The evolution of catchment?depositional system relationships on the dip slopes of intra?rift basement highs: An example from the Frøya High, Mid?Norwegian rifted margin

Basement highs form one of many potential sediment source areas during the evolution continental rifts and rifted margins add to topographic complexity typical active rifts. Footwall basement acting as a area sedimentary systems in hangingwall major faults have been documented worldwide. However, back-tilted footwall dip slopes such received comparatively little attention. Here, we investigate subsurface case study from Norwegian shelf, where catchments shallow marine syn-rift on slope are preserved due early transgression an intra-rift high. At onset Late Jurassic rifting, Frøya High emerged prominent, N-S trending, 25 km-wide high tilted towards east response several kilometres displacement along Klakk Fault Complex, normal fault zone at High's western edge. Using well-calibrated 3D seismic reflection data, observe series conspicuous Upper wedges eastern edge margin Froan Basin. Internally, these show sigmoidal geometries marking top foresets clinoform packages with maximum thickness ca. 200 m between 30 high, dipping 10° east, southeast northeast. We interpret represent eastward prograding deltas positioned constructional shoreline, connected E-W trending valleys river up-dip. The strong progradation, interpreted reflect impact continued uplift their prior abrupt termination supply drainage capture by scarp drainages. presence connected, largely shoreline has implications for distribution around High, providing primary input longshore-driven Draugen Ridge north. Comparisons other highlight broadly similar but shows distinct lack protracted backstepping observed systems. postulate that different structural configurations systems, being or subsidence driven, may drive strongly progradational character deltaic High. example highlights need constrain points aid interpretation volumetrically significant, short-lived subtle depositional especially within complex, tectonically settings.