Basin growth and filling model. The basin growth model assumes that the length of the border fault (heavy black line) increases as the displacement on the fault increases. Therefore, the rift basin increases in depth, length, and width through time, causing the incremental basin capacity (accommodation space) to increase through time. The basin-filling model also assumes a constant supply of sediment and water through time.
The model is shown in five stages. For each stage, a map view, transverse cross section, and longitudinal cross section are shown. Transparent blue shows the extent of the lake, when present. The model predicts initial fluvial sedimentation (Stages 1 and 2), followed by shallow-water (Stage 3) then deep-water (Stage 4) and then shallow-water (Stage 5) lacustrine sedimentation. Basin growth and filling result in onlap of synrift units onto prerift rocks.
Stage 1A corresponds to Case 1 in the previous figure. Stage 2A corresponds to Case 2 in the previous figure. Case 3 from the previous figure is intermediate between Stage 2B and Stage 3.
Modified from Schlische and Anders (1996).