Sediment cores collected in eutrophic subalpine Lake Bled (NW Slovenia) were analyzed sedimentologically in terms of grain size, mineralogy and sedimentation rates, and geochemically in terms of metals and nutrients. Surficial sediment is composed of dark gyttya type clayey silt with 5%-10% of organic matter. The sediment below is fine laminated and composed of homogenous silt and clayey silt: Mineralogically, low-Mg calcite prevails, followed by dolomite, quartz, partially of diatomaceous origin, and feldspar. Clay minerals are composed of muscovite/illite and chlorite. Authigenic minerals are pyrite and 'lake chalk' (low-Mg calcite). Lake sediment is especially polluted by Pb, Zn and P. Higher contents were found in the northwestern and eastern parts due to the particle input by local inflows. Increasing eutrophication and pollution, indicated by Cd, Cu, V, Cr, Co and total N and P enrichment in the top layers of the cores, started almost 100 years B.P., and especially 50 years ago.

No abstract

Kratka vsebina Raziskovalno-kapta'na vrtina MET-1/04 pri Bo'akovem, vzhodno od Metlike v Beli Krajini, je globoka 841 m. Namen vrtanja je bil zajeti geotermalno vodo, ki bi bila uporabljena v turisti~ne namene. Obmo~je vrtine le'i na prehodu Zunanjih Dinaridov, ki so v splo{nem zgrajeni iz mezozojskih plitvomorskih karbonatnih kamnin, v Notranje Dinaride. Za slednje so zna~ilne predvsem globljemorske klasti~ne kamnine, ravno tako mezozojske starosti. Strukturna zna~ilnost obmo~ja je niz dinarsko usmerjenih narivov, ob katerih so Notranji Dinaridi narinjeni na Zunanje. Sama vrtina je locirana v zgornjekredni fli{ni skladovnici, ki je odlo'ena transgresijsko na zgornjejurske apnence. Fli{no skladovnico do globine 182,5 m sestavljajo bre~a, konglomerat ter kalkarenit in lapor. Navzdol do globine 275 m sledijo spodnjekredni apnenci, ki pripadajo ali velikim olistolitnim blokom v bazi fli{a ali pa tektonskemu bloku v narivni luski. Do dna vrtine na 841 m nastopajo grebenski apnenci zgornjejurske starosti. Zgornji del apnencev pripada zgornjemu malmu, spodnji del pa je mogo~e 'e spodnjemalmske starosti. V vrtini sta bili ugotovljeni dve vodonosni coni in sicer v intervalu od 92,5 do 184 m ter v intervalu od 220 do 355 m.

Poto~ka zijalka was a station of Aurignatien hunters and the site of rich fossil remains of Pleistocene large mammals. Clastic sediments were deposited in Würm and are an intimate mixture of gravel, sand, silt and clay occurring in various proportions. The fractions form distinct populations, which were transported by different agents, like rockfall, flowing water, ephemeral torrent flows and cryoturbation. The sediment constituents are petrologically rather diverse and indicate that they were derived from different parent rocks -Mesozoic limestone, Permian-Carboniferous shales, Tertiary fine-grained sediments and fluvial pebbly deposits.Bulk chemical composition is strongly influenced by the limestone component, but the majority of trace elements, like Ti, Li, V, Fe, Co, Zn, Ga, Y, REE, Zr, Nb, Cs, Hf and Th originates from clay and fine silt, and Mn, Pb, Ni, Cu and Sn mainly from the heavz minerals in the sand fraction. Ca, Mg, Br, Rb, Sr and U show strong correlation with the amount of carbonate component. Rare earth elements, normalised to PAAS are not appreciable fractionated and show light positive europium anomalies. Kratka vsebinaPoto~ka zijalka je bila postaja aurignacienskih lovcev in je zato tudi bogato nahajali{~e fosilnih ostankov velikih pleistocenskih sesalcev. Klasti~ni sediment je nastal v würmu in predstavlja me{anico gru{~a, proda, peska, melja in gline v najrazli~nej{ih razmerjih. Frakcije vsebujejo populacije, ki so bile transportirane z razli~nimi dejavniki transporta kot so prosti pad, teko~a voda, ob~asni hudourni{ki tokovi in krioturbacija. Sediment sestoji iz drobcev, ki izvirajo iz razli~nih vrst kamnin -mezozojskih apnencev, permokarbonskih skrilavcev, terciarnih drobnozrnatih sedimentov in re~nih prodov.Na celotno kemi~no sestavo mo~no vpliva primes karbonatov. Ve~ina slednih prvin, kot so Ti, Li, V, Fe, Co, Zn, Ga, Y, prvine redkih zemelj, Zr, Nb, Cs, Hf in Th izvira iz gline in melja, Mn, Pb, Ni, Cu in Sn pa iz te'ke frakcije peskov. Ca, Mg, Ba, Rb, Sr in U so vezani na karbonatno sestavino sedimenta. Prvine redkih zemelj, normalizirane na PAAS, ne ka'ejo mo~ne frakcionacije, temve~ le manj{o pozitivno evropijevo anomalijo.

Sediment cores collected in eutrophic subalpine Lake Bled (NW Slovenia) were analyzed sedimentologically in terms of grain size, mineralogy and sedimentation rates, and geochemically in terms of metals and nutrients. Surficial sediment is composed of dark gyttya type clayey silt with 5%-10% of organic matter. The sediment below is fine laminated and composed of homogenous silt and clayey silt: Mineralogically, low-Mg calcite prevails, followed by dolomite, quartz, partially of diatomaceous origin, and feldspar. Clay minerals are composed of muscovite/illite and chlorite. Authigenic minerals are pyrite and 'lake chalk' (low-Mg calcite). Lake sediment is especially polluted by Pb, Zn and P. Higher contents were found in the northwestern and eastern parts due to the particle input by local inflows. Increasing eutrophication and pollution, indicated by Cd, Cu, V, Cr, Co and total N and P enrichment in the top layers of the cores, started almost 100 years B.P., and especially 50 years ago.