Naslov
Characteristic fossils of Spiroplectinella carinata Zone from Dubravica, Medvednica Mt., Croatia

Autori
Mikša, Goran ; Miletić, Danica

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
22nd IAS Meeting of Sedimentology, Abstracts Book / Vlahović, Igor - Zagreb : Institut za geološka istraživanja, Zagreb, 2003, 130-130

Skup
22nd IAS Meeting of Sedimentology

Mjesto i datum
Opatija, Hrvatska, 17.09.2003. - 19.09.2003

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
Medvednica Mt.; Spiroplectinella carinata Zone; micropaleontology

Sažetak
In the area of Dubravica, on the south slopes of Mt. Medvednica a large outcrop was opened by progressing of local construction works a few years ago. The exposed beds contain a numerous fossils, giving a well sample of Spiroplectinella carinata Zone of Upper Badenian (Šikić, 1967). The micropaleontological analyses have been examined on washed samples. Succession begins with breccias which represent a transgressive member on Upper Triassic dolomite. The same contact is more clearly visible thirty meters to the northwest. Breccias are predominantly composed of dolo-mitic particles from the basement. After breccias, follows half a meter of porous coralinacean biocalcarenites with rare oyster fragments, locally known as litavac (Pikija et al., 1995). More fossiliferous beds overlie biocalcarenites, and are represented as about one meter of oyster limestones. Oysters and other mollusca are mixed with their fragments and show occasionally strong reworking and abrasion of shell surface. Foraminiferal fauna is badly preserved and is characterized by shallow water Ammonia beccarii (Linn&egrave ; ), Elphidium crispum (Linn&egrave ; ) and Operculina sp. The succession continues with three meters of dark blue-grayish marly limestones with abundant mollusc fauna Chlamys elegans Andrzejowsky, Panopaea sp. and Ficula geometra Borson. Large species of echinoids Heteroclypeus cotteaui Lambert are also present. Benthic foraminiferal fauna is represent by Cibicides lobatulus (Walker & Jacob), Elphidium fichtelianum (d&#8217 ; Orbigny), Florilus boueanus (d&#8217 ; Orbigny), Cancris auriculus (Fichtel & Moll) and few specimens of Spiroplectinella carinata (d&#8217 ; Orbigny), Cibicidoides ungerianus (d&#8217 ; Orbigny), Textu-laria sp., Operculina sp. Planktonic forams are rare (Globi-gerinoides trilobus (Reuss)). Top of the outcrop consists of sandy clay with a numerous and well preserved fossils of Isocardia cor Linnč, Corbula gibba Olivi, Venus multilamella (Lamarck), Tellina div.sp., Lucina sp., Turritella subangulata (Brocchi), Turritella erronea Cossmann, Natica sp., Schizaster sp. and corals. Foraminiferal fauna is characterized by abundant deeper water benthic species Spiroplectinella carinata (d&#8217 ; Orbigny), Textularia ex. gr. gramen (d&#8217 ; Orbigny), Cibicidoides ungerianus (d&#8217 ; Orbi- gny), Florilus boueanus (d&#8217 ; Orbigny). Less frequent are Hoeglundina elegans (d&#8217 ; Orbigny), Globulina tuberculata d&#8217 ; Orbigny, Guttulina communis (d&#8217 ; Orbigny), Cassidulina crassa d&#8217 ; Orbigny, Lenticulina rotulata (Lamarck), Heterolepa div.sp., Ceratobulimina sp., Asterigerina sp., Praeglobulimina sp., Valvulineria sp., Bulimina sp., Melonis sp., Pullenia sp., uvigerinids, some nodosarids and miliolids. The connection with the open sea is documented by planktonic foraminifera Globigerinoides trilobus (Reuss) and Globigerina div.sp. The results of paleontological studies have shown that marine conditions changed from inner to middle shelf environment during the Badenian (Papp & Schmid, 1985). Communication with open sea existed to the end of Bade-nian.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA