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La carta batimorfologica dell’Adriatico Settentrionale che include anche le lagune di Venezia e di Grado e Marano ed è il risultato di una collaborazione tecnico-scientifica tra vari Enti, tra cui il CNR e l’IIM (Istituto Idrografico Militare). La carta è composta da un corpo principale che illustra il modello di elevazione dei fondali marini (risoluzione di 200m) derivato dall’integrazione di tutti i dati acquisiti con ecoscandagli a fascio singolo (single-beam) con una esagerazione verticale di 30x, necessaria ad evidenziare le principali caratteristiche geomorfologiche della piattaforma Nord Adriatica. La carta batimetrica include una serie di poligoni blu (key map) che illustrano la copertura dei dati a maggiore risoluzione raccolti con ecoscandaglio multifascio (Multibeam) acquisiti dal CNR ISMAR, IGAG e dall’IIM, sia lungo costa che in mare aperto, dal 2005 ad oggi. Il rilievo Multibeam della laguna di Venezia, include le tre bocche di porto di Venezia, Chioggia e Malamocco (Madricardo et.al, 2017) è stato integrato al dato Singlebeam, visibile nel corpo carta principale. A destra del corpo carta sono state realizzate sei carte batimetriche ad alta risoluzione che evidenziano i rilievi Multibeam condotti nel porto di Ravenna, alla foce del Fiume Po (Po di Pila) nelle Lagune di Venezia (Laguna Nord e bocca di porto di Chioggia), nel porto di Trieste, nell’area off-shore Ravenna (depositi di sabbie relitte attribuite a depositi trasgressivi). La cartografia è visibile attraverso il WebGIS o scaricabile direttamente al link indicato di seguito.

River deltas are highly dynamical and valuable environments and often undergo strong natural changes and human-induced pressures that need careful observation and monitoring. However, the high dynamicity of submerged deltas makes it very hard to observe how sediment are distributed across the delta area, a crucial element in understanding their morpho-dynamic evolution. To fill this observational gap, in the last few years (2013-2016) repeated high-resolution multibeam bathymetry surveys were carried out for the first time at the Po della Pila delta, the recent-most delta lobe of the Po river. The collected bathymetric and acoustic reflectivity (backscatter), seabed samples and seismic profiler datasets provided insights on the short-term morphological and sedimentological evolution of the extremely dynamic submarine portion of the delta in the framework of the hydrodynamical, seismo-stratigraphical and environmental setting. A high variety of geomorphological features and depositional bodies at different scales were observed from the mouth bar to the prodelta slope such as the alongshore and radial bars under the effect of marine currents, gravitational-instability phenomena and collapse depressions driven by fluid expulsion. Concurrently, the analysis of the seabed reflectivity and sediment samples allowed the identification of two main classes of seafloor sediment, corresponding to dominantly sandy vs. muddy substrata. The comparison among time-lapsed, high-resolution DEMs in the time frame 2013-2016 showed that the main changes occurred on the northern side of the prodelta slope in front of the active channel: mainly as a consequence of the flood of November 2014, a new lobe-shaped fine-sediment deposit up to 4.5 m thick corresponds to a newly-added sediment volume of 1.16 Mm3. Other major morphological changes occurred in the prodelta slope, where radial depositional bars showed a net S-ward migration. Moreover, a generalized seafloor deepening was documented, accompanied by changes in seabed reflectivity with a general coarsening of the delta lobe sediment distribution from the first to the third survey. We document the morphological and sedimentological complexity and the rapidity of the geomorphological changes in the shallow reaches of the Po della Pila lobe. Given the high rates of sediment accumulation and rapid erosion related to storms and currents, this area represents as well a relevant site to study the Anthropocene short-term climate-driven variability of the coastal region including the possible interaction among human-induced changes in sediment supply, coastal erosion, alongshore sediment transport, local subsidence (both natural and anthropogenic) and submarine slope instability.

