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The growth- and throw-rate variability on normal faults can reflect fault interaction, plate tectonic forces, and, in gravity-driven systems, variations in sediment loading. Because earthquakes may occur as faults slip, it is important to understand what processes influence throw rate variability on normal faults to be able to predict seismic hazards in extensional terranes. Furthermore, the rate of normal fault growth directly controls rift physiography, sediment erosion, dispersal and deposition, and the distribution and stratigraphic architecture of synrift reservoirs. Instrumental (e.g., geodetic) data may constrain the coseismic movement on, or relatively short-term (i.e., <103 yr) throw rate history of, normal faults, whereas paleoearthquake data may provide important information on medium-term (i.e., 103–105 yr) rates. Constraining longer term (i.e., >106 yr) variations typically requires the use of seismic reflection data, although their application may be problematic because of poor seismic resolution and the absence of, or poor age constraints on, coeval growth strata. In this study, I use 3-D seismic reflection and borehole data to constrain the growth and (minimum) long-term throw rate variability on a gravity-driven, salt-detached normal fault (Middle–Late Jurassic) in the South Viking Graben, offshore Norway. Using these data, I recognise five main kinematic phases: (1) Phase 1 (early Callovian)—fault initiation and a phase of moderate fault throw rates (0.06 mm yr−1); (2) Phase 2 (early–end Callovian)—fault inactivity, during which time the fault was buried by sediment; (3) Phase 3 (early–late Oxfordian)—fault reactivation and a phase of moderate throw rates (up to 0.03 mm yr−1); (4) Phase 4 (latest Oxfordian)—a marked increase in throw rate (up to 0.27 mm yr−1); and (5) Phase 5 (early Kimmeridgian–middle Volgian)—a decline in throw rate (0.03 mm yr−1) and eventual death of the fault. These rates are comparable to those observed on other gravity-driven normal faults, with the variability in this example apparently kinematically coupled with the growth history of the thick-skinned, basin-bounding normal fault system. Fluctuations in sediment accumulation rate and loading may have also influenced throw rate variability. Shallow-marine reservoirs deposited when throw rate was relatively low (Phase 1) increase in thickness but do not change in facies across the fault, principally because sediment accumulation rate outpaced fault throw rate. In contrast, deep-marine turbidite reservoirs, despite being characterized by relatively high sediment accumulation rates, were deposited when the throw rate was relatively high (Phase 4), thus are only preserved in the fault hanging wall. Variations in throw and sediment accumulation rate may therefore act as dual controls on the thickness and distribution of synrift reservoirs in salt-influenced rift basins.

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