Allochthonous salt advance recorded by the adjacent syn-kinematic sedimentation: Example from the Les Avellanes diapir (South Central Pyrenees)

This work aims to present the Les Avellanes diapir as a field analog inquire how origin, advance, and emplacement of an allochthonous salt body in continental settings influence local sedimentation terms facies distribution, sediment provenance, stratigraphic relationships. At frontal part South-Central Pyrenean fold-and-thrust belt (Spain), is outcropping structure made Triassic evaporites, lutites carbonates. diapir's western boundary, structurally controlled sub-basin presents well-preserved, early Oligocene age, mixed clastic-evaporitic sedimentary sequence which recorded lateral extrusion its sheet. To define events processes by adjacent sequences, unravel evolution nature contact at study area, we have combined sedimentary, petrologic, data. Three sections been built, from 8 lithostratigraphic associations described, interpreted, correlated across sub-basin. The deformation within deposit also described interpreted together with rocks. A prograding alluvial colluvial system associated piercing salt, was exposed surface towards NE area dissolution resulting formation caprock stacks stringers intrasalt carbonates dolerites layers. ongoing uplifting caused incision drainage network, marked paleo-relief sequence, filled syn-kinematic breccias derived erosion, transport, caprock. headward erosion reached underneath caprock, triggering extrusion. Thus, flowed southwards, favored topography, overriding breccia deposit. Foliation other shear-related structures are observed megabreccia remnants overlap along base sheet These were probably formed during advance data acquired this allows for conceptualization relative movement front settings. Salt supply rates compared topographic slope, sedimentation, major controlling parameters advance. combinations expressed progradation, aggradation, retrogradation proximal over distal facies.