Although the morphology and morphodynamics of modem tidal inlets have been analysed in a wealth of studies, these systems can be considered representative only for highstand conditions, while little is known about the characteristics and evolution of their transgressive counterparts. Through the analysis of high-resolution seismo-acoustic profiles, this work investigates a rare example of a preserved filled tidal inlet formed during the early Holocene on the continental shelf of the northem Adriatic Sea. The quantity and quality of the available data allowed a detailed reconstruction of the morphology and internal architecture of this feature. This 1.2 km-long, 17 m-thick channelized scour formed in a microtidal environment between 9.0 and 9.5 kyr cal BP. The tidal prism is estimated to have been ca. 4.4 x 10(7) m(3). The internal geometry of the filling material shows no evidence of migration of the inlet, which lasted only for a few centuries and was soon after drowned by the sea transgression. This rapid evolution is in contrast with the millennial-scale lifespan of most of the modern highstand lagoon systems. This work provides a new outlook on the evolution of tidal inlets during phases of marine transgression and in relation to variable rates of sea-level rise. In many cases, paleo tidal inlets are the only witnesses of the presence of transgressive barrier-lagoon systems which had been completely eroded by the wave action after their submersion. These features represent therefore an important proxy to infer the position of the related coastline and to constrain the past relative sea level. (C) 2019 Elsevier B.V. All rights reserved.

Atlantic-type scleractinian cold-water corals occur in the Quaternary of the Mediterranean basin. Most fossil evidence on-land is Early Pleistocene in age, and occurs in peninsular Italy, Sicily and on some Greek islands, whilst submerged situations are by large late Pleistocene. According to circumstances, the mode of preservation of fossil cold-water coral varies sensibly (from loose corals to micritic limestones) what affects the level of confidence of the paleoecological reconstruction. All known situations point about a bathyal setting for such cold-water coral hosting deposits in the Mediterranean basin, but under many respects the geological record of cold-water coral paleoenvironments is yet largely underworked. Research developments are discussed, with special emphasis on the widespread submarine occurrences which prevail over the on-land cold-water coral legacy.

Tidal channels are crucial for the functioning of wetlands, though their morphological properties, which are relevant for seafloor habitats and flow, have been understudied so far. Here, we release a dataset composed of Digital Terrain Models (DTMs) extracted from a total of 2,500 linear kilometres of high-resolution multibeam echosounder (MBES) data collected in 2013 covering the entire network of tidal channels and inlets of the Venice Lagoon, Italy. The dataset comprises also the backscatter (BS) data, which reflect the acoustic properties of the seafloor, and the tidal current fields simulated by means of a high-resolution three-dimensional unstructured hydrodynamic model. The DTMs and the current fields help define how morphological and benthic properties of tidal channels are affected by the action of currents. These data are of potential broad interest not only to geomorphologists, oceanographers and ecologists studying the morphology, hydrodynamics, sediment transport and benthic habitats of tidal environments, but also to coastal engineers and stakeholders for cost-effective monitoring and sustainable management of this peculiar shallow coastal system.

Uranium-series and radiocarbon ages are reported for deep-sea corals Madrepora oculata , Desmophyllum dianthus , Lophelia pertusa and Caryophyllia smithii from the Mediterranean Sea. U-series dating indicates that deep-sea corals have persisted in the Mediterranean for over 480,000 years, especially during cool interstadial periods. The most prolific period of growth however appears to have occurred within the Younger Dryas (YD) period from 12,900 to 11,700 years BP followed by a short (~ 330 years) phase of post-YD coral growth from 11,230 to 10,900 years BP. This indicates that deep-sea corals were prolific in the Mediterranean not only during the return to the more glacial-like conditions of the YD, but also following the rapid deglaciation and transition to warmer conditions that followed the end of the YD. Surprisingly, there is a paucity Last Glacial Maximum (LGM) coral ages, implying they were largely absent during this period when cold-water conditions were more prevalent. Radiocarbon ages show that the intermediate depth waters of the Mediterranean generally had Δ 14 C compositions similar to surface waters, indicating that these waters were extremely well ventilated. The only exception is a narrow period in the YD (12,500 ± 100 years BP) when several samples of Lophelia pertusa from the Ionian Sea had Δ 14 C values falling significantly below the marine curve. Using a refined approach, isolation ages (τ isol ) of 300 years to 500 years are estimated for these intermediate (800–1000 m) depth waters relative to surface marine waters, indicating a reduction or absence of deep-water formation in the Ionian and adjacent Adriatic Seas during the YD. Contrary to previous findings, we find no evidence for widespread intrusion of low Δ 14 C Atlantic waters into the Mediterranean. Prolific growth of deep-sea corals in the Mediterranean ended abruptly at ~ 10,900 years BP, with many of the coral-bearing mounds on the continental slopes being draped in a thin veneer of mud. Their demise is attributed to a number of factors, including the direct loss of habitat due to high sedimentation that accompanied glacial meltwater pulses, together with rising temperatures that would have finally pervaded the deeper water of the Mediterranean following the onset of Holocene warming.

