34 KB12729 KB31 KB195320252004Caffau, MauroPleničar, Marioštevilka:114 straniletnik:knj. 47str. 41-54ISSN:0016-7789COBISSID:1076821URN:URN:NBN:SI:doc-R25EKFPFenGeološki zavod SlovenijeGeologijaapnenecforaminiferefosilikredaLake KredaNanospaleontologijapaleontologyrudistiSloveniaSlovenijaRudist and foraminifer assemblages in the Santonian-Campanian sequence of Nanos Mountain (Western Slovenia)| Rudistne in foraminiferne združbe v santonijsko-campanijskih plasteh Nanosa (Zahodna Slovenija)|The Santonian-Campanian limestones of Nanos Mountain are mainly characterized by wackestone-packstone with benthic foraminifers, thaumatoporellaceans and rudists. Rudists in growth position are rare and rudist congregations are found only in bouquets with less than ten individuals. Rudist shells are chaotically deposited in beds and frequently show signs of bioturbation and erosion. The analyzed sequence from Nanos Mountain testifies an inner shelf environment in a ramp-like depositional setting. In the lower part of the sequence, rudist assemblages are characterized by abundant hippuritids and radiolitids whereas benthic foraminifers are rare and poorly preserved. In theupper part of the sequence, rudist assemblages consist of abundant radiolitids and rare hippuritids. Benthic foraminifers are usually well-preserved and the presence of the Keramosphaerina tergestina (Stache) is recorded. The vertical distribution of rudist and foraminifer assemblages withthe presence of K. tergestina reflect sea level changes in an inner shelf environment during Santonian-CampanianApnenci santonijske in campanijske starosti so značilni kot tip wackestone-packstone z bentičnimi foraminiferami, thaumatoporelami in rudisti.Rudisti v položaju rasti so redki in rudistne skupnosti najdemo v šopih z manj kot desetimi posameznimi primerki. Lupine rudistov so v plasteh nepravilno razporejene ter pogostno kažejo znake bioturbacije in erozije. Preučevano zaporedje z Nanosa kaže podobno razporeditev kot na pregibu notranjega šelfa . V spodnjem delu zaporedja je rudistna združba značilna po številnih hipuritidih in radiolitidih, medtem ko so bentične foraminifere redke in slabo ohranjene. V zgornjem delu zaporedja so v rudistnih združbah številni radiolitidi in meloštevilni hipuritidi. Bentične foraminifere so navadno dobro ohranjene. Ugotovljena je bila vrsta Keramosphaerina tergestina (Stache). Vertikalna razširjenost rudistnih in foraminifernih združb z vrsto K. tergestina odraža nihanje morske gladine v okolju notranjega šelfa v času santonija in campanijaTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaGeološki zavod Slovenije