Universidad Complutense de Madrid
E-Prints Complutense

Mid-Cenomanian separation of Atlantic and Tethyan domains in Iberia by a land-bridge: The origin of larger foraminifera provinces?

Impacto

Downloads

Downloads per month over past year



Caus Gracia, Esmeralda and Bernaus, J.M. and Calonge, Amelia and Martín Chivelet, Javier (2009) Mid-Cenomanian separation of Atlantic and Tethyan domains in Iberia by a land-bridge: The origin of larger foraminifera provinces? Palaeogeography, palaeoclimatology, palaeoecology , 283 . pp. 172-181. ISSN 0031-0182

[img] PDF
527kB

Official URL: http://www.elsevier.com/wps/product/cws_home/503355/description



Abstract

The Middle and Late Cretaceous shallow-water carbonate platforms widely exposed across the eastern half
of the Iberian Peninsula including the Betic Cordillera, the Iberian Ranges and the Pyrenees provides an
excellent material for analyzing the origin of two Iberian Late Cretaceous larger foraminifera provinces, the
Betic and the Pyrenean: the former corresponds to the Tethyan domain, the latter to the Atlantic domain. The
spatiotemporal distribution in the three studied areas of the larger foraminifera k-strategists, the
Alveolinaceans, from the latest Albian–Cenomanian time interval suggests that separation of the two faunal
provinces started during Early Cenomanian (mid-Cretaceous Global Community Maturation cycle), and the
shelves of the Iberian seaway formed the boundaries of the corresponding bioprovinces. This occurred before
the Betic–Pyrenean communication near the Middle–Late Cenomanian transition was interrupted by a landbridge.
Therefore, the separation of the two bioprovinces cannot be due to the physical barrier created by the
opening or closure of the shallow seaway across the Iberia: here it is attributed to the differences in the
ecological gradients. At the end of the Cenomanian, the Cenomanian–Turonian eutrophication event
eliminated all the k-strategist larger foraminifera to such a degree that all their essential k-strategy
information was lost. The newly arising k-strategist foraminifera needed a considerable time (8–10 m.y.) to
recover their lost genetic complexity: this occurred during the Coniacian in the following GCM cycle.


Item Type:Article
Uncontrolled Keywords:Larger foraminifera, Global Community Maturation cycles, Paleobioprovinces, Middle and Late Cretaceous, Iberia
Subjects:Sciences > Geology > Stratigraphic geology
ID Code:20118
Deposited On:25 Feb 2013 13:06
Last Modified:11 Dec 2018 08:42

Origin of downloads

Repository Staff Only: item control page