SUMMARY New high-resolution bathymetric and magnetic data from the western Aeolian sector, southern Tyrrhenian Sea, provide insights into structural and volcanic development of the area, suggesting a strong interaction between volcanism and tectonics. The analysis of these data combined with relocated earthquake distribution, focal plane solutions and strain rate evaluation indicates that the dextral strike-slip Sisifo-Alicudi shear zone is a complex and wide area of active deformation, representing the superficial expression of the deep seated lithospheric tear fault separating the subduction slab below Sicily and Calabria. Most of the observed volcanic features are aligned along a NW–SE trend, such as the Filicudi island-Alicudi North Seamount and Eolo-Enarete alignments, and are dissected by hundred-metre-high scarps along conjugate NNE–SSW trending fault systems. The magnetic field pattern matches the main trends of volcanic features. Spectral analysis and Euler deconvolution of magnetic anomalies show the existence of both deep and shallow sources. High-amplitude, high-frequency anomalies due to shallow sources are dominant close to the volcanic edifices of Alicudi and Filicudi, while the main contribution on the surrounding Eolo, Enarete, Alicudi North and Filicudi North seamounts is given by low-amplitude anomalies and/or deeper magnetic sources. This is probably related to different ages of the volcanic rocks, although hydrothermal processes may have played an important role in blanketing magnetic anomalies, in particular at Enarete and Eolo seamounts. Relative chronology of the eruptive centres and the inferred deformation pattern outline the Quaternary evolution of the western Aeolian Arc: Sisifo, Alicudi North and Filicudi North seamounts might have developed in an early stage, following the Late Pliocene–Early Pleistocene SE-ward migration of arc-related volcanism due to the Ionian subduction hinge retreat; Eolo, Enarete and Filicudi represent later manifestations that led volcanoes to develop during Mid-Late Pleistocene, when the stress regime in the area changed, due to the SSE-ward propagation of the subduction slab tear fault and the consequent reorientation and decrease of trench migration velocity. Finally, volcanic activity occurred in a very short time span at Alicudi, where an almost conical volcanic edifice emerged, suggesting negligible interactions with regional fault systems.

Shallow sediment lithology and stratigraphy were investigated at selected areas off Santa Maria di Leuca (SML) on the Apulian margin between 350 and 1200 m water depth, in order to define the sea-bottom character on which coral mounds have developed. According to existing geophysical data and in-situ observations, deep coral growth in the SML area creates patches of colonies typically settled on hard substrates on the upper flanks and/or near the top of mound-like structures and elongated ridges. The sedimentary stratigraphy is strongly influenced by the local topography, which is modeled by tectonic and geomorphological forcing: large-scale erosional features, slope failure and sediment mass accumulation are evident from seismic investigations. Additionally, sites of preferential sediment accumulation due to the action of bottom currents are identified. As a result, a complex sedimentary pattern characterizes this part of the Apulian margin, with strong lateral variability in sediment type and age. Although hemipelagic silty clay constitutes the main lithology, there are sites characterized by periodic accumulation of silt and fine sand and local re-deposition of coarse biogenic sand from the surrounding areas and from shallower depths. Excluding one site, where mid-Pleistocene sediments are brought very close to the bottom-surface due to wide-scale erosion, all collected sediments are late Pleistocene to Holocene in age and fall biostratigraphically within the Emiliania huxleyi acme nannofossil zone. Reworking, detected through nannofossil analysis, is common in most cores, excluding the ones taken from topographic highs, and is variable in extent from site to site and within the sediment column; it includes Cretaceous to Early Pleistocene species, suggesting provenance from extended successions or various stratigraphic levels, outcropping on the submerged Apulian margin or in adjacent land sections. Reworking is often associated with a high content of lithogenic particles and an increase in the coarser (silt) fraction. Coral debris was collected at many stations, both at the sediment surface and within the stratigraphic sequence, with varying abundance in relation to proximity to the coral colonies. Radiometric dating and micropaleontological analyses at some sites allow us to propose a sequence of coral colonization phases.

