Numerous submarine plateaus form highstanding bathymetric highs at continent to ocean transitions. Due to their proximity to continents, they have been frequently labelled "marginal plateaus", although this term has not been clearly defined or associated with a specific geology or geodynamic process. Until now, these elevations have been interpreted as submerged thinned continental fragments detached from continents, basaltic buildups formed by hotspots, volcanic margins or oceanic plateaus. Many of these plateaus formed at transform margins connecting oceanic basins of contrasted ages. We propose for the first time to define and review a class of marginal plateaus related to a specific tectonic setting: "Transform Marginal Plateaus" (TMPs). Based on a compilation of 20 TMPs around the world, we show that most of them have a polyphased history and have undergone at least one major volcanic phase. Our review highlights in particular a hitherto unrecognized close link between hotspots, volcanic activity and transform margins. We also propose that, due to their polyphased history, TMPs may contain several successive basins and overlooked long-lived sedimentary archives. We finally highlight that, because these TMPs were transform plate boundaries perpendicular or oblique to surrounding rifts, many of them were close to lastcontact points during final continental breakup and may have formed land bridges or bathymetric highs between continents. Therefore, we discuss broader scientific issues, such as the interest of TMPs in recording and studying the onset and variations of oceanic currents or past biodiversity growth, bioconnectivity and lineage evolution.

International audienceThe modern Rhone delta in the Gulf of Lions (NW Mediterranean) is a typical wave-dominated delta that developed after the stabilization of relative sea level following the last deglacial sea-level rise. Similar to most other deltas worldwide, it displays several stacked parasequences and lobes that reflect the complex interaction between accommodation, sediment supply and autogenic processes on the architecture of a wave-dominated delta. The interpretation of a large set of newly acquired very high-resolution seismic and sedimentological data, well constrained by 14 C dates, provides a refined three-dimensional image of the detailed architecture (seismic bounding surfaces, sedimentary facies) of the Rhone subaqueous delta, and allows us to propose a scenario for delta evolution during the last deglaciation and Holocene. The subaqueous delta consists of " parasequence-like " depositional wedges, a few meters to 20–30 m in thickness. These wedges first back-stepped inland toward the NW in response to combined global sea-level rise and overall westward oceanic circulation, at a time when sediment supply could not keep pace with rapid absolute (eustatic) sea-level rise. At the the Younger Dryas-Preboreal transition, more rapid sea-level rise led to the formation of a major flooding surface (equivalent to a wave ravinement surface). After stabilization of global sea level in the mid-Holocene, accommodation became the leading factor controlling delta architecture. An eastward shift of depocenters occurred, probably favoured by higher subsidence rate within the thick Messinian Rhone valley fill. The transition between transgressive (backstepping geometry) and regressive (prograding geometry) (para)sequences resulted in creation of a Maximum Flooding Surface (MFS) that differs from a " classical " MFS described in the literature. It consists of a coarse-grained interval incorporating reworked shoreface material within a silty clay matrix. This distinct lithofacies results from condensation/erosion, which appears as an important process even within supply-dominated deltaic systems, due to avulsion of distributaries. The age of the MFS varies along-strike between ca. 7.8-5.6 kyr cal. BP in relation to the position of depocenters and climatically-controlled sediment supply. The last rapid climate change of the Holocene, the Little Ice Age (1250–1850 AD), had a distinct stratigraphic influence on the architecture and lithofacies of the Rhone subaqueous delta through the progradation of two deltaic lobes. In response to changes in sediment supply linked to 2 rapid climate changes (and to anthropic factors), the Rhone delta evolved from wave-dominated to fluvial dominated, and then wave dominated again

Abstract. Sediment records recovered from the Baltic Sea during Integrated Ocean Drilling Program Expedition 347 provide a unique opportunity to study paleoenvironmental and climate change in central and northern Europe. Such studies contribute to a better understanding of how environmental parameters change in continental shelf seas and enclosed basins. Here we present a multi-proxy-based reconstruction of paleotemperature (both marine and terrestrial), paleosalinity, and paleoecosystem changes from the Little Belt (Site M0059) over the past ∼ 8000 years and evaluate the applicability of inorganic-and organic-based proxies in this particular setting.All salinity proxies (diatoms, aquatic palynomorphs, ostracods, diol index) show that lacustrine conditions occurred in the Little Belt until ∼ 7400 cal yr BP. A connection to the Kattegat at this time can thus be excluded, but a direct connection to the Baltic Proper may have existed. The transition to the brackish-marine conditions of the Littorina Sea stage (more saline and warmer) occurred within ∼ 200 years when the connection to the Kattegat became established after ∼ 7400 cal yr BP. The different salinity proxies used here generally show similar trends in relative changes in salinity, but often do not allow quantitative estimates of salinity.Published by Copernicus Publications on behalf of the European Geosciences Union. U. Kotthoff et al.: Little Belt multi-proxy comparisonThe reconstruction of water temperatures is associated with particularly large uncertainties and variations in absolute values by up to 8 • C for bottom waters and up to 16 • C for surface waters. Concerning the reconstruction of temperature using foraminiferal Mg / Ca ratios, contamination by authigenic coatings in the deeper intervals may have led to an overestimation of temperatures. Differences in results based on the lipid paleothermometers (long chain diol index and TEX L 86 ) can partly be explained by the application of modern-day proxy calibrations to intervals that experienced significant changes in depositional settings: in the case of our study, the change from freshwater to marine conditions. Our study shows that particular caution has to be taken when applying and interpreting proxies in coastal environments and marginal seas, where water mass conditions can experience more rapid and larger changes than in open ocean settings. Approaches using a multitude of independent proxies may thus allow a more robust paleoenvironmental assessment.