# A mud-filled submarine canyon cutting through a sand-prone turbidite succession: A Lower Oligocene field analogue of stratigraphic-structural trap in the Western Alpine Foreland Basin, France

Louison Mercier, Sébastien Migeon, Jean-Loup Rubino, Yamirka

Rojas-Agramonte, Anna Hagen, Romain Bousquet, Regina Mertz-Kraus

► To cite this version:

Louison Mercier, Sébastien Migeon, Jean-Loup Rubino, Yamirka Rojas-Agramonte, Anna Hagen, et al.. A mud-filled submarine canyon cutting through a sand-prone turbidite succession: A Lower Oligocene field analogue of stratigraphic-structural trap in the Western Alpine Foreland Basin, France. Marine and Petroleum Geology, 2025, 183, pp.107620. 10.1016/j.marpetgeo.2025.107620. hal-05450103

HAL Id: hal-05450103

https://hal.science/hal-05450103v1

Submitted on 9 Jan 2026

HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d'enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés.

<figure><img src="image_1.png" /></figure>
<figure><img src="image_2.png" /></figure>

# A mud-filled submarine canyon cutting through a sand-prone turbidite succession: A Lower Oligocene field analogue of stratigraphic-structural trap in the Western Alpine Foreland Basin, France

Louison Mercier<sup>a,b,*</sup> ID, Sébastien Migeon<sup>a,c</sup>, Jean-Loup Rubino<sup>c</sup>, Yamirka Rojas-Agramonte<sup>d</sup>, Anna Hagen<sup>e</sup>, Romain Bousquet<sup>e</sup>, Regina Mertz-Kraus<sup>d</sup>

## ARTICLE INFO

### Keywords:

- Submarine canyon

- Mud-filled canyon

- Schistes à Blocs Formation

- Annot Sandstones Formation

- Turbidites

- Debrites

- Combination trap

- Lower Oligocene

- Provenance

## ABSTRACT

Submarine canyons are key elements of the evolution of convergent margins. Their infilling can be mud-prone and thus represents a good seal if they cut through reservoir series, this erosion phase may be enhanced by tectonic activity. The present study focuses on the Western Alpine Foreland Basin where we use the outcrops of the Schistes à Blocs Formation to study the syn-tectonic evolution of a Lower Oligocene submarine canyon that cuts through the Annot Sandstones Formation. The Intra Schistes à Blocs Erosion Surface (ISaBES) has been mapped in the field. Airborne and drone pictures were also used. Moreover, the deposition model and the stratigraphic architecture of the canyon-fill were reconstructed from the analysis of seven sedimentary logs cumulating 410 m of series, particularly crossing the under described Schistes Bruns Member. The sedimentary system of this lower unit of the canyon-fill has been also constrained by the measurement of paleocurrents, and the provenance analysis of detrital zircons from four samples. The paleocurrent measurements on the unidirectional ripples deposited within the Schistes Bruns Member is witness of a turbulent flow rebound against the steep northern flank of the canyon, during the construction of internal levees which often experimented gravity collapse. Slumping of internal levees improves the seal properties of the canyon-fill, while the canyon thalweg was dominated by by-pass processes. Detrital zircons reveal that the provenance of the Schistes Bruns Member is sourced by the same sedimentary system of the Annot Sandstones Formation. Thus, we interpreted that both the canyon excavation and the sediment by-pass within its thalweg during the deposition of the Schistes Bruns Member, were triggered by an increase in basin slope related to the tectonic evolution of the accretionary prism. Finally, the ISaBES is a composite and diachronous surface resulting both from the morphology of the internal levees, and from their reworking during the deposition of the olistostromes of the Schistes à Blocs Exotiques Member, that predates the emplacement of the Alpine nappes within the foreland basin.

## 1. Introduction

Submarine canyons are erosive conduits which typically exhibit stepped sides, and which transport particles from the continental shelves to the abyssal plains (Menard, 1955; Normark and Carlson, 2003; Shepard, 1981). They incise both passive and active continental margins of

most of the world's oceans (Bührig et al., 2022; Harris and Whiteway, 2011; Shepard, 1972; Shepard and Dill, 1966). Canyon formation and evolution are often the result of multiple processes (Shepard, 1981), which may act in concert or alternate to excavate and refresh the canyons axis (Pratson et al., 1994; Pratson and Coakley, 1996; Shepard, 1981; Mulder et al., 2012; Trincardi et al., 2007). Eustatic falls has long been considered as the key factor in canyon initiation and evolution

<footnote><sup>a</sup> Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, IRD, Géoazur, 250 rue Albert Einstein, 06560 Valbonne, France</footnote>

<footnote><sup>b</sup> Mines Paris-PSL University, Centre de Géosciences, Equipe Géologie, 35 rue Saint-Honoré, Cedex, 77305, Fontainebleau, France</footnote>

<footnote><sup>c</sup> Sorbonne Université, 75005 Paris, France</footnote>

<footnote><sup>d</sup> Institut für Geowissenschaften, Johannes Gutenberg Universität, Johann-Joachim-Becher-Weg 21, 55128 Mainz, Germany</footnote>

<footnote><sup>e</sup> Institut für Geowissenschaften, Petrologie und Geodynamik, Christian-Albrechts-Universität zu Kiel, Ludewig-Meyn-Straße 10, R. 454, 24118 Kiel, Germany</footnote>

<footnote>* Corresponding author. Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, IRD, Géoazur, 250 rue Albert Einstein, 06560 Valbonne, France.</footnote>

<footnote>E-mail addresses: louison.mercier@minesparis.psl.eu (L. Mercier), migeon@geoazur.unice.fr (S. Migeon), jean-loup.rubino@wanadoo.fr (J.-L. Rubino), yamirka.rojas@geow.uni-heidelberg.de (Y. Rojas-Agramonte), anna.hagen@ifg.uni-kiel.de (A. Hagen), romain.bousquet@ifg.uni-kiel.de (R. Bousquet), regina.mertz@uni-mainz.de (R. Mertz-Kraus).</footnote>
Abbreviations

FA: Facies Association

ISaBES: Intra Schistes à Blocs Erosion Surface

MTD: mass transport deposit

(Baztan et al., 2005; Rasmussen, 1994). However, the formation of some canyons during high sea levels implies triggering by other factors such as active tectonism (Clayton and Olariu, 2022; Fulthorpe et al., 2000; Park et al., 2019).

