Miocene paleoceanographic evolution of the Mediterranean area and carbonate production changes: A review

Abstract Miocene is a key interval in the global climate evolution as well as in the geodynamic evolution of the Mediterranean basin. Therefore, global and regional factors controlled Miocene Mediterranean oceanography, which, in turn, affected carbonate production. In this work, we review the Miocene paleocenographic evolution of the Mediterranean starting from its Sr and Nd isotope records. Secondly, we discuss Mediterranean shallow-water carbonate production changes to identify the role of oceanographic conditions in controlling carbonate systems' evolution. During Aquitanian, Sr and Nd isotope records attest an open Mediterranean, mainly fed by the Indian Ocean. From the late Burdigalian, the intermittent connection with the Indian Ocean changed the overall circulation in the basin, leading to higher residence time of waters and smaller water exchanges with the adjacent oceans. In this newly established paleoceanographic framework, regional factors such as volcanism, significantly affected Mediterranean seawater chemistry. Local tectonics led to the development of small sub-basins in the Eastern Mediterranean, characterized by restricted water exchanges from the Tortonian in the easternmost part, to the early Messinian, as attested by the deviation of the Sr isotope record of the proto-Adriatic basin. Larger Benthic Foraminifera (LBF) assemblages dominated carbonate production in the Aquitanian, while they were the most affected by the Indo-Pacific closure, showing a demise after the Burdigalian. With the LBF demise, red algae and bryozoans dominated carbonate ramps from the middle Miocene to the Tortonian. Bryozoans in particular spread during the Monterey Event, favoured by global and regional factors. During early to middle Miocene, corals formed mounds in the oligophotic zone or coral carpets controlled by local conditions. Conversely, in the late Tortonian-early Messinian, they developed as huge reef complexes in the Western and Central Mediterranean, with the exception of small restricted sub-basins, such as the proto-Adriatic basin, where red algae and small benthic foraminifera persisted

Overview of the RFX Fusion Science Program

With a program well-balanced among the goal of exploring the fusion potential of the reversed field pinch (RFP) and that of contributing to the solution of key science and technology prob- lems in the roadmap to ITER, the European RFX-mod device has produced a set of high-quality results since the last 2010 Fusion Energy Conference. RFX-mod is a 2 MA RFP, which can also be operated as a tokamak and where advanced confinement states have 3D features studied with stellarator tools. Self-organized equilibria with a single helical axis and improved confinement (SHAx) have been deeply investigated and a more profound understanding of their physics has been achieved. First wall conditioning with Lithium provides a tool to operate RFX at higher density than before, and application of helical magnetic boundary conditions favour stationary SHAx states. The correlation between the quality of helical states and the reduction of magnetic field errors acting as seed of magnetic chaos has been robustly proven. Helical states provide a unique test-bed for numerical codes conceived to deal with 3D effects in all magnetic configura- tions. In particular the stellarator equilibrium codes VMEC and V3FIT have been successfully adapted to reconstruct RFX-mod equilibria with diagnostic input. The border of knowledge has been significantly expanded also in the area of feedback control of MHD stability. Non-linear dynamics of tearing modes and their control has been modelled, allowing for optimization of feedback models. An integrated dynamic model of the RWM control system has been developed integrating the plasma response to multiple RWMs with active and passive conducting structures (CarMa model) and with a complete representation of the control system. RFX has been oper- ated as a tokamak with safety factor kept below 2, with complete active stabilization of the p2, 1q Resistive Wall Mode (RWM). This opens the exploration of a broad and interesting operational range otherwise excluded to standard tokamaks. Control experiments and modelling led to the design of a significant upgrade of the RFX-mod feedback control system to dramatically enhance computing power and reduce system latency. The possibility of producing D-shaped plasmas is being explore