Kratka vsebina Nadrobne raziskave rude rudnega telesa Grübler so dale vrsto novih podatkov o živosrebrovem rudišču Idrija. Metasomatska ruda v spodnjeskitskem dolomitu je seveda povezana s srednjetriasno magmatsko aktivnostjo. Toda ta ruda je bila kasneje tektonsko pretrta in zdrobljena. Nastale so žilice, žile in rudne breče. Vezivo sestavlja predvsem beli zrnati dolomit, kateremu se v spremenljivih, toda manjših količinah pridružujejo cinabarit, organska snov, kremen in pirit. Te sestavine se pojavljajo v več generacijah, ki so po našem mnenju povezane z delovanjem podtalnice, medtem ko je alpidska orogeneza dvigala rudišče proti površju. Raziskave so dopolnjene z masnospektrometrično analizo izotopske sestave žvepla v cinabaritu ter kisika in ogljika v različnih generacijah dolomita.

Klju~ne besede: Mytilus galloprovincialis, izotopska sestava ogljika, izotopska sestava kisika, Jadransko morje (Hrva{ka)Key words: Mytilus galloprovincialis, isotopic composition of carbon, isotopic composition of oxygen, Adriatic Sea (Croatia) Kratka vsebinaVzorce lupin Mytilus galloprovincialis smo zbrali vzdol' celotne vzhodne Jadranske obale. Analizirali smo izotopsko sestavo ogljika in kisika v kalcitnem in aragonitnem delu skeleta {koljke M. galloprovincialis. S pomo~jo stabilnih izotopov ogljika in kisika smo preverili ali so lupine {koljke M. galloprovincialis dober indikator pogojev v okolju (temperature in slanosti). S pomo~jo izmerjene izotopske sestave kisika v {kolj~nih lupinah in privzete izotopske sestave kisika v vodi smo izra~unali temperature izlo~anja kalcitnega in aragonitnega skeleta {koljke M. galloprovincialis, ki se dobro ujemajo z izmerjenimi temperaturami morske vode. Glede na rezultate izotopske sestave ogljika in kisika v lupinah lahko raziskana obmo~ja razdelimo v tri skupine: z ve~jim vplivom sladke vode, z manj{im vplivom sladke vode in morska okolja, kjer ni vpliva sladke vode. AbstractSamples of Mytilus galloprovincialis were collected from entire Eastern Adriatic coast to determine δ 18 O and δ 13 C performed on calcite and aragonite shell layers. The aim of this work was to check whether shells of M. galloprovincialis are good environmental indicators (water temperature, salinity). Based on measured isotopic composition of oxygen in shell layers and assumed isotopic composition in water temperatures of calcite and aragonite of shell layers were calculated. The calculated temperatures for M. galloprovincialis shell growth of calcite and aragonite shell layer are in good agreement with measured temperatures of sea water. According to our results of δ 18 O and δ 13 C in shell layers we can separate the locations of the investigated area into three groups: those with more influence of fresh water, those with less influence of fresh water and those of marine environments. GEOLOGIJA 49/1, 133-140, Ljubljana 2006 Uvod Lupino {koljke Mytilus galloprovincialis sestavljata aragonit in kalcit. [koljka izlo~a dnevno prirastnice, zato vsebujejo le-te zapis fizikalno-kemijskih pogojev morske vode. [koljka se prehranjuje z me{anico morskega planktona in naseljuje obmo~ja bli'ine sladke vode nizko energijskih okolij, kjer ni ve~jega vpliva valov. Najve~ lupine izlo~i v poletnem ~asu od junija do septembra pri temperaturah morske vode od 22-23 °C, kar

The northern Karavanke Granitic Massif straddles the Slovenian-Austrian border. The investigated area lies in northern Slovenia, and extends from the western Slovenian-Austrian border to the east for about 30 km, with a maximum width of 2 km. The massif exhibits a bimodal magmatic association comprising mainly syenogranite and syenite with contemporaneous gabbroic rocks. Rocks of intermediate composition are less abundant and show field, textural and chemical features suggesting that they have formed as a result of the interaction (mixing and mingling) between felsic and mafic magmas. Plagioclasemantled alkali feldspars occur in dikes of porphyritic syenite, which cut larger bodies of gabbroic rocks. Field, mineralogical, petrographic and geochemical evidences suggest that the porphyritic syenite is a hybrid rock, formed by the interaction of mafic and felsic magmas. The formation of plagioclase-mantled alkali feldspar can be explained by the introduction of alkali feldspar from felsic, syenogranitic magma into more mafic magma, causing local undercooling in the portion of mafic magma surrounding the crystals. This resulted in the growth of cellular plagioclase, with quartz infilling, in a thermally and compositionally equilibrating system.

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