Canyon evolution is associated with one or more cut-and-fill sequence(s) (Baztan et al., 2005; Collot et al., 2019; Ding et al., 2013; Ferry et al., 2004; Galloway et al., 1991; Gong et al., 2011; Goodwin and Prior, 1989; Hsieh et al., 2020; Liu et al., 1993; Mercier, 2022; Mercier et al., 2021). On active margins, cut-and-fill sequences can be directly related to deformation phases of the accretionary prism (Hsieh et al., 2020; Park et al., 2019; Ratzov et al., 2012). Canyon-fills can be mainly composed of clays, which are generally associated with distal pro-gradation deltas and/or destabilizations of delta front (Clayton, 2017; Galloway et al., 1991; Goodwin and Prior, 1989; Mercier, 2022; Mercier et al., 2021; Posamentier et al., 1991), and/or associated with shaly hemipelagic drapes due to periods of lower gravity-flow activity (Gong et al., 2011; Mercier, 2022) or canyon abandonment (Clayton, 2017; Goodwin and Prior, 1989; Jobe et al., 2011).

Past (Burke, 1972; Chuber, 1987; Peres and Arso, 1986) and recent (Dailly et al., 2002; Effimoff and Keall, 2018; McGee et al., 2017; Park et al., 2019; Sneider, 2013) oil and gas discoveries show that mud-filled canyons can provide a very efficient upper and/or lateral seal for trun-cated sand-prone reservoirs, forming stratigraphic traps named « bur-ied-hills » (Allan et al., 2006; Amy, 2019; Dolson et al., 2017). Those traps are often associated with extensive or compressive deformation, either by sealing structures (Orife and Avbovbo, 1982) or by undergoing syn-sedimentary or subsequent deformation (Brownfield, 2016; Cock-erill, 2019; Cornish and Lambiotte, 2016; Dailly et al., 2002; Matesic, 2012; Mercier et al., 2021; Sneider, 2013). Consequently, they often constitute the stratigraphic component of combination traps (Mercier, 2022; Mercier et al., 2021). In such setting, oil companies may be interested in characterizing: 1) the controlling factors triggering canyon formation and its evolution by mud-plugging, 2) and/or the sedimentary properties of the seal which may represent a high risk of leakage if it contains sand-prone sedimentary bodies (Clayton and Olariu, 2022; McGee et al., 2017; Mercier et al., 2021; Park et al., 2019). Nevertheless, the 3D architecture and the depositional model of deeply buried mud-prone canyon-fill cannot be precisely described from subsurface studies due to: 1) the limited vertical resolution of seismic data at depth, and/or 2) the difficulty of correlating wells in mud-prone bodies, particularly when they are several kilometers apart. Only field studies of ancient analogs, such as the one presented in this paper, can provide a clear picture of the multiscale architecture of such geological features.

This study focuses on the Schistes à Blocs Formation that filled-up the submarine-canyon system cutting through the Annot Sandstones Formation (Jean et al., 1985; Mercier et al., 2024), located in the internal part of the Western Alpine Foreland Basin, more precisely in the San-guinière-Restefond Sub-Basin (Fig. 1). However, although the descrip-tion of the Schistes à Blocs Formation was initiated decades ago (Jean et al., 1985; Kerckhove, 1969, 1975), details are still lacking regarding the sedimentary facies that constitute this mud-prone series, particularly concerning the lower unit i.e. the Schistes Bruns Member. Thus, we managed to understand in which environments the sedimentation took place, and which depositional processes were involved during the canyon infilling. Moreover, the influence of canyon morphology on its internal stratigraphic architecture was specially constrained in this study. We also defined the nature of the surface named Intra Schistes à

Blocs Erosion Surface (ISaBES), which separates the two members of the Schistes à Blocs Formation. These observations are clues for the under-standing of submarine-canyon evolution, and they also permit us to clarify how evolved the Western Alpine Foreland Basin during the Lower Oligocene. Thus, this work provides new constraints about submarine-canyon infillings and their related processes. It also provides a superb field example for subsequent exploration in petroleum prov-inces presenting similar combination trap(s), where resolution of seismic 3D data is not high enough to image the vertical and lateral associations of sedimentary facies and the internal architecture of the muddy infilling.

## 2. Geological setting

The large scale flexure of the European Plate which triggered the creation of the Western Alpine Foreland Basin (Fig. 1A) began during the Middle Eocene, when the alpine collision was initiated (Ford and Lick-orish, 2004; Schmid et al., 1996). The regional subsidence progressively propagated westward (Ford and Lickorish, 2004) and thus controlled the diachronous Nummulitic Transgression which propagated following the same direction (Campredon, 1972; Sztrákos and du Fornel, 2003). During the Upper Eocene, the Mesozoic sedimentary cover of the basin was progressively affected by a westward folding, tens of kilometers in wavelength (Ford and Lickorish, 2004), that triggered the partitioning of the foreland into NW-SE to NNW-SSE oriented synclines (Apps, 1985; Elliott et al., 1985; Jean, 1985; Joseph and Lomas, 2004; Ravenne et al., 1987). The latter consists of at least four parallel and disconnected sub-basins, several tens of kilometers long and few tens of kilometers wide (Ravenne et al., 1987; du Fornel et al., 2004; Joseph and Lomas, 2004, Fig. 1A). The southern edge of the foreland is bounded by the uplift of the Maures-Estérel and the Corsican-Sardinian Massifs due to the continuation of the East Iberian Orogen, which promoted terrige-nous inputs within the basin (Ford and Lickorish, 2004; Jean, 1985).

