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<div>From the Maaslrichtian up to the Early Eocene, the Julian (or&nbsp;Slovenian) Basin is characterized by a mixed siliciclastic/carbonale&nbsp;deposits system which exhibit complex sedimentalion patterns&nbsp;depending on various controls: sea level changes; tectonic movements&nbsp;in both carbonate platform and northern source areas; subsidence;&nbsp;proximity/distality to siliciclastic, calciclastic, allodapic&nbsp;(carbonate) sediment source areas; abundance of terrigenous detritus;&nbsp;paleomorphology of the slope of the Friuli Platform, the main&nbsp;source of carbonate detritus. The depositional sequences ofthe Julian&nbsp;Basin are the result of these controls and their interaction.&nbsp;</div><div>Herein the examination of the stratigraphic sections is restricted</div><div>to the Middle Paleocene up to the Early Eocene ("Flysch di Masarolis"</div><div>and "Flysch del Grivo"),where the most important carbonate megabeds</div><div>are recognized. Fourteen stratigraphic sections of the "turbidites with</div><div>megabeds" sequence were examined (mainly along the N-S direction).</div><div>All sections are located near the southern margin of the basin,</div><div>at the foot of the slope of the north-eastern edge of the Friuli Platform.</div><div>Comparison of log s revealed marked differenoes in the thickness</div><div>of the megabeds and of the interbedded calciturbidites and siliciclaslic</div><div>turbidites. This could be ascribed to the proximity to the source areas</div><div>of mega beds and to the abrupt stope morphology.</div><div>By means of the litho-biostratigraphic analysis of the sedimeents</div><div>which filled the Julian Basin, the provenances from the main source</div><div>areas are outlined. The prevailing calciclastic detrilus (CE ,I) mixed</div><div>with allodapic carbonate sediments (CI) came from the South;</div><div>siliciclastic detritus (N CE) mixed with other calciclastic detritus (CE,</div><div>II) from N, NW as consistently indicated by paleocurrent directions;</div><div>minor (and late) mixed carbonate sediments (CE, ill) came from NE.</div><div>A rough sedimentary balance comprising megabeds, thick beds,</div><div>multisource turbidites (siliciclastic, carbonate, mixed plus couplets)</div><div>is calculated.</div><div>An attempt to apply the eustatic sea level curve of Haq et al. (1987)</div><div>to Maastrichtian-Paleocene and Eocene deposits of the Julian Basin</div><div>is made. Lowstands of the Maastrichtian- Paleocene and of the Late</div><div>Ypresian are well recognizable. More problem s arise upon examining</div><div>the "Flysch del Grivo" section which is slrongly controlled by</div><div>tectonic mechanisms. The triggering mechanisms for mega bed emplacement&nbsp;in the Julian Basin is related to seismic activity along the</div><div>southern border of the basin. In conclusion, the "turbidites with</div><div>megabeds" sequence is integrated within the framewot;k of the geological&nbsp;evolution of the Julian Basin.</div>