Deformation–sedimentation feedback and the development of anomalously thick aggradational turbidite lobes: Outcrop and subsurface examples from the Hikurangi Margin, New Zealand

摘要: Concepts of the interaction between autogenic (e.g., flow process) and allogenic tectonics) controls on sedimentation have advanced to a state that allows controlling forces be distinguished. Here we examine outcropping subsurface Neogene deep-marine clastic systems traversed Hikurangi subduction margin via thrust-bounded trench-slope basins, providing an opportunity interplay structural deformation sedimentation. Sedimentary logging mapping Miocene outcrops from exhumed portion wedge record heavily amalgamated, sand-rich lobe complexes, up 200 m thick, which accumulated behind NE–SW-oriented growth structures. There was no significant deposition low-density parts gravity flows in basin center, although lateral fringes demonstrate fining thinning indicative deposits flows. Seismic data offshore show analogous lobate reflector geometries. These accumulate into complexes 5 km wide, 8 long, 300 comparable scale with lobes this margin. Mapping reveals are vertically stacked thrusts. results illustrate repeated trapping sandier turbidity currents form aggradational finer-grained suspended load bypassing areas downstream. However, development characterized by partial bypass implies feedback mechanism operates perpetuate confinement condition, rejuvenation accommodation. The proposed is coupling sediment loading rate, such load-driven subsidence focuses stress basin-bounding faults perpetuates generation accommodation basin, hence modulating tectonic forcing. Recognition has implications for understanding tectono-stratigraphic evolution fold thrust belts distribution resources within them.