Thus, during the Eo-Oligocene transition, sub-basins were succes-sively formed and filled diachronously. Shallow environments formed a low-angle and relatively low-energy carbonate ramp (Apps et al., 2004; Sinclair et al., 1998; Van de Vyver et al., 2024) which led to the depo-sition of the Calcaires Nummulitiques Formation, succeeded by slope and bathyal deposits of the Marnes Bleues Formation (Ravenne et al., 1987, Fig. 1B) when local subsidence rate abruptly increased (Ford et al., 2006; Ford and Lickorish, 2004; Jean, 1985). Deposition of car-bonates and marls was followed by the emplacement of a siliciclastic ramp only supplied by southern fan deltas, leading to the deposition of the turbidites of the Grès d'Annot/Annot Sandstones Formation (du Fornel et al., 2004; Jean, 1985; Joseph and Lomas, 2004; Joseph and Ravenne, 2001) as mapped in Fig. 1A. The latter were initiated with the lobe fringe facies of the Marnes Brunes Inférieures Member (Inglis et al., 1981; Joseph and Lomas, 2004; Ravenne et al., 1987). In northern-most sub-basins, a similar facies sealed the series (Marnes Brunes Supérieures Member, Fig. 1B) (du Fornel, 2003; Etienne et al., 2013; Inglis et al., 1981; Joseph and Lomas, 2004; Kerckhove, 1969; Ravenne et al., 1987).

The Sanguinière-Restefond Sub-Basin is located on the northwestern edge of the Argentera Massif (Fig. 1A). It is filled by a 900 m-thick Annot Sandstones (turbidite lobes) series (Jean, 1985; Jean et al., 1985), mainly deposited during biozone NP21 of the Rupelian (Sztrákos and du Fornel, 2003). Then the Annot Sandstones were locally deeply eroded under marine conditions by a canyon network called the La Bonette Canyon (Mercier et al., 2024). The latter is few kilometers wide, about 6 km long, and cuts 700 m-deep through the Annot Sandstones Formation (Jean et al., 1985; Mercier et al., 2024, Fig. 2). The canyon is East-West oriented due to the syn-sedimentary control by N80°E normal faults (Bouroullec et al., 2004; Lansigu, 2000; Mercier et al., 2024), and its sedimentary infilling consists of the Schistes à Blocs Formation (Jean et al., 1985; Mercier et al., 2024, Fig. 2). The latter is composed of two units: (1) the basal Schistes Bruns, made of shales and thin-bedded turbidites, overlaid by (2) the olistostromes of the Schistes à Blocs
<figure><img src="image_3.png" /><figcaption>**Fig. 1.** (A) Simplified geological map of the Western Alpine Foreland Basin (redrawn after Rouire and Blanc, 1979; Kerckhove and Monjuvent, 1980; Rouire et al., 1980b; a) and modified after Mercier et al. (2024). Location of Fig. 2 is also shown. Paleocurrents data are from Joseph and Lomas (2004), Ravenne et al. (1987) and Vinnels et al. (2010a). Abbreviations: A, Annot; Al, Allos; B, Barrème; Bar, Barcelonnette; Br, Braux; Bor, Bordighera; C, Contes; Cas, Castellane; D, Devoluy; EC, eastern Champsaur, GC, Grand Coyer; L, Lauzanier; M, Menton; MT, Mont Tournairet; QC, Quatre Cantons; PC, Peira Cava; SA, Saint-Antonin; SE, Saint-Etienne de Tinée; SR, Sanguinière-Restefond; TE, Trois Evêchés; TH, Trois Hommes, Tor, Tortissa; Tr, Triora; O, Orcières; V, Vintimiglia; WC, western Champsaur. (B) Schematic lithostratigraphic chart of the Western Alpine Foreland Basin (modified after Joseph and Lomas, 2004; Ravenne et al., 1987) and corresponding chronostratigraphic chart (modified after Mercier et al., 2024; Joseph et al., 2012; Sztrákos and du Fornel, 2003. (C) Location of Fig. 1A within France and Italy.</figcaption></figure>
<figure><img src="image_4.png" /><figcaption>**Fig. 2.** Simplified geological map of the study area which exhibits La Bonette Canyon, the stratigraphy of its infilling, and its longitudinal control by the Colombart Structure, the last is composed of faults F1 to F6 (modified after Mercier et al., 2024; Bouroullec et al., 2004; Jean, 1985; Kerckhove et al., 1974). See Fig. 2 for location.</figcaption></figure>
Exotiques (Kerckhove, 1975; Inglis et al., 1981; Jean, 1985). These two units were recently defined as members (Mercier et al., 2024). Deposition of the Schistes à blocs Formation in the Sanguinière-Restefond Sub-Basin occurred during biozones NP22-23 of the Lower Rupelian (Mercier et al., 2024). The Schistes à Blocs Formation was finally thrusted by the Embrunais-Ubaye nappes (Fig. 1B). Those nappes mainly consisted of Helminthoïd Flysch which was initially deposited within the Ligurian-Piemontese Basin, during Upper Cretaceous to Paleocene times (Kerckhove, 1969). The emplacement in marine environment of the Autapie nappe (i.e. the lower Embrunais-Ubaye nappe) is supposed to occur also during the Rupelian, which terminates the sedimentary record of the inner part the foreland basin (Kerckhove, 1969, 1975).

# 3. Data and methods

## 3.1. Field surveys

We completed the revisited geological map of the Bonette-Restefond area (Fig. 2; Mercier et al., 2024). We mapped with precision for the first time the Intra Schistes à Blocs Erosion Surface (Fig. 2), using i) a Garmin© GPS, and ii) aerial photographs with horizontal resolution of 0.20 m from the IGN (i.e. Institut Géographique National). Then, we measured in the field with a compass equipped with a clinometer the paleocurrent directions within the Schistes à Blocs Formation from unidirectional current ripples. The paleocurrent directions were compiled using Georose©.

## 3.2. Facies analysis and sedimentary logging

In order to describe the facies and the stratigraphic architecture of the Schistes à Blocs Formation, particularly within its lower member (i. e. Schistes Bruns Member), we made seven sedimentary logs (Sab27-Sab33) which are located in the eastern part of the La Bonette Canyon (Fig. 2), more precisely on the northern flank of the canyon. We also conducted the stratigraphic correlation of these sedimentary logs (see Fig. 10 for more details). Sedimentary logs cumulate 410 m of logging using a home-made Jacob's staff with a vertical precision of ≈5 cm. Logging generally starts at the Grès d'Annot Upper Erosion Surface which is onlapped by the canyon-fill (Mercier et al., 2024). The sedimentary logs were also geo-referenced using a field GPS and integrated into the GIS project (Fig. 2).

