Alluvial fan development and morpho‐tectonic evolution in response to contractional fault reactivation (Late Cretaceous–Palaeocene), Provence, France

Abstract

Along-strike variability within a Late Cretaceous to early Palaeocene contractional growth structure and associated alluvial fan deposits is documented at the northern margin of the Arc Basin (Provence, SE France).This contribution shows that alluvial fans can be used as high-resolution proxies to reconstruct structural segmentation and palaeo -geomorphological evolution of a source/basin margin system. Facies-based reconstruction allows the spatial and temporal distribution of alluvial fan bodies to be mapped. Relationships between fan area and catchment size from modern alluvial fan systems were used to estimate palaeo -catchment size. Combining alluvial fan morphologies with catchment area, pebble provenance analysis and growth structure reconstruction, we show that: (1) fan distribution and related depositional processes were strongly in£uenced by intrinsic parameters such as drainage basin evolution, local structural inheritance and lateral facies changes in source area lithologies; (2) Inherited structures trending N100 e¡ectively controlled the ¢rst-order location of the fold and thrust structures (Montagne Sainte-Victoire Range) and adjacent depositional areas (Arc Basin); (3) Syn-sedimentary faults trending N010-030 in£uenced the source/basin margin development and interacted with developing growth structures; (4) Facies changes in Jurassic carbonates controlled fold development and consequently the structural evolution of the source area; and (5) the N010-030 faults and along-strike variability of the source/basin margin system were ultimately controlled by basement structures that controlled where Late Cretaceous deformation nucleated.The overall architecture of the source/basin margin system re£ects segmentation and strain partitioning along strike, as demonstrated by diachronous alluvial fan distribution.

3D structural modelling of small-deformations in poly-phase faults pattern. Application to the Mid-Cretaceous Durance uplift, Provence (SE France)

“…Bergerat, 1985;Gattacceca et al, 2007;Hippolyte et al, 1993;Séranne, 1999). Synchronously, during the early Miocene, Alpine compression weakly reactivated PyreneoProvencal thrusts and folds (Champion et al, 2000;Leleu et al, 2009). Although the Allauch massif escaped major Pyrenean and Alpine compressive deformation, the tertiary tectonic episodes moderately overprinted the low amplitude deformations of the Durance uplift.…”

Structural style and evolution of the Pyrenean-Provence thrust belt, SE France

“…The thickness of the continental series reaches~1200 m in the depocentre of the Arc basin. Provence foreland deposits are locally characterized by Upper Campanian to Danian syntectonic breccias recording the growth and uplift of some structures such as the Nerthe, Sainte-Baume, Etoile or the Sainte-Victoire units [Durand and Tempier, 1962;Corroy et al, 1964;Angelier, 1971;Tempier and Durand, 1981;Chorowicz and Ruiz, 1984;Guieu et al, 1987;Corroy and Philip, 1964;Leleu, 2005;Leleu et al, 2005Leleu et al, , 2009Espurt et al, 2012] ( fig. 1).…”

“…In the study area, late Cretaceous-Paleocene syntectonics deposits are found in the northern flank of the Sainte-Baume thrust system, on both sides of the Sainte-Victoire unit and near the southern flank of the Vautubières anticline [e.g. Corroy and Philip, 1964;Leleu, 2005;Leleu et al, 2009;Espurt et al, 2012].…”

“…7). The Sainte-Victoire unit is a widespread dissected anticline with along-strike structural and syntectonic sedimentation variations [Leleu et al, 2009;Espurt et al, 2012]. The eastern Sainte-Victoire unit consists of two "en échelon" breakthrough fault-propagation folds mainly constituted by Jurassic rocks: the SainteVictoire and Sambuc anticlines, characterized by N-vergent thrusting towards the Jouques syncline [Chorowicz et al, 1989] The Mirabeau-Vautubières thrust system consists in two oppositely verging structures ( fig.…”

Pre-Pliocene tectonostratigraphic framework of the Provence continental shelf (eastern Gulf of Lion, SE France)

“…Mattauer, 1968;Roure and Choukroune, 1998;Bestani et al, 2015]. In Provence, a thick continental succession (~1200 m at the depocentre of the Arc basin), of late Santonian to Lutetian age, deposited in a foreland setting [Leleu et al, 2009]. During the Late Eocene (Bartonian) a major phase of shortening occurred with north-verging fold and thrust development, overprinting the former stuctures [e.g.…”