%0 Journal Article
%T Migration Routes of the Aptian to Turonian Ostracod Assemblages from North Africa and the Middle East
%A Ashraf M. T. Elewa
%A Omar Mohamed
%J Paleontology Journal
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/459787
%X Quantitative paleobiogeography is a powerful tool for detecting the migration routes of microfossils. This is factual and applicable when we select appropriate analyses for proper problems in the following manner. The quantitative study of 43 selected ostracod species (total of 136 species) from 11 countries of North Africa and the Middle East led to the detection of two migration routes in the late Early to early Late Cretaceous times. The first route of migration was from east to west during the intervals of Aptian-Albian to Cenomanian. While in the Turonian time, reduced oxygen conditions prevailed and minimized the east-west migration. The second route was from north to south for the duration of Aptian-Albian to Cenomanian. On the other hand, four ostracod biofacies, each with its distinctive environmental conditions, have been identified in the studied countries ranging in age from Aptian to Turonian. 1. Introduction Several authors studied the Cretaceous ostracods of the Middle East and North Africa and the paleoenvironmental factors that affected their distribution. However, the pioneer works of Reyment in the sixties of the twentieth century [1¨C3] opened the way to understand the relation between these ostracods and the associated paleoenvironmental conditions. As a result, researchers focused their studies on these regions [4¨C15]. Elewa [14] concluded that there are two main biogeographical provinces that were connected during the Maastrichtian to early Eocene intervals of North and West Africa and the Middle East through the Trans-Saharan Seaway. He, furthermore, proved stability of ostracod habitats in the studied regions [16], and no turnover across the K/Pg boundary can be noticed by ostracods (for details on the mass extinction at the K/Pg boundary, refer to [17¨C22]) as well as the P/E boundary [23]. A close situation has been established by Elewa [24] who studied the ostracod migrations during the middle and late Eocene of Egypt and recorded reduced ostracod migration activity along the shores of Tethys. Conversely, planktonic foraminifers have shown somewhat different situation, where Nishi et al. [25] detected extinction of the foraminiferal marker Morozovella lehneri at lower stratigraphic level in the Eastern Desert of Egypt than in Sinai and the Nile Valley during the middle Eocene, demonstrating the consequence of paleoenvironmental changes on the existence and abundance of Morozovella lehneri. The authors of this paper dealt with investigating the paleobiogeographical and paleoecological inferences of the ostracod assemblages of
%U http://www.hindawi.com/journals/paleontology/2014/459787/