## 3.3. Detrital zircon dating by U/Pb

Four samples (Bo28b, Bo30, Bo32 and Bo33) were collected for isotopic analyses. Sample Bo28b was obtained from a very coarse-grained and metric-thick bed of sandstone (F4 facies of Mutti, 1992) of the Grès d'Annot Formation; Bo32 from a coarse-grained centimeter-thick sandstone (F9b facies, see section 4.1.1) of the Schistes Bruns Member; Bo33 from a meter-thick bed of silty mudstone (F9a-2 facies, see section 4.1.1) of the SB Fm; Bo35 from a medium-grained and pluri-decimeter- thick bed (F8 facies, see section 4.1.2).

Samples were processed at the Institut für Geowissenschaften, Christian-Albrechts-Universität zu Kiel. Approximately 1–2 kg of each sample was crushed to a grain size of ~250 µm, using a jaw crusher and roller mill. A heavy mineral fraction (mostly zircon) was obtained by panning with water and ethanol. Zircons were handpicked using a binocular microscope (Olympus SZX16) and later mounted in 1-inch epoxy resin discs. Mounted samples were polished to expose the centers of the zircons. This procedure is needed before imaging the zircons by using an electron microscope (SEM) to obtain cathodoluminescence images. Imaging with this method delivers insights into the internal structure of zircons such as inclusions, zoning, alteration, fractures, xenocrystic cores and metamictic domains. The cathodoluminescence images were used as a basis to decide which grain to analyze and where to place the spots.

Zircons were analyzed for their U and Pb isotope composition by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). The analyses were performed using an Agilent 7500ce quadrupole ICP-MS instrument coupled to an ESI NWR193 ArF excimer laser system with 193 nm wavelength equipped with a TwoVol2 ablation cell at the Institut für Geowissenschaften, Johannes Gutenberg Universität, Mainz. Analyses were conducted using spot sizes of 30 µm with 20 s warm up, 30 s dwell and 20 s wash out time. The repetition rate has been 10 Hz at energy density of 3.5 J/cm². Oxide formation rates (ThO⁺/Th⁺) were below 0.5 %. The integration times for individual mass scans were 10 ms for masses 232 and 238, 30 ms for masses 202, 204 and 208. 40 and 60 ms were used for masses 206 and 207, respectively.

Data reduction (SM. 1) was performed by using the software PepiAge (Dunkl et al., 2009) to edit the raw data. An in-house Excel™ spreadsheet was used to calculate the different ratios. Time-dependent laser- and mass-spectrometer-induced inter-element fractionation (Pb/U) as well as mass fractionation and common Pb were corrected using the same in-house spreadsheet.

Ages, uncertainties and Concordia diagrams were calculated using the Isoplot3 add-in for Excel™ (Ludwig, 2003). Concordia ages are plotted with 2σ error ellipses, and discordia intercept ages are given at 95 % confidence. Analyses were calibrated using the reference zircon GJ-1 (Jackson et al., 2004). The reproducibility was controlled by analyzing the reference zircons 91500 (Wiedenbeck et al., 1995). For ages lower than 1.0 Ga, ²⁰⁶Pb/²³⁸U ratios are used for interpretation, for ages above 1.0 Ga ²⁰⁷Pb/²⁰⁶Pb is used.

# 4. Results

## 4.1. Sedimentary facies and facies associations of the Schistes à Blocs Formation

This section provides descriptions of individual facies and facies associations as observed at several locations within the Schistes à Blocs Formation, particularly within the Schistes Bruns Member, that infilled the La Bonette Canyon. We used facies classification by Mutti (1992) to reference them where possible. Each facies association is determined either from the dominant facies or from the facies that best characterizes the depositional process within the corresponding stratigraphic interval.

### 4.1.1. Marly and slumped marls facies association

F9a-1 facies is a marly mudstone organized in well-defined multi-millimeter to centimeter thick layers, resulting in platy delamination following laminae or laminae sets (Fig. 3A). The weathering patina of the deposits is brown or yellow ochre, giving its characteristic color to the Schistes Bruns Member, while its fresh patina is blue-grey (Fig. 3A). This facies constitutes the finer part of other marly and heterolithic facies.

F9a-2 facies is a silty mudstone with no internal structure, occurring in the form of rare lenticular beds with a pronounced brown weathering patina. The beds are multi-decimetric to metric in thickness and multi-decametric in extent. They are isolated within marly units of type F9a-1 or F9a-3 (Fig. 3A).

F9a-3 facies is a mixing between the two facies previously described (Fig. 3B). The silty layers show a yellow patina, including on the fresh breaks. They represent less than 10 % of the volume of this facies.

F9a-4 facies is similar to the F9a-1 facies but it differs from its location as it only onlaps metric deep depressions located directly on the Grès d'Annot Upper Erosion Surface. It consists of individual black and bioturbated silty-clayey beds about 10 cm thick, overlaid by an intensely bioturbated level of brown silty-clay about 20 cm thick (Fig. 3D). It shows ferromagnesian crusts as described by Ravenne et al. (1987), and some subhorizontal burrows (Fig. 3C–D). F9a-4 is interpreted as a condensed level.

The preceding facies constitute the marly facies association FA-1 (Table 1): it only consists of sedimentary facies which are variants of
<figure><img src="image_5.png" /><figcaption>**Fig. 3.** Marly facies association (FA-1) and slumped marly facies association (slumped FA-1) that constitute 80–90 % by volume of the Schistes Bruns Member. Orange card is about 10 cm long. (A) Silty mudstone bed (F9a-2 facies) which is interbedded within well layered marly mudstone (F9a-1 facies). (B) F9a-3 facies which is composed of silty mudstone of millimetric to centimetric layers interbedded within well layered marly mudstone. (C) Condensed level (T9a-4 facies) made of black silty clays and of bioturbated brown silty clays. Both commonly fill metric-deep depressions cutting through the Annot Sandstones Formation. The Grès d'Annot Upper Erosion Surface is covered by a ferromagnesian crust which exhibits tracks. GAUES, Grès d'Annot Upper Erosion Surface. (D) Close-up view of the T9a-4 facies. (E) Disturbed level of silty mudstone (F9a-1 facies) that constitutes the slumped marly facies association (slumped FA-1).</figcaption></figure>

the F9a distal facies of Mutti (1992). Fa-1 is interpreted either as hemipelagic drapes found at any places within the canyon thalweg or as fine-grained intervals that could be locally concentrated to build canyon confined levees, as observed along modern submarine canyons (Babonneau et al., 2004; Gaudin et al., 2006). FA-1 can be commonly found slumped within intervals several meters or even decameters thick. In this slumped form, silty marls are strongly indurated, with conchoidal fracture and no bedding. FA-1 and its slumped form both constitute

massive levels of metric to multi-metric thickness (Fig. 3E), and can also constitute the matrix of some debrites described in section 4.1.3. The slumped form of FA-1 is more abundant than FA-1 itself, and they represent 80–90 % of the Schistes Bruns Member (Table 1).

