Direct traces of past sea levels are based on the elevation of old coral reefs at times of sea-level highstands. However, these measurements are discontinuous and cannot be easily correlated with climate records from ice cores. In this study we show a new approach to recognizing the imprint of sea level changes in continuous sediment records taken from the continental slope at locations that were continuously submerged, even during periods of sea-level lowstand. By using a sediment core precisely synchronized with Greenland ice cores, we were able to recognize major floods of the Mediterranean continental shelf over the past 270 kyr. During the last glacial period five flooding events were observed at the onset of the warmest Greenland interstadials.Consistent correspondence between warm climate episodes and eustatic sea level rises shows that these global flooding events were generated by pronounced melting of the 2 Northern Hemisphere ice-sheets, due to rapid intensification of Atlantic Meridional Overturning Circulation.The method described in this study opens a new perspective for inter hemispheric synchronization of marine climate records if applied in other continental margins from the Southern Hemisphere or the equatorial regions.

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Integrated Ocean Drilling Program Expedition 313 continuously cored uppermostEocene to Miocene sequences on the New Jersey shallow shelf (Sites M27, M28, and M29). Previously, 15 Miocene (ca. 23-13 Ma) seismic sequence boundaries were recognized on several generations of multichannel seismic profi les using criteria of onlap, downlap, erosional truncation, and toplap. We independently recognize sequence boundaries in the cores and logs based on an integrated study of core surfaces, lithostratigraphy and process sedimentology (grain size, mineralogy, facies, and paleoenvironments), facies successions, stacking patterns, benthic foraminiferal water depths, downhole logs, core gamma logs, and chronostratigraphic ages. We use a velocitydepth function to predict the depths of seismic sequence boundaries that were tested by comparison with major core surfaces, downhole and core logs, and synthetic seismograms. Using sonic velocity (core and downhole), core density, and synthetic seismograms, we show that sequence boundaries correspond with acoustic impedance contrasts, although other stratal surfaces (e.g., maximum fl ooding and transgressive surfaces) also produce refl ections. Core data are suffi cient to link seismic sequence boundaries to impedance contrasts in 9 of 12 instances at Site M27, 6 of 11 instances at Site M28, and 8 of 14 instances at Site M29. Oligocene sequences have minimal lithologic and seismic expression due to deep-water locations on clinoform bottomsets. Miocene sequences (ca. 23-13 Ma) were sampled across several unconformity clino-thems (prograding units) on topset, foreset, and bottomset locations. Excellent recovery allows core-seismic integration that confi rms the hypothesis that unconformities are a primary source of impedance contrasts. Our core-seismic-log correlations predict that key seismic surfaces observed in other sub surface investigations without core and/or well logs are stratal surfaces with sequence stratigraphic signifi cance.

We present seismic, core, log, and chronologic data on three early to middle Miocene sequences (m5.8, m5.4, and m5.2; ca. 20-14.6 Ma) sampled across a transect of seismic clinothems (prograding sigmoidal sequences) in topset, foreset, and bottomset locations beneath the New Jersey shallow continental shelf (Integrated Ocean Drilling Program Expedition 313, Sites M27-M29). We recognize stratal surfaces and systems tracts by integrating seismic stratigraphy, lithofacies successions, gamma logs, and foraminiferal paleodepth trends. Our interpretations of systems tracts, particularly in the foresets where the sequences are thickest, allow us to test sequence stratigraphic models. Landward of the clinoform rollover, topsets consist of nearshore deposits above merged transgressive surfaces (TS) and sequence boundaries overlain by deepening-and fi ning-upward transgressive systems tracts (TST) and coarsening-and shallowing-upward highstand systems tracts (HST). Drilling through the foresets yields thin (<18 m thick) lowstand systems tracts (LST), thin (<26 m) TST, and thick HST (15-90 m). This contrasts with previously published seismic stratigraphic predictions of thick LST and thin to absent TST. Both HST and LST show regressive patterns in the cores. Falling stage systems tracts (FSST) are tentatively recognized by seismic downstepping, although it is possible that these are truncated HST; in either case, these seismic geometries consist of uniform sands in the cores with a blocky gamma log pattern. Parasequence boundaries (fl ooding surfaces) are recognized in LST, TST, and HST. TS are recognized as an upsection change from coarsening-to fi ning-upward successions. We fi nd little evidence for correlative conformities; even in the foresets, where sequences are thickest, there is evidence of erosion and hiatuses associated with sequence boundaries. Sequence m5.8 appears to be a single million-year-scale sequence, but sequence m5.4 is a composite of 3 ~100-k.y.-scale sequences. Sequence m5.2 may also be a composite sequence, although our resolution is insuffi cient to demonstrate this. We do not resolve the issue of fractal versus hierarchical order, but our data are consistent with arrangement into orders based on Milankovitch forcing on eccentricity (2.4 m.y., 405 and 100 k.y. cycles) and obliquity scales (1.2 m.y. and 41 k.y.).