The Eocene–Oligocene transition in the C-isotope record of the carbonate successions in the Central Mediterranean

The Eocene-Oligocene transition marks a fundamental step in the evolution of the modern climate. This climate change and the consequent major oceanic reorganisation affected the global carbon cycle, whose dynamics across this crucial interval are far from being clearly understood. In this work, the upper Eocene to lower Oligocene δ13CCarb and δ13CTOC records of a shallow-water and a hemipelagic carbonate settings within the Central Mediterranean area have been studied and discussed. The shallow-water carbon isotope signal has been analysed in the northern portion of the Apula Platform, cropping out in the Majella Mountain, Central Apennines (Santo Spirito Formation). A coeval Umbria-Marche basinal succession has been investigated in the Massignano section (Conero area, Central Italy). The purposes of this work are: to discriminate between the global and the local (Mediterranean) signature of C-isotope record during the Oi-1 event, to correlate the regional C-isotope signal with the global record, and to evaluate the carbon cycle dynamics across the greenhouse-icehouse transition through the integration of complementary records (shallow-water vs pelagic settings, δ13CCarb vs δ13CTOC). The upper Eocene carbon isotope record of the analysed successions matches with the global signal. The overall trend shows a decrease of the δ13CCarb and a contemporary increase of the δ13CTOC. The decoupling of the two curves is consistent with a reduced fractionation effect by primary producers that characterised the interval between the Middle Eocene Climatic Optimum and the onset of the Oi-1 event. However, regional factors superimposed the global signal. In fact, the upper Eocene basinal δ13CTOC record is marked by short-term negative spikes, which possibly represent times of higher productivity triggered by the westward subtropical Eocene Neotethys current entering from the Arabian-Eurasian gateway. On the contrary, the shallow-water record does not display these short-term productivity pulses. A change in the carbonate factory is only recorded at the Eocene-Oligocene transition, marked by a reduction of the larger benthic foraminifera and the spread of seagrass and corals. Moreover, in the shallow-water record of the Santo Spirito Formation, no major carbon isotope shift related to the Oi-1 event is recorded due to the presence of extensive slumps that disrupt the bedding. These slumps are the main evidence of the sea-level drop that occurred concomitantly with the onset of the Antarctica ice-sheet, which caused the deepening of the storm wave base and increased the instability over the entire ramp

Does the Bari Canyon (Central Mediterranean) influence the fish distribution and abundance

Abstract The objective of this study was to evaluate whether the Bari Canyon influences the distribution and abundance of fish fauna in the southern Adriatic Sea. Data were collected in the Bari Canyon and in an adjacent area on the continental slope during an experimental longline survey carried out in June 2015. A total of 19 fish species were collected (16 inside and 13 outside the canyon). Differences between the sites were evaluated by means of a set of univariate and multivariate methods (analysis of variance, permutational multivariate analysis of variance, non-metric multidimensional scaling). The abundance and biomass of the whole catch were significantly greater inside than outside the canyon. The most abundant species were the shark Galeus melastomus and the teleost fishes Conger conger, Helicolenus dactylopterus, Merluccius merluccius, Pagellus bogaraveo and Phycis blennoides. All these species were found to be more abundant in the canyon than in the adjacent area. However, a significantly greater abundance inside the canyon than outside was detected for C. conger, while P. blennoides showed both significantly greater abundance and biomass in the canyon than outside. P. bogaraveo was exclusively caught inside the canyon. C. conger and P. blennoides exhibited significant differences in their sizes between the canyon and the adjacent area: a greater number of both smaller and larger individuals were found in the canyon than on the open slope. Mature females and males were mostly observed in the canyon in all the most abundant species, with the exception of P. blennoides due to its autumn-winter spawning. The present study corroborates the role of the Bari Canyon as a refuge area and an Essential Fish Habitat for fish species exploited in the neighbouring fishing grounds, highlighting the need for conservation measures

The VISTA datasets, a combination of inertial sensors and depth cameras data for activity recognition

This paper makes the VISTA database, composed of inertial and visual data, publicly available for gesture and activity recognition. The inertial data were acquired with the SensHand, which can capture the movement of wrist, thumb, index and middle fingers, while the RGB-D visual data were acquired simultaneously from two different points of view, front and side. The VISTA database was acquired in two experimental phases: in the former, the participants have been asked to perform 10 different actions; in the latter, they had to execute five scenes of daily living, which corresponded to a combination of the actions of the selected actions. In both phase, Pepper interacted with participants. The two camera point of views mimic the different point of view of pepper. Overall, the dataset includes 7682 action instances for the training phase and 3361 action instances for the testing phase. It can be seen as a framework for future studies on artificial intelligence techniques for activity recognition, including inertial-only data, visual-only data, or a sensor fusion approach

Daily gesture recognition during human-robot interaction combining vision and wearable systems