### 4.1.2. *Undisturbed and slumped confined levees facies association*

F9b facies consists of centimeter-thick silty to very-fine-sand turbidites, and centimeter- to decimeter-thick fine-sand turbidites. They
<caption>**Table 1**</caption>

Facies and facies associations of the Schistes à Blocs Formation, precising their respective nomenclature, relative abundance within the Schistes Bruns Member (SB Mbr) and the Schistes à Blocs Exotiques Member (SaBEx Mbr), and their relative occurrence of reworking by slumping when it applies. Interp.: interpretation.

<table><thead><tr><th>Facies association</th><th>Facies</th><th>Description</th><th>Abundance in concerned member or FA</th><th>Occurrence of reworking by slumping</th><th>Figure</th></tr></thead><tbody><tr><td rowspan="5">FA-1 i.e. marly FA</td><td>F9a-1</td><td>Marly mudstone with pluri-millimeter to centimeter-thick layers.</td><td>Very high</td><td>High</td><td>3A, 3E</td></tr><tr><td>F9a-2</td><td>Silty mudstone turbidite beds with lenticular shape and without internal structure, which are multi-decimetric to meter-thick.</td><td>Low</td><td>Low</td><td>3A</td></tr><tr><td>F9a-3</td><td>Alternance of centimer- to pluri-centimeter-thick turbidite beds of silty mudstone with marly mudstone.</td><td>High</td><td>High</td><td>3B</td></tr><tr><td>F9a-4</td><td>Black and bioturbated silty-clay level ≈10 cm-thick overlaid by intensely bioturbated brown silty-clay level ≈20 cm-thick, both forming a condensed level.</td><td>Low</td><td>Supposed null</td><td>3C, 3D</td></tr><tr><td>FA-1 interp.</td><td>1) Hemipelagic drapes, and 2) confined levees of distal location in respect to the canyon axis.</td><td>Very high (80-90 %) in SB Mbr, absent in SaBEx Mbr</td><td>High</td><td>3</td></tr><tr><td rowspan="6">FA-2 i.e. heterolithic FA</td><td>F9b</td><td>Centimeter-thick silty to very-fine-sand turbidites, and centimeter- to decimeter-thick fine-sand turbidites without internal structure, interbedded with marly mudstone.</td><td>High</td><td>High</td><td>4A</td></tr><tr><td>F9a-5</td><td>Decimeter-thick beds of very fine-sand turbidites with convolutes (Tc of Bouma, 1962).</td><td>Low</td><td>High</td><td>4B</td></tr><tr><td>F9a-6</td><td>Pluri-centimeter-thick beds of very fine-grained sandstone with wavy bases and tops, that exhibit unidirectional ripples always pointing toward SSW.</td><td>Low</td><td>Low</td><td>4C, 11</td></tr><tr><td>F8</td><td>Decimeter to pluri-decimeter-thick beds of medium to coarse sand, without internal structure. Beds are often amalgamated within small-scale erosive structures, and sometimes constitute the base of fining-upward sequences with F9b beds.</td><td>Low</td><td>Low</td><td>4D, 4E, 5A, 5B</td></tr><tr><td>FA-2 interp.</td><td>1) Mostly confined levees of proximal location in respect to the canyon axis, and less frequently 2) ephemerous turbiditic channels. The last are often confined within small grabens which are located on canyon terraces.</td><td>Low in SB Mbr, absent in SaBEx Mbr</td><td>High</td><td>4D, 4E, 5A, 5B</td></tr><tr><td>F0-1</td><td>Metric- to pluri-metric-long and -thick blocks of Annot Sandstones, which often show a trapezoidal shape. They show important internal deformation when they are composed of thick sandstone beds. These olistoliths are re-deposited within FA-1 or FA-2.</td><td>Low</td><td>Not applies</td><td>6A, 6B</td></tr><tr><td rowspan="3">FA-3 i.e. olistolith FA</td><td>F0-2</td><td>Metric- to pluri-metric-long and -thick blocks of Annot Sandstones that often exhibit a stratiform shape, and show few internal deformation. These olistoliths are re-deposited within FA-1 or FA-2.</td><td>Low</td><td>Not applies</td><td>6C</td></tr><tr><td>FA-3 interp.</td><td>Breccia levels of Annot Sandstones blocks fallen or slid from the canyon/tributary walls and re-deposited within confined levees or hemipelagic drapes (FA-1 or FA-2), or less frequently outrunner blocks ejected at the front of MTDs (MTD4).</td><td>Low in SB Mbr, very low in SaBEx Mbr</td><td>Not applies</td><td>6</td></tr><tr><td>F-Ex1</td><td>Angular to sub-angular clasts of allochtonous sedimentary series (i.e. turbidites and carbonates) that exhibit a yellow ocre patina, floating in a black marly matrix which is easily friable. Clast are centimer- to meter-wide and their size increases toward the top of the layers.</td><td>Low in SB Mbr, High in SaBEx Mbr</td><td>Not applies</td><td>7A</td></tr><tr><td rowspan="3">FA-Ex i.e. olistostrome FA</td><td>F-Ex2</td><td>Variant of F1-Ex1 facies with a silty-clay matrix which laterally varies into coarse-grained sandstone, matrix shows a yellow-ocre patina. Size of clasts increases vertically from sand grains to multi-decimeter-wide blocks. F1-Ex1 beds are ≈1 m-thick.</td><td>Low in SB Mbr, absent in SaBEx Mbr</td><td>Not applies</td><td>7B, 7C, 7D</td></tr><tr><td>F-Ex3</td><td>Variant of F1-Ex1 facies that exhibit multi-metric-wide blocks at the top of the beds.</td><td>High, observable only in SaBEx Mbr</td><td>Not applies</td><td>7E</td></tr><tr><td>FA-Ex interp.</td><td>Olistostromes sourced from the Autapie nappe (i.e. reworked allochtonous sedimentary series).</td><td>Low in SB Mbr, 100 % of SaBEx Mbr</td><td>Not applies</td><td>7A, 7E</td></tr></tbody></table>

