Naslov
Upper Cretaceous rudist architecture in shallow- water environments - examples from Istria (Croatia) and Southern Apennines (Italy).

Autori
Moro, A., Ruberti, D., Tarlao, A., Tunis, G.

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

Izvornik
Tenth International Congress on Rudist Bivalves - Bellaterra, June 22-27, 2014. / Pons, Jose Maria and Vicens, Enric - Barcelona : Universitat Autonoma de barcelona, 2014, 18-18

Skup
Tenth International Congress on Rudist Bivalves.

Mjesto i datum
Barcelona, Španjolska, 22.06.2014. - 27.06.2014

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
Shallow-water paleoenvironments; rudists; Istria; Apeninnes

Sažetak
Upper Cretaceous rudists lithosomes within shallow water environments of southern Istria and Southern Apennines show overview of lateral and vertical evolution of rudists congregations . The lithofacies of investigated profiles are mostly mud-supported limestones with agglutinated and porcelaneous benthic foraminifers. Rudists are characterised by differerent radiolitid genera (mostly Radiolites and Durania) that thrived within subtidal environments through different types of mono- or polispecific congregations, ranging from few tens to few hundreds of individuals . The outcrop exposure allows two and three- dimensional approach for reconstruction of rudist architecture and facies. The leitmotif of the rudist congregations consists of densely-packed individuals in growth position laterally passing to toppled ones. Other rudist bodies are characterised by shell fragments which constitute floatstone. Rudists fragments are the result of bioerosion and less mechanical breakdown. The rudist rich bodies laterally pass to foraminiferal wackestone/packstone. The reconstuced arragment of rudists bodies shows few meter-to-decameter scale lensoidal bodies which corresponds to in situ settlment of individuals. They are characterised by upright growing in situ shells that become generally toppled towards the outer part of the bodies. These meter scale bodies are patchly arranged between floatstone/rudstone, in which the rudists are fragmented beyond any taxonomic recognition. The depositional setting inferred on the basis of facies analysis may be considered of dominantly low energy. The gross lenticular geometry of the rudist bodies and the gradual passage to floatstone/rudstone could be related to pattern of weak currents pathways. The overall occurrence of muddy sediments suggests a low angle, gently dipping depositional environment.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA