene transgression.U radu se prikazuje utjecaj promjene morske razine tijekom posljednjih 150 000 godina na morfogenetska zbivanja u području Kvarnera (sjeveroistočni dio Jadranskog mora). Analizirani su oni geomorfološki indikatori koji bi mogli ukazivati na promjene morske razine: morfologija dna, raspored dna, raspored sedimenata u podmorju, dubine okršavanja, dubine razvoja spilja i slično. Recentno kopno, obalni i podmorski reljef u području Kvarnera su posljedica tektonskih pokreta, različitog litološkog sastava, klimatskih promjena i fluktuacije morske razine tijekom mlađe geološke prošlosti, ali također i posljedica erozijskih i akumulacijskih procesa prouzročenih tim promjenama. Tragovi starijih morfogenetskih etapa uglavnom su uništeni. Zbog snižavanja morske razine tijekom virma korita vodotoka usječena su u podlogu do -60 m. Karbonatne stijene su okršene 70 m ispod današnje razine mora. Današnji raspored sedimenata u podmorju Kvarnera posljedica je nekoliko morfogenetskih etapa sukladnih promjenama morske razine tijekom gornjeg pleistocena. Tijekom niže razine mora u nekim razdobljima virmskog glacijala veze između Riječkog zaljeva, Kvarnerića i Vinodolskog i Vinodolskog kanala i otvorenog Jadrana bile su reducirane ili čak prekinute. U razdobljima niže morske razine u depresijama Riječkog zaljeva, Vinodolskog i Vinodolskog kanala mogla su preostati jezera, a jedino je Kvarnerić mogao ostati povezan s morskim bazenom srednjeg Jadrana. U tom razdoblju uzvišenja Cresko-lošinjskog otočja bila su morfološka barijera koja je odvajala sedimentaciju u zoni otvorenog Jadrana od relativno izoliranog akvatorija Kvarnera. Zato su dubine mora znatno veće istočno od Cresa i Lošinja (-70 do -90 m) od onih na zapadu (-40 do -50 m), te su sedimenti zapadno od Cresko-lošinjskog arhipelaga pretežno pjeskoviti, a istočno više muljeviti. Zbog obalne linije koja je bila niža i dalje od današnje, taloženje krupnozrnatih terigenih sedimenata zbivalo se dublje i dalje od recentne obalne crte, u području gdje je utjecaj terigene sedimentacije danas zanemariv. sudeći prema usječenim dolinama vodotoka kojim su tekli do bazena Kvarnerića, more je na vrhuncu virma bilo preko 100 m niže. Tragovi marinskih terasa na -45 m i plimskih potkapina na -19 m mogli bi biti posljedica sporijeg rasta ili čak stagnacije morske razine tijekom virmsko-holocenske transgresije

Morphological evolution of the Rijeka Bay: The influence of the climatic and glacioeustatic changes

Ovaj rad razmatra obalno područje i podmorje Riječkog zaljeva. Recentni reljef u području Riječkog zaljeva posljedica je tektonskih pokreta, promjena klime i morske razine tijekom bliže geološke prošlosti, a također i egzogenetskih procesa. Klimatske promjene i glacioeustatičke oscilacije mora tijekom posljednih 700 000 godina snažno su utjecale na promjenu reljefa, pa su uništeni tragovi starijih morfogenetskih etapa. Na dnu Riječkog zaljeva vjerojatno su bila izolirana jezera na vrhuncu virmske regresije. Krški izvori bili su na kotama znatno nižim od današnjih. Sadašnji položaj i oblik obala koje okružuju Riječki zaljev, posljedica su ponajprije potapanja kopna poradi holocenske transgresije. Rijetki klifovi i uske marinske terase jasni su pokazatelji mladosti obalnog reljefa.This paper analyses the coastal and the submarine zones of the Rijeka Bay, part of the Kvarner Channel area in the North Adriatic. The recent relief of the Rijeka Bay is the result of tectonic movements, climatic and sea level changes, as well as exogenetic processes, occuring during the early geological time. The climatic changes and glacioeustatic sea level oscilations for the past 700 000 years have strongly transformed the relief, and have also destroyed the remains of the older morphogenetic phases. Isolated lakes on the bottom of the Rijeka Bay possibly existed at the peak of Wuerm regression. The riverbeds are deeply cut into the bedrock and karst springs were at much lower levels than today. The recent position of the coastal is a result of the flooding of ancient land areas due to Holocene transgression. The clear indicators of the initial and youthful stage of the coastal relief are the rare cliffs and narrow marine terraces