show no internal structure and a short lateral extent (Fig. 4A). Turbidites are interbedded with facies F9a-1 and F9a-3 (Fig. 3A, B, 4A). F9b facies commonly exhibits a sand/clay ratio which is at most 10 %–20 % (Fig. 4A), and so can be defined as a F9b facies of Mutti (1992) with a low content of sand-size particles.

Turbidites of F9a facies are interbedded within F9b pluri-metric levels. They often exhibit decimeter-thick very-fine-sand turbidites with convolutes (Fig. 4B) and less commonly low amplitude bed waves of unidirectional ripples with foresets that are often oriented toward the SSW (Fig. 4C).

F8 facies is made up of massive medium-sand beds, decimeter- to multi-decimeter-thick. Beds are amalgamated and found within lentic-ular bodies of metric thickness and low lateral extension, which are commonly interbedded within facies F9b (Fig. 4D and E). These lentic-ular bodies can show cross-stratifications that characterize a lateral-accretion process (Fig. 4E). They are interpreted as small-scale chan-nelizing features which can be found within the infilling of the canyon axis, or at the base of shallow depressions that are controlled by small syn-sedimentary grabens, located close to the canyon axis (Fig. 4E).

The previously described turbidite facies are exclusively found within the Schistes Bruns Member (Table 1). They are mainly repre-sented by variants of facies F9a and F9b of Mutti (1992) where F9b is the most common. Facies F8 is also rarely present. They constitute the heterolithic facies association FA-2: it is interpreted as silt/sand deposits associated with confined levees. Similar turbidite facies are more commonly found strongly affected by brittle/soft deformation resulting from slumping (Fig. 5A): they are then interpreted as slumped confined levees. The latter commonly constitute decametric- to pluri-decametric-thick units (Fig. 5A and B), and so represent the second most abundant facies association identified within the Schistes Bruns Member after the marly facies association (i.e. FA-1 and slumped form of FA-1).

### 4.1.3. Olistolith facies association

Olistolith facies association (FA-3) consists of masses of Annot Sandstones remobilized and redeposited mostly within the Schistes Bruns Member, and rarely within the Schistes à Blocs Exotiques Member. The FA-3 exhibits two different types of internal organization
<figure><img src="image_6.png" /><figcaption>**Fig. 4.** Heterolithic facies of the Schistes Bruns Member that compose undisturbed (FA-2) and slumped (slumped FA-2) confined levees facies associations. Orange card is about 10 cm long. (A) F9b facies which is composed of centimetric-thick silty to very-fine-sand turbidites, and centimetric- to decimetric-thick fine-sand turbidites. This facies do not shows any internal structure. (B) Common F9a facies (F9a-5 facies) that exhibits decimeter-thick very-fine-sand turbidites with convolutes. (C) Less common F9a facies (F9a-6 facies) that shows low amplitude bed waves of unidirectional ripples that are always oriented toward the SSE. (D) Lenticular bodies of metric thickness and low lateral extension that are mainly filled by F8 facies which is made of decimetric- to multi-decimetric-thick and medium-sand beds. (E) Small-scale channel features which are here located at the base of shallow depressions that are controlled by small syn-sedimentary grabens. One of them shows cross-stratifications that characterize a lateral-accretion process. LAPS, lateral-accretion packages.</figcaption></figure>
<figure><img src="image_7.png" /><figcaption>**Fig. 5.** Two examples of slumped confined levees (slumped FA-2) observed within the Schistes Bruns Member. Bedding is illustrated with white dashes. (A) Slumped turbidites mainly composed of F9b facies that show decollement surfaces (purple dashes) separating levels that are more or less disturbed. (B) Slumped turbidites mainly composed of F9b facies that show bed disaggregation or duplex initiation (pink dashes), which lie above disturbed levels of marly mudstone (slumped FA-1, Fig. 3E). The last lie above undisturbed marly mudstones (F9a-1, Fig. 3A) that onlap against the Grès d'Annot Upper Erosion Surface (GAUES). Disturbed marly mudstone and the base of disturbed turbidites are composed of decollement surfaces (purple dashes).</figcaption></figure>

(Fig. 6, Table 1).

The first type (facies F0-1) consists of massive blocks of metric to multi-metric diameter. They often show a thickness greater than or equal to their width, which gives them a cubic or even trapezoidal shape. Their sides are cut sub-perpendicular to their internal stratification (Fig. 6A). They can show an exclusively brittle-type internal deformation when they consist of massive beds of Annot Sandstone (Fig. 6B). Their deformation is rather ductile or more fragile when they consist of

decimeter-thick beds of Annot Sandstone alternating with clayey levels (Fig. 6A and B). The Schistes Bruns packing the olistoliths are intensely deformed, and in some cases exhibit isoclinal folds (Fig. 6A). The blocks are always located within depressions and/or close to steep walls formed by the Grès d'Annot Upper Erosion Surface. They are interpreted as blocks of pre-existing Annot Sandstone that fell within the canyon during its formation/in-filling.