The paper presents the results of three-dimensional modelling of an area extending over approximately 800 square kilometres along the southern margin of the Po Delta. The geological model describes the Holocene sequence, here approximately 35-40 m thick. Developed on a framework of existing knowledge, it allows a more in-depth analysis of the subsurface stratigraphy of this sector of the Emilia-Romagna plain, identifying five units (including the Pleistocene substrate) that record the transgressive-regressive sedimentary cycle of the last 10 000 years. The geological model is used as base structure for developing 3D thematic mapping by processing cone penetration tests (CPT) data, their derived parameters and data related to the water quality of the coastal aquifer. Integration and correlation of the onshore geological data with marine geophysics and seabed core drillings has enabled the creation of a detailed model of recent deltaic and littoral morpho-depositional elements. This study shows that 3D modelling yields suitable tools for the insight and representation of the subsurface architecture and affords a better understanding of processes such as subsidence, saltwater intrusion into aquifers and the dynamics of coastal sands, processes, which are currently a matter of concern for the Emilia-Romagna regional government.

Subfossil azoxanthellate deep-sea coral mounds occur at 355–410 m on the continental slope of the NE Tyrrhenian Sea between Gorgona and Capraia islands, Tuscan Archipelago. These low-relief patch reefs are at present buried by a thin muddy drape. Their age is latest Pleistocene. The colonial scleractinian Madrepora oculata is the major frame builder, in association with the solitary coral Desmophyllum dianthus and the colonial coral Lophelia pertusa. These NE Tyrrhenian Madrepora-dominated coral mounds represent one of the few known Mediterranean examples of deep-coral colonization of a muddy, low-gradient continental slope.

Various types of submarine diagenetic products occur at bathyal depths (>300 m) along the Gorgona slope, eastern Tyrrhenian Sea. Bottom sampling during cruise LM-99 of the R/V Urania recovered pristine to diagenetic altered shells (including steinkern) and phosphatized/carbonate hardgrounds. Chemical maps (Al, Ca, Si, S, Fe, P) are provided to characterize these diagenetic products. A peculiar category of steinkern (black molds) of benthic invertebrate calcareous shells is the result of pervasive substitution by phosphomicrite and glaucony. Chemical precipitation and mineral replacement at the expense of pelagic sediment and skeletal carbonates took place under prolonged conditions of exposure at the seawater–sediment interface.

The Istituto di Scienze Marine (ISMAR-CNR) has conducted several research projects on the Italian side of the Adriatic Sea over more than 15 years, collecting bathymetric, geophysical and sediment core data to perform multidisciplinary studies of modern sediment dynamics and of past environmental changes during the last eustatic cycle. A crucial step in this direction was the construction of a detailed bathymetry, a time-consuming task due to the extensive shallow water portion of the basin. Given the setting of the Adriatic Sea and the long-lasting research effort, the bathymetric map is necessarily based on heterogeneous data with uneven spatial distribution of Single-Beam echo-soundings. The main objective of this work is to illustrate the methodology applied to compile the bathymetric map of the west side of the Adriatic Sea at basin scale (1:750,000) and to describe the main morphological units that characterise the seafloor and reflect its main geological features. This bathymetry can also be used in oceanographic modelling both at regional and local scale, focussing on the interaction between bottom currents and seafloor morphology.