The recognition of human gestures is crucial for improving the quality of human-robot cooperation. This article presents a system composed of a Pepper robot that mounts an RGB-D camera and an inertial device called SensHand. The system acquired data from twenty people who performed five daily living activities (i.e. Having Lunch, Personal Hygiene, Working, House Cleaning, Relax). The activities were composed of at least two "basic" gestures for a total of 10 gestures. The data acquisition was performed by two cameras positioned laterally and frontally to mimic the real conditions. The acquired data were off-line classified considering different combinations of sensors to evaluate how the sensor fusion approach improves the recognition abilities. Specifically, the article presents an experimental study that evaluated four algorithms often used in computer vision, i.e. three classical machine learning and one belonging to the field of deep learning, namely Support Vector Machine, Random Forest, K-Nearest Neighbor and Long Short-Term Memory Recurrent Neural Network. The comparative analysis of the results shows a significant improvement of the accuracy when fusing camera and sensors data, i.e. 0.81 for the whole system configuration when the robot is in a frontal position with respect to the user (0.79 if we consider only the index finger sensors) and equal to 0.75 when the robot is in a lateral position. Interestingly, the system performs well in recognising the transitions between gestures when these are presented one after the other, a common event in the real-life that was often neglected in the previous studies

Global versus regional influence on the carbonate factories of Oligo-Miocene carbonate platforms in the Mediterranean area

The Oligocene-Miocene is a key interval that was characterized by a cooling trend associated with a progressive decrease of atmospheric CO2 concentrations that ends in the Present days. In the Central Mediterranean area, during this interval, three main carbonate platform domains developed in the foreland zone of the Apennines: the Latium-Abruzzi-Campana and Apulia domain in the central and south-eastern sectors of the chain and the Hyblea and Pelagian carbonate platforms in the south and south-western sectors. This work analyzes the impact and interplay of global and regional factors controlling the development of different carbonate factories and facies associations over the Chattian and the early Messinian time interval. Three well-studied examples of the central Mediterranean will be used: the Chattian ramp of Malta, the Latium-Abruzzi ramp, and the Bolognano ramp within the northern portion of the Apulian carbonate platform (outcropping on Majella Mountain). The Malta ramp represents the reference model for the heterozoan Oligo-Miocene carbonate factory, since it developed far from terrigenous input, in persistent oligotrophic conditions, and within a tropical climate. In contrast, the evolution of the central Apennine ramps is strictly related to the geodynamic evolution of the Apennines and simultaneously to global oceanographic changes. The Chattian Apennine ramps are affected by a basin conformation that favored the development of dominant currents and related dune fields. Successively, these ramps were exposed to strong Aquitanian volcanism that induced a shift towards an aphotic-dominated carbonate factory. Since the Burdigalian the development of the Apennines has affected the evolution of the investigated ramps through the eastward migration of foredeep systems and related nutrient input. This influence becomes more evident between the Tortonian and Messinian, during which reef-rimmed platforms developed in the rest of the Mediterranean while red algae still dominated in the Apennine ramps. Amongst the global events, the Ccycle perturbation, occurring between the late Burdigalian and Serravallian (Monterey event), leaves a clear sign on the two Apennine ramps

The lower Rupelian cluster reefs of Majella platform, the shallow water record of Eocene to Oligocene transition

The Eocene-Oligocene Transition is a key interval in the evolution of the modern climate, representing the last greenhouse-icehouse transition faced by the Earth. Shallow-water carbonate systems hold essential information of the global changes related to the E-O Transition. In this work, we focus on the Majella Mountain carbonate ramp to identify the shallow-water sedimentary expression of the oceanographic and sea-level changes related to the E-O Transition, and to compare it with the deep-marine records and the coeval shallow-water successions. Field observations, coupled with the study of thin sections to identify textural characters, and of the larger benthic foraminiferal associations for biostratigraphic purposes, allowed reconstructing the depositional model and the stratigraphic distribution of the examined ramp. The lower Rupelian ramp outcropping in the Majella Mountain is characterized by seagrass meadows in the euphotic inner ramp. Corals developed in the middle ramp, building mounded cluster reefs in the mesophotic zone, below wave base, in high hydrodynamic conditions produced by rip-currents induced by storm events or by the breaker zone of internal-waves. The outer ramp consists of alternating bioturbated wackestone rich in planktonic foraminifera, bioclastic packstone and skeletal rudstone to floatstone. The depositional model of the Oligocene ramps is the result of the major changes that occurred during the greenhouse-icehouse transition. In the Majella platform, the E-O Transition corresponds to an unconformity developed on the Priabonian substrate, where the cluster reefs grew and expanded. The unconformity results from the sea level drop of tens of meters, recorded also in the outer ramp, related to the Oi-1 event. The cluster reefs started to develop when the Priabonian ramp was flooded and continued to grow during the following highstands, forming an extensive coral unit that prograded basinwards, interfingering with the outer ramp deposits