The second type (facies F0-2) is made of masses of Annot Sandstones,
<figure><img src="image_8.png" /><figcaption>**Fig. 6.** Olistolith facies association (FA-3) that consists of masses of Annot Sandstones remobilized and redeposited mostly within the Schistes Bruns Member. White dashes indicate the internal bedding of the blocks or of the Schistes Bruns, pink dashes indicate the internal shear surfaces within the blocks, purple dashes indicate the decollement levels at the base (or the border) of the blocks. (A) Massive and fallen blocks of metric to multi-metric diameter with a cubic or even trapezoidal shape, which are composed of decimeter-thick sandstone beds alternating with clayey levels. The Schistes Bruns that pack the olistoliths are intensely deformed. (B) Multi-metric block composed of massive sandstone beds, the last show brittle internal deformation. Modified after Mercier et al. (2024). (C) Multi-metric block composed of massive sandstone beds, the block has a stratiform shape and shows few internal deformation. ISaBES, Intra Schistes à Blocs Erosion Surface.</figcaption></figure>

whose sizes vary from multi-decimeter thick and 1-m long to multi-meter thick and multi-meter long. Their base is subparallel to the stratification of the Schistes Bruns Member. In contrast to the fallen blocks previously described, here the blocks have a more stratiform

appearance and show few internal deformation (Fig. 6C). They are generally isolated on flat surfaces of the Grès d'Annot Upper Erosion Surface corresponding to canyon terraces and therefore have smaller dimensions. More rarely, they can constitute a wide and thick mélange
with surrounding Schistes Bruns at the front of the massive mass-transport deposit "MTD4" mapped and described by Mercier et al. (2024) (see Figs. 2 and 8 for more details) on the canyon flank and thalweg. In this case, blocks are interpreted as outrunner blocks i.e. ejected blocks from the front of the MTD4 during its emplacement.

### 4.1.4. Olistostrome facies association

The F-Ex1 facies consists of rock clasts floating in a black marly matrix easily friable (Fig. 7A) and consisting of a microbreccia of shaly particles (Kerckhove, 1975). The size of the clasts increases towards the top of each bed. The clasts are centimetric to pluri-decimetric, their average size being a few decimeters (Fig. 7A). When this facies is found within the Schistes Bruns Member, clasts can be up to 1 m in diameter. Clasts are composed of 20 % of fragments of Helminthoid Flysch beds (Kerckhove, 1975). The latter have an angular or sub-angular shape, exhibit a yellow ochre weathering patina (Fig. 7A), and are often affected by calcite-mineralized fractures (Fig. 7E). Otherwise, clasts are derived from other series of allochthonous affinity such as Priabonian sandstones, or Upper Cretaceous globigerina calcoschists (Kerckhove, 1975). A few elements of blue-break mudstone, potentially of Middle Jurassic age, can also be identified.

F-Ex2 facies is a variant of F-Ex1 facies. It is only found interbedded within the Schistes Bruns Member, either in the form of beds rarely exceeding 1 m in thickness (Fig. 7B), or as metric lenses within F-Ex1 facies. The matrix is silty-clayey, with a yellow ochre alteration patina (Fig. 7C) and grey to dark in fresh breaks (Fig. 7B). The matrix may vary laterally into pockets of coarse sandstone (Fig. 7D). Matrix-supported clasts vary vertically in size from sands to multi-decimeter blocks toward the top of the layer. Most of the granule-, gravel-, and pebble-sized clasts consist of indurated silty-clay material (Fig. 7B, C, 7D). Most boulder-sized clasts are composed of angular to sub-angular pieces of Helminthoid Flysch beds (Fig. 7D). In addition, the remaining 10–20 % of the clasts are composed of 1) the same silty clays that make up the smaller particles (Fig. 7B and C), 2) a mudstone with a white weathering patina (Fig. 7C) similar to the Cretaceous calcschist olistoliths described by Kerckhove (1975) and redeposited within the Schistes à Blocs Exotiques Member, or 3) limestones with a blue patina (Fig. 7D) similar to Jurassic olistoliths redeposited within the Schistes à Blocs Exotiques Member.

F-Ex3 facies is similar to F-Ex1 facies, but blocks reach several meters in diameter at the top of the beds. The latter commonly consist of pieces of the Helminthoid Flysch series showing ductile deformation (Fig. 7E). This facies is only observable within the Schistes à Blocs Exotiques Member.

The previously described facies constitute only some intervals of the Schistes Bruns Member, while they compose the entire Schistes à Blocs Exotiques Member, in each case referring to facies association FA-Ex (Table 1). Within the Schistes à Blocs Exotiques Member, the bases of blocky layers are difficult to identify because they do not exhibit clear basal erosive surfaces. They can be roughly delineated based on the vertical evolution of the size of the clasts, and/or of the lithological composition of the latter (Fig. 7A and E). These three facies are interpreted as olistostromes, which is argued in section 5.1.

### 4.2. Polyphased architecture of the canyon-fill succession

The two members of the Schistes à Blocs Formation are separated by a surface named Intra Schistes à Blocs Erosion Surface (ISaBES). In the following paragraphs, we will use a representative example of both the overall architecture of the La Bonette Canyon and its infilling succession (Figs. 8–10). The typical cross-section profile of the La Bonette Canyon formed by the excavation of the Grès d'Annot Upper Erosion Surface consists of a canyon thalweg, corresponding to the deepest and central area of the La Bonette Canyon, surrounded by steep canyon flanks with staircase-like morphologies interpreted as terraces. This pre-existing morphology was then infilled by the Schistes Bruns and Schistes à

Blocs Exotiques members (Figs. 8 and 9).

This section aims: 1) to place the sedimentary facies and facies associations, which constitute both members, in their environmental context and 2) to analyze their spatial distribution within the canyon infilling. In addition, we describe the features of the internal surface that separates the two members, which allow us to clarify how the La Bonette Canyon evolved.

#### 4.2.1. Infilling of the canyon thalweg and local depocenters by the Schistes Bruns member

The canyon thalweg that commonly shows multi-decimeter- to hectometric-high lateral walls (Mercier et al., 2024, Figs. 9 and 10), is filled-up by fine-grained facies corresponding to in place and slumped confined levees (Schistes Bruns Member s.s.) and by olistolith breccia intervals composed of reworked Annot Sandstones (Figs. 8–10). At least three olistolith intervals are intercalated within the basal 50 m of the thalweg-fill succession, the thickest (second) one reaching 10 m in thickness (Sab27 section; Figs. 9 and 10). Two pluri-metric thick FA-Ex can also be found interbedded within the lower thalweg-fill succession (Fig. 10). The thalweg infilling overlies a 100 m-thick mass-transport deposit ("MTD1" of Mercier et al., 2024, Fig. 9).

