RT Journal Article
T1 Phylloceratina ammonoids in the Iberian Basin during the MiddleJurassic: a model of biogeographical and taphonomic dispersalrelated to relative sea-level changes
A1 Fernández López, Sixto Rafael
A1 Meléndez Hevia, Guillermo
AB Phylloceratina and Lytoceratina ammonoids in the Middle Jurassic of the Iberian Chain (E. Spain) represent lessthan 1% of the whole of Ammonoidea. There are two intervals, however, in which their occurrence is remarkablyconstant: within the Upper Bajocian and at the Lower/Middle Callovian boundary. These two dispersal episodes ofPhylloceratina and Lytoceratina into the Iberian Basin are regarded to reflect changes in their palaeoecological andtaphonomical behaviour, as a consequence of regional sea-level changes during the Middle Jurassic. A relative riseduring the Late Bajocian favoured the immigration of juvenile phyllocerataceans. Phylloceras and Adabofolocerasimmigrations gave rise to monospecific assemblages, where they soon died. They did not breed or ontogenicallydevelop in this basin. In contrast, phyllocerataceans recorded at the Lower/Middle Callovian boundary constitutepolyspecific assemblages, dominated by adult individuals. These Callovian assemblages were formed by nekroplanktonicdrift, related to a relative sea-level fall and general homogenization of the shelf bottom, hence favouring theconcentration of remains of organisms from more open marine and oceanic areas.
PB Elsevier B.V.
SN 0031-0182
YR 1996
FD 1996
LK https://hdl.handle.net/20.500.14352/57731
UL https://hdl.handle.net/20.500.14352/57731
LA eng
DS Docta Complutense
RD 8 abr 2025