Objectif
Marine magnetic anomalies constitute the backbone of plate tectonic studies. Together with the known time scale of past polarity reversals of the geomagnetic field, these anomalies can be used to date the oceanic crust. However, periods of several tens of million years (Myr), when the polarity of the geomagnetic field remained stable (i.e. superchrons), lack prominent magnetic anomalies and therefore prohibit the construction of plate kinematic models. Thus far, internal anomalies formed by past fluctuations in the strength of the geomagnetic field have never been used to create plate reconstruction models. To understand how tectonic motions evolved during the Cretaceous normal superchron (CNS, between ~121 and 83 Myr ago) and their coupling nature with mantle convection processes, there is a growing need for cross-disciplinary and innovative quantitative studies. I plan to investigate the behavior of the geomagnetic field during the CNS and to use its past fluctuations to construct the first plate kinematic models for the Cretaceous superchron. I will use marine magnetic records to create age models and to calculate past plate motions for the South and Central Atlantic, the southeast Indian, and the North Pacific Oceans. This, in turn, will improve our understanding of both the oceanic and continental realms. The new insights from the proposed project will enable better modeling of continental marginal basins, the breakup of Gondwana. The results of the proposed research will provide the first direct constraints on plate motions during this long interval and will advance our understanding of the interplay between surface tectonic plates, mantle convection, and geomagnetic field processes. Finally, the new kinematic models will be used to investigate crustal production rates and spreading rates that controlled the abnormally high sea levels that prevailed during the mid-Cretaceous.
Champ scientifique
Appel à propositions
FP7-PEOPLE-2012-CIG
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Régime de financement
MC-CIG - Support for training and career development of researcher (CIG)Coordinateur
84105 Beer Sheva
Israël