Late Neogene Chronostratigraphy, Biostratigraphy, Biochronology and Paleoclimatology
Late Neogene Chronostratigraphy, Biostratigraphy, Biochronology and Paleoclimatology

Author: William A. Berggren

Publisher:

Published: 1973

Total Pages: 834

ISBN-13:

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The integration of modern paleomagnetic, radiometric, and biostratigraphic studies has provided an accurate geochronological framework for the past 10 million years--the Late Neogene. Marine zones based on calcareous and siliceous planktonic organisms are recognized from the sub-Arctic region to the sub-Antarctic and their correlation to the paleomagnetic time scale is now feasible in some detail for the past 5 my. Likewise, the relationship of geochemically calibrated mammalian biochronology to the marine succession has been greatly improved. Within this framework of time it is possible to delineate the history of major features in Late Neogene paleontology, climatology, and oceanography. (Author).

Geological Evolution of the Mediterranean Basin
Geological Evolution of the Mediterranean Basin

Author: Daniel J. Stanley

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 786

ISBN-13: 1461385725

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The Mediterranean Sea, nestled between Africa, southern Europe, and the Middle East, may be envisioned as a complex picture-puzzle comprising numerous intricate pieces, many of which are already in place. A general image, in terms of science, has emerged, although at this time large gaps are noted and some areas of the picture remain fuzzy and indistinct. In recent years this fascinating, mind-teasing puzzle image has become clearer with individual pieces more easily recognized and rapidly emplaced, largely by means of multidisciplinary and multinational team efforts. In this respect, the Special Program Panel on Marine Sciences of the NATO Scientific Af fairs Division considered the merits of initiating four conferences bearing on the Mediterranean ecosystem. It was suggested that the first, emphasizing geology, should dovetail with subsequent seminars on physical oceanogra phy, marine biology, and ecology and man's influence on the natural Medi terranean regime. At a conference held in Banyuls-sur-Mer, France, in August 1979, Profes sor Raimondo Selli was urged by some panel members to initiate an Ad vanced Research Institute (ARI) that would focus primarily on the geologi cally recent evolution of the Mediterranean Sea and serve as a logical base for future NATO conferences on the Mediterranean.

Stratigraphic Record of the Neogene Globorotalid Radiation (planktonic Foraminiferida)
Stratigraphic Record of the Neogene Globorotalid Radiation (planktonic Foraminiferida)

Author: Richard Cifelli

Publisher:

Published: 1986

Total Pages: 224

ISBN-13:

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The histories of lineages forming the Neogene globorotalid radiation in the planktonic foraminifera are reconstructed primarily from stratigraphic distributions. Data on major taxa are synthesized, with particular reference to the development of shell design, and related to biogeograpy and evolutionary strategies.The radiation was established about the base of the lower Miocene by three groups (Fohsella, Globorotalia zealandica lineage, and G. praescitula plexus), which probably arose from separate paragloborotalid lineages.Common trends (size increase, chamber compression, keel development, reduced wall relief) early in the radiation culminated in the evolution of disklike taxa which, since the middle Miocene, have been centered in the tropics. The later phase of the radiation (post middle Miocene) was marked by architectural diversification as spiroconical (e.g., G. margaritae), ventroconical (e.g., G. truncatulinoides), and globose (e.g., G. inflata) taxa arose. Architectural diversification may be linked with watermass differentiation in the late Neogene.Neogene designs have close counterparts in the earlier, but phyletically isolated, Paleogene and Cretaceous radiations. There are also resemblances in ontogenetic strategies and lineage histories. Common adaptations are suggested, but specific functional explanations have not been established.Periods of major redesign are recognized in most lineages and are not confined to speciation events. Examples of stasis in adult morphology occur particularly in taxa that have evolved compressed, keeled shells. Bifurcations in lineages are indistinctly represented by wide spectra of morphotypes. Within the radiation very rapid speciation events are conspicuously absent, although they possibly occurred at the origin of some lineages. The distinctly sluggish tempo of change may be due to large population sizes and their degree of intercommunication. Good examples of allopatric and parapatric speciation were not found, but the prevalence of polytypic taxa, often distributed in contiguous populations showing clinal variation, would favor the inception of parapatric speciation.