Il fenomeno dell'erosione costiera interessa circa 35 km della costa emiliano-romagnola e comporta gravi rischi per le infrastrutture, l'ambiente e l'economia turistica. Per contrastare tale tendenza la Regione Emilia-Romagna ha effettuato molteplici studi e sperimentazioni e, nell'ambito del programma di Gestione Integrata della zona costiera, ha deliberato di adottare il ripascimento quale tecnica prioritaria di intervento (Linee guida GIZC 2005). In questa ottica vengono condotti interventi cosiddetti 'ordinari', che sono quelli stagionali o volti a sanare le situazioni più critiche derivate da eventi di mareggiata particolarmente energetici, e interventi 'straordinari' che vengono effettuati ogni 5-6 anni al fine di compensare il sistema delle perdite di sedimento legate alla subsidenza e al mancato apporto di sabbia da parte dei fiumi. Per i primi si utilizzano sedimenti provenienti da accumuli litoranei, o in subordine da cava, mentre per gli interventi straordinari si sono utilizzate le sabbie dei depositi sottomarini, rinvenuti ad una distanza di circa 30-40 miglia al largo della costa regionale alla profondità del fondale di circa 30-50 metri. Tali depositi sono stati individuati nel corso degli anni '80 e '90 grazie ai numerosi rilievi (Colantoni et al., 1979; 1990; IDROSER SpA, 1985; 1990) condotti da ARPA Ingegneria Ambientale (ex Idroser) e ISMAR-CNR di Bologna (ex IGM-CNR). Recentemente è stata fatta una stima delle risorse di sabbia presenti al largo della costa della regione Emilia-Romagna, quantificata in 78 milioni di m3 (Correggiari et al., 2011). Negli ultimi 10 anni la Regione ha portato a termine due interventi "straordinari" nel 2002 e nel 2007, alimentando rispettivamente 8 e 7 spiagge, monitorate sia nel corso degli interventi che negli anni successivi (Preti M., 2011; Aguzzi et al., 2011). La quantità di sabbia apportata al sistema è stata, in totale, di circa 1,6 milioni di m3. I depositi di sabbia sottomarini sono una risorsa non rinnovabile che deve quindi essere gestita in modo oculato, con una logica di sostenibilità ambientale ed economica. A tal fine, per un miglior controllo delle strategie di sfruttamento, si rendono necessari piani e strumenti di controllo, quali un sistema informativo che raccolga tutti i dati acquisiti e le loro elaborazioni. In tale contesto il Servizio Geologico, Sismico e dei Suoli ha stipulato nel 2009 una convenzione con ISMAR-CNR di Bologna per la realizzazione di uno strumento informatico utile alla verifica delle operazioni di dragaggio e alla costruzione di scenari di intervento per la preparazione dei progetti esecutivi. Il prodotto potrà essere inserito all'interno del Sistema Informativo del Mare e della Costa. Altri geodatabase già realizzati, o in corso di sviluppo che risultano strettamente collegati al in_SAND, sono il Database dei Ripascimenti e il Database dell'Uso del Mare.

Recent investigations of the Eastern Mediterranean Sea carried out during the GECO cruise with RV Urania provided a substantial number of new cold-water coral (CWC) records, including branching and solitary scleractinian species. These new sites are located along steep escarpments and on topographic highs along the margins of Crete, Karpathos, and Rhodes. The majority of the corals represent fossil occurrences, predominantly Late Pleistocene assemblages. Our research documents that the Eastern Mediterranean Basin has been colonized by CWC at favorable times during the Last Glacial, in particular during the Younger Dryas. Schizocyathus fissilis is reported for the first time for the Mediterranean, while the finding of Ceratotrochus magnaghii represents the first record for the Eastern Mediterranean. Various coral facies occur on the southerly island slopes of Crete, Karpathos, and Rhodes, including hardgrounds and loose skeletal sediments. Hardgrounds occur on steep topographies between ca. 500 and 1,700 m, and can conveniently be subdivided as (1) Neopycnodonte-Desmophyllum framestone, (2) Desmophyllum-Caryophyllia framestone, (3) Madrepora-Lophelia rudstone, (4) Pelagic mudstone and wackestone, and (5) Siliciclastic-carbonate conglomerate and breccia. Unconsolidated skeletal sediments containing corals mainly occur on gentler topographic situations between ca. 140 and 600 m and can be subdivided as: (A) Lophelia-Madrepora rubble, (B) Dendrophyllia rubble, (C) Stenocyathus rubble, (D) Caryophyllia calveri rubble, and (E) fine-grained sediment with octocoral axes. Many of these facies types are also present in the western part of the Mediterranean and have fossil representatives from the Pleistocene to the Recent. Radiocarbon dating (AMS-C-14) reveals Younger Dryas ages between 12.4 and 12.0 ka cal BP for Lophelia pertusa and Madrepora oculata. Desmophyllum dianthus occurs during the Last Glacial Maximum (21.8 ka cal BP) and the Younger Dryas (11.7 ka cal BP), as well as during the Late Holocene and subrecent times (4.4-0.6 ka cal BP). Caryophyllia sarsiae occurs during the Late Glacial (15.5 ka cal BP), while Caryophyllia calveri occurs during the Early Preboreal (10.8 ka cal BP). The ages for the framework-constructing corals L. pertusa and M. oculata are coherent with their temporal predominance during the Younger Dryas in other parts of the Mediterranean.

