Tectonic evolution and sedimentological characterisation of normal fault-controlled deposits

Fault-controlled sedimentary systems develop along tectonically active basin margins, and they might preserve the transition from texturally immature to more organised deposits, representing the evolution from unsteady- to steady-state conditions. The stratigraphic and sedimentological analysis of fault-controlled deposits helps constrain the evolution of the basin in terms of tectonic events and base-level changes. This work aims to improve the understanding of the effects of footwall erosion and the growth of basin-bounding normal faults on normal fault-controlled deposits stratigraphic and along-strike architectural variability. To do so, I performed field and subsurface stratigraphic and sedimentological analyses, including geometrical and volumetric approaches. These methods allowed me to determine (i) the factors that control the development of footwall erosion complexes, (ii) temporal and spatial changes in the contribution of footwall erosion to fault-controlled deposits, (ii) the relation between periods of enhanced fault activity and the characteristics of the resultant deposits, and (iv) how the style of normal fault growth controls changes in the stratigraphic and architectural variability of fault-controlled deposits.
This work improves the understanding of the role that footwall erosion exerts on fault-controlled deposits stratigraphic and architectural variability by revealing: the conditions needed to enhance footwall erosion processes and how the degraded products are sourced and generally accumulated within texturally immature fault-controlled base-of-scarp deposits; the factors that control at a rifted margin scale the magnitude and style of footwall erosion helping to predict where base-of-scarp deposits are most likely to develop. Moreover, this work helps discriminate between models of fault growth by analysing the stratigraphical and architectural variability of fault-controlled deposits that develop during steady-state conditions (i.e., shelf- and Gilbert-type deltas), inferring that displacement and accommodation variations along normal faults control the loci and depositional architecture of steady-state normal fault-controlled deposits.