The Recent Geomorphological Processes in the Area of the Rijeka Bay

U radu su analizirani recentni geomorfološki procesi u obalnom području i podmorju Riječkog zaljeva (sjeverni Jadran). Od kraja posljednjega, virmskog glacijala nastavilo se dizanje razine Jadranskog mora. Zato se mijenjala erozijska baza, energija reljefa te intenzitet erozije i sedimentacije u Riječkom zaljevu. Potopljeni su niži dijelovi brojnih dolina. Uz ušće Rječine te u dijelu Bakarskog zaljeva izraženo je naglo smanjenje dubine dna. U posljednjim tisućljećima postaje naglašenije djelovanje abrazije i bioerozije zbog usporenog rasta morske razine. Nastaju inicijalni oblici abrazijske terase. Abrazijski proces vrlo je selektivan. To zavisi od geološke građe te otpornosti naslaga u litoralnoj zoni, kao i od lokalnih maritimnih prilika. Reljef obalne zone u najvećem dijelu Riječkog zaljeva vrlo je malo izmijenjen djelovanjem mora. Oblik obale prije svega zavisi od lokalnoga strukturno- tektonskog sklopa. Na karbonatnim naslagama u litoralnoj zoni vidljiva je bioerozija. Na padinama Učke i na otoku Cresu bujični tokovi u aktivni, a na sjevernoj primorskoj padini i na otoku Krku uglavnom fosilni.In the paper has been analysed arecent geomorphological processes in coastal area of Rijeka Bay (Northern Adriatic). The rapidly sea-level rise started from the end of last Würm glacial age. Therefore the erosion base, the relief energy and the intensity of the erosion and the sedimentation have chaged. The lower parts of the numerious valleys have been submerged. The rapid sedimentation began near the Rječina River mouth. In the last milleniums there is expressive work of abrasion and bioerosion. The initial forms of the abrasion platform has been formed. The process abrasion is very selective. It primarily depends of geological structure and hardness of rocks in the littoral zone as well as of the local maritime conditions. A relief of the greatest part of the coastal area of Rijeka Bay depends primarily of local srtuctural and tectonic rock fabric. In littoral zone of carbonate composition we have been seen processes of bioerosion. The processes of bioerosion are apparently in the carbonate rocks of littoral zone. The gullies are active on slopes of Učka Mountain and island Cres, but this are mainly fossil in northern coastland and island Krk

On the origin of both a recent and submerged tombolo on Prvić Island in the Kvarner area (Adriatic Sea, Croatia)

This paper analyzes the origins of two tombolos (one recent and another fossil/submerged) on the southwestern coast of Prvić Island, which is located in the Kvarner area in the northeastern part of the Adriatic Sea. A recent tombolo on Cape Pipa was formed by the erosion of Quaternary deposits and Palaeogene siliciclastic rocks. The submerged tombolo is much bigger, clearly visible on the sea bed toward the southwest. The conditions for forming a submerged and recent tombolo have occurred during a slow rise and then stagnation of sea level of the Adriatic Sea in the Holocene. The sea  flooded the fossil tombolo probably in the final part of a period of rapid sea-level rise at the beginning of the Holocene when a large proportion of the Quaternary sediments were eroded. Waves from the northwest (tramuntana) and southeast (jugo) refract and diffract around the tombolo. The nourishment of the beach body happens permanently on both sides of the cape. Accumulated sediments are protected by resistant rocky blocks of breccia on the peak of Cape Pipa, acting as a natural tombolo. Due to the fact that wave directions are perpendicular to the beach coastline, they do not generate longshore currents that would erode sediment in beach bodies around Cape Pipa. Therefore, the recent tombolo is probably stable in the present climatic and oceanographic conditions in the Kvarner area.</p

The Origine and Evolution of Coastal and Submarine Springs in Bakar Bay

Članek obravnava obalne in podmorske izvire v Bakarskem zalivu. Največ izvirov je ob severovzhodni obali zaliva, kjer je najnižji del kontakta med kraškim vodonosnikom in flišem, ki predstavlja hidrogeološko bariero. Študijsko območje obsega obalo med Črnim in Žminjco, kjer voda izteka koncentrirano v nizu kraških izvirov in difuzno na večih območjih. Ob dvigu morske gladine ob koncu pleistocena so nekateri obalni izviri prešli pod gladino, pojavili pa so se tudi novi, višji izviri. Veliko podmorskih izvirov ni poznanih, vendar na njihov obstoj kaže študija vodne bilance. Zaradi velikega hidravličnega gradienta veliko podmorskih izvirov deluje kot vrulje. Mešanje morske in sladke vode v hidravlično nestabilnem območju je vzrok, da je voda iz teh izvirov po večini brakična.The paper presents coastal and submarine springs in Bakar Bay. The northeastern coast of Bakar Bay is abound in springs, since there is the lowest placed contact between large karst aquifer and flysch lithogenetic complex which forms hydrogeological barrier. Studied area is situated between Črno and Žminjca locations, where water flows out in series of concentrated coastal and submarine springs as well as on the places of a diffuse outflow. A rapid raise of sea-level from the end of the Pleistocene changed the hydrogeological conditions so that coastal springs were submerged and new ones, at higher levels appeared. Some of submerged springs continued to throw out water, that is, they started to function as submarine springs (vrulja) due to a strong inflow from the background and high pressures. Some of them were not registered, although according to water balance analyses of wider area, widespread evidences of groundwater outflow could be expected. Their position reflects geological fabric of the area. Groundwaters have intensive flowing gradient. Their flowing out in hydraulically unstable zone have facilitated mixing of sea- water and fresh-water and as a result spring-water is usually brackish