The Bari Canyon System (BCS) is a peculiar erosional–depositional feature characterised by two main, almost parallel, conduits emanating from a broad crescent-shaped upper slope region. When viewed in cross sections parallel to the margin, BCS appears markedly asymmetric with a right hand (southern) side that is higher and steeper (about 800 m in relief and more than 30° steep). The left-hand side of the canyon is instead much smoother. As a consequence, bottom currents flowing along the slope from the north enter the canyon and interact with its complex topography leading to preferential deposition on the up-current side of pre-existing morphological relief. Where mass-failure deposits generate morphologic relief, outside the canyon, sediment is preferentially deposited up current (N-ward). BCS includes three main EW-oriented sediment conduits: Canyon C, to the south, Channel B, in the central area, and Moat A in the north. Channel B shows a well developed levee deposit on its right-hand side and appears markedly straight and erosional on the upper slope. The deepest portion of Channel B is substantially abandoned and draped but still shows a subdued thickening of the draped unit north (and up current) of pre-existing morphologic relief, confirming the impact of along-slope flowing currents. Canyon C is flanked by erosional walls all the way to the basin floor where deep-sea furrows develop with a NW–SE orientation. Today, dense water formation in the Adriatic is seasonally modulated and displays a significant variability on inter-decadal scales. Dense water formation during glacial intervals was likely different from the modern because most of the North Adriatic shelf was subaerially exposed and the deep water mixing in the south was likely reduced, as suggested by paleoceanographic reconstructions. The growth patterns of BCS since the LGM are characterised by concurrent erosion of the upper portion of Channel B and of the lower portion of Canyon C. It is possible that flows through the straight, narrow and steep upper segment of channel B spill over its right hand levee in ca. 600 m water depth, where the relief of levee B on the channel floor is minimal, and enter Canyon C, where substantial erosion takes place. In this view, the upper portion of Canyon C, where hard grounds and corals are encountered, is flushed by currents characterised by reduced turbidity, while the lower part of Canyon C collects additional flows from upper channel B.

Late Miocene Lago-Mare macrofossiliferous sediments were recovered in the northeastern Tyrrhenian Sea by dredging the continental slope off Gorgona Island, Tuscan Archipelago, at 300–470 m depth. The fossil assemblage consists of a rich lymnocardiid bivalve fauna dominated by Pontalmyra ex gr. P. incerta (Deshayes), associated with Dreissena ex gr. D. rostriformis (Deshayes), Pontalmyra cf. partschi (Mayer), “Limnocardium” sp., the gastropods Melanopsis narzolina (D’Archiac), Melanopsis sp. and cf. Saccoia sp. All bivalve taxa recognized at species level are of Paratethyan (Pontian) affinity and widespread in the Late Miocene of the Mediterranean Basin while M. narzolina has so far only recorded from the Mediterranean Basin. This finding represents the most diverse Lago-Mare macrofauna reported thus far from any submerged location in the Mediterranean Basin and documents that the post-evaporitic Cusercoli Formation contributes to the syn-rift neoautochthonous units of this sector of the Northern Tyrrhenian Sea.

Zooxanthellate scleractinian corals have been shown to preserve important archives of seasonal variations of climate variables, such as sea surface temperature, salinity, and productivity. By analogy, the recognition of correlated chemical signals in azooxanthellate deep-water corals may provide an important new approach to help unravel the role of intermediate and deep waters in determining climate variability. A first step to determine the suitability of deep-water scleractinian corals as potential paleoceanographic-paleoclimatic tools requires the demonstration of coherent geochemical signals in their skeletons. With this in mind, trace and minor element ratios Sr/Ca, Mg/Ca, U/Ca, B/Ca, P/Ca, Ba/Ca and Mn/Ca have been measured in two deep-water solitary scleractinian corals (Desmophyllum dianthus) collected from Last Glacial submerged banks in the Mediterranean basin and in the Great Australian Bight. Most elements show distinct, highly correlated patterns of variation. Although preliminary, these results illustrate the potential use of trace and minor element concentrations in the deep-water scleractinian corals to provide new constraints on the composition and evolution of intermediate and deep waters and thus introduce new perspectives in paleoceanography, such as the assessment of changes in both deep-sea nutrient chemistry and ocean circulation.