Vulnerability of the Rab island coastline due to sea level rise

U ovom je radu opisana ranjivost obala otoka Raba koja može biti prouzročena prognoziranim porastom razine mora do kraja 21. stoljeća. Opisane su posljedice koju taj prirodni fenomen može prouzročiti. Analizirana su tri scenarija pojava visoke razine mora: kod stagnacije globalne morske razine te kod porasta za 30 i 60 cm. Analize su napravljene na topografskim kartama mjerila 1:5000. Ustanovljene su najugroženije urbanizirane obalne zone: uvala Sv. Eufemija, luka grada Raba, Supetarska Draga i uvala Lopar. Procijenjen je utjecaj povišenja morske razine na djelovanje valova u istraženim obalnim zonama. Kao posljedica porasta morske razine može se očekivati širenje zaslanjenih priobalnih zona na poljoprivredne površine. Vjerojatno će se pojačati marinske erozije na obalama, što će prouzročiti nazadovanje klifova i/ili smanjenje tijela brojnih pjeskovitih žala. Problem može biti i otežana odvodnja s niskih i zaravnjenih dijelova terena kao i rad lokalne oborinske i fekalne kanalizacije. Mogu biti ugroženi i stambeni objekti koji su posljednjih desetljeća izgrađeni u niskim obalnim zonama, kao i neke građevine u srednjovjekovnoj gradskoj jezgri Raba.The paper describes the vulnerability of the Rab island coastline which may be caused by the forecast sea level rising by the end of the 21st century, including the consequences potentially resulting from this natural phenomenon. Three scenarios of high sea level occurrence were analysed: the case of stagnating global sea levels and the cases of sea level rising by 30 and 60 cm. The analyses were conducted on topographic maps in scale 1:5000. The following urbanised coastal zones were established: Sv. Eufemija cove, Port Rab, Supetarska Draga and Lopar cove. The impact of rising sea levels on the wave action in the investigated coastal zones was estimated. Due to rising sea levels, it can be expected that the salinized coastal zones will spread to agricultural land. It is probable that the marine erosion of the coastline will increase, causing a decline in cliffs and/or decrease in the size of numerous sandy beaches. Further problems may consist in a more difficult drainage of low and flat parts of the terrain and the functioning of the local stormwater and faecal sewerage. Additionally, residential buildings constructed in low-lying coastal zones in the recent decades may be threatened as well, including some structures in the medieval historic centre of the town Rab

Vulnerability of the Rab island coastline due to sea level rise

U ovom je radu opisana ranjivost obala otoka Raba koja može biti prouzročena prognoziranim porastom razine mora do kraja 21. stoljeća. Opisane su posljedice koju taj prirodni fenomen može prouzročiti. Analizirana su tri scenarija pojava visoke razine mora: kod stagnacije globalne morske razine te kod porasta za 30 i 60 cm. Analize su napravljene na topografskim kartama mjerila 1:5000. Ustanovljene su najugroženije urbanizirane obalne zone: uvala Sv. Eufemija, luka grada Raba, Supetarska Draga i uvala Lopar. Procijenjen je utjecaj povišenja morske razine na djelovanje valova u istraženim obalnim zonama. Kao posljedica porasta morske razine može se očekivati širenje zaslanjenih priobalnih zona na poljoprivredne površine. Vjerojatno će se pojačati marinske erozije na obalama, što će prouzročiti nazadovanje klifova i/ili smanjenje tijela brojnih pjeskovitih žala. Problem može biti i otežana odvodnja s niskih i zaravnjenih dijelova terena kao i rad lokalne oborinske i fekalne kanalizacije. Mogu biti ugroženi i stambeni objekti koji su posljednjih desetljeća izgrađeni u niskim obalnim zonama, kao i neke građevine u srednjovjekovnoj gradskoj jezgri Raba.The paper describes the vulnerability of the Rab island coastline which may be caused by the forecast sea level rising by the end of the 21st century, including the consequences potentially resulting from this natural phenomenon. Three scenarios of high sea level occurrence were analysed: the case of stagnating global sea levels and the cases of sea level rising by 30 and 60 cm. The analyses were conducted on topographic maps in scale 1:5000. The following urbanised coastal zones were established: Sv. Eufemija cove, Port Rab, Supetarska Draga and Lopar cove. The impact of rising sea levels on the wave action in the investigated coastal zones was estimated. Due to rising sea levels, it can be expected that the salinized coastal zones will spread to agricultural land. It is probable that the marine erosion of the coastline will increase, causing a decline in cliffs and/or decrease in the size of numerous sandy beaches. Further problems may consist in a more difficult drainage of low and flat parts of the terrain and the functioning of the local stormwater and faecal sewerage. Additionally, residential buildings constructed in low-lying coastal zones in the recent decades may be threatened as well, including some structures in the medieval historic centre of the town Rab