Olistoliths are also filling-up local depressions that are perched above the canyon thalweg and located on the canyon flanks. The steep flanks of these depressions are controlled by syn-sedimentary normal faults, as it is for the Baisse de la Plate tributary that is located on the western crest of the Braissette valley (Mercier et al., 2024, Fig. 2).

#### 4.2.2. Facies and architecture of the Schistes Bruns member over canyon terraces

Several levels of canyon terraces were cut within the Grès d'Annot Formation by the emplacement of the Grès d'Annot Upper Erosion Surface (Figs. 8–10). The location of some terraces can fit with the emplacement of fault footwalls (Mercier et al., 2024) as for the faults F1b and F2 (Fig. 9) but not necessarily. In most locations, no lateral continuity exists between the Schistes Bruns Member covering terraces and the one infilling the thalweg as previously described. This is due both to the late activity of faults, and to the truncation of the Schistes Bruns Member by the ISaBES toward the south (Fig. 10). Nevertheless, a representative stratigraphic architecture of the Schistes Bruns Member covering three fault-controlled terraces and sealing the faults is illustrated by the correlation seen on the field at the Col du Colombart (Fig. 10).

The lower erosive terrace investigated (T1) is located below Sab28 section. It has a small lateral extension; it is bounded to the north by a wall about 10 m high, mainly covered in onlap by a FA-1 (Fig. 10). The latter overlies a breccia bed made of translated beds (i.e. FA-3) of Annot Sandstones to the north, and fallen metric blocks to the south. At the southern limit of the terrace, this entire marly-facies association is truncated towards the thalweg by a unit related to a slumped confined levee (FA-2; Fig. 10).

The second terrace investigated (T2) corresponds to the Sab29-30 sections (Fig. 10). It is bordered by a steep wall about 50-m high. A massive block of Annot Sandstones is tilted at the base of the wall, locally forming a local FA-3 (Fig. 10A and B). The wall is covered in onlap by the same FA-1 covering T2, and the latter is truncated by a slumped FA-1. Both the marly facies association FA-1 and slumped FA-1 are eroded and draped by a FA-Ex (Fig. 10). The latter is thicker along Sab28 section, where a multi-meter-thick olistostrome of F-Ex2 facies is intercalated between two F-Ex1 olistostromes, and it is thinner along Sab29 where the F-Ex2 facies is not present. The upper part of the wall and the FA-1 are cut and covered by a second unit of slumped confined levees (Fig. 10).

The third terrace investigated (T3) corresponds to the Sab31-32 sections (Fig. 10). By comparison with the previous ones, the basement of the terrace fitting with the GAUES constitutes a small depression 7–8 m deep (Fig. 10C). The lowest point of the depression is completely
<figure><img src="image_9.png" /></figure>

<figure><img src="image_10.png" /></figure>

<figure><img src="image_11.png" /></figure>

<figure><img src="image_12.png" /></figure>

<figure><img src="image_13.png" /></figure>

(caption on next page)
**Fig. 7.** Block-in-matrix which compose the Schistes à Blocs Exotiques Member and few levels within the Schistes Bruns Member. Orange card is about 10 cm long. (A) F-Ex1 facies which is composed of angular to sub-angular clasts floating in a black marly matrix. The size of the clasts increases towards the top of each bed, and are centimetric to pluri-decimetric fragments of sedimentary series of allochthonous affinity (80 %) and Helminthoid Flysch (20 %). Clasts often exhibit a yellow ochre weathering patina. (B) F-Ex2 facies that is a variant of F-Ex1 facies, and is only found interbedded within Schistes Bruns Member in the form of metric-thick beds or as metric lenses within F-Ex1 facies. The matrix is silty-clayey, and may vary laterally into pockets of coarse sandstone both containing very badly sorted clasts (granules, gravels, pebbles, boulders). (C) Close-up view of the F-Ex2 facies exhibiting a silty-clayey matrix. (D) Close-up view of the F-Ex2 facies exhibiting a sandy matrix. (E) Olistostrome facies association (FA-Ex) that constitutes the Schistes à Blocs Exotiques Member, and which is made of F-Ex1 and F-Ex3. F-Ex3 facies is similar to F-Ex1 facies but shows blocks which can reach several meters in diameter and which commonly consist of pieces of the Helminthoid Flysch series showing ductile deformation.

<figure><img src="image_14.png" /></figure>

**Fig. 8.** Outcrop of the western side of Tête du Clot des Pastres which is located in the western part of the study area (modified after Mercier et al., 2023; Mercier, 2022). See Fig. 2 for location. (A) Uninterpreted panorama, picture is taken by drone. (B) Interpreted panorama showing the deepening of the ISaBES within the canyon axis. The lower stratigraphic position of the ISaBES is limited to the top of MTD4 (mass-transport deposit). MTD4 structural domains are also illustrated. Summits indicated by the prefix (i) are located in the foreground, (ii) in the middleground and (iii) in the background. Abbreviations: A.I., axial incision; Au, Autapie nappe; BF, Bergère Fault; Br, Briançonnais tectonic slices; CB; Cime de la Bonette; CBF, Caire Brun Fault; CC, Col de Colombart; CF, Chevalier Fault; CP, Cime de la Plate; DKL1, Debrite Key Level 1; DKL2, Debrite Key Level 2; GAUES, Grès d'Annot Upper Erosion Surface; GF, Gendron Fault; h, height; JF, Joubarde Fault; MF, Musique Fault; SBUES, Schistes Bruns Upper Erosion Surface; SCB, Sommet de Caire Brun; SRKL3, Shale-rich Key Level 3; TC, Tête de Cristel; TCP, Tête du Clot des Pastres; TG, Tête de Glaudon; THF, Trois Hommes Fault; TL, Tête du Lau; TR, Tête Ronde; TS, Tête de Sanguinière; w, width; Wf, wildflysch.

infilled by a FA-1 (Sab32; Fig. 10). The latter begins with an intensely bioturbated interval of facies (F9a-4), and is locally punctuated at its base by a single slumped bed of Annot Sandstone (Fig. 10C). Above the infilling of this depression, the Schistes Bruns Member consists of marls or confined-levees facies with a moderate to high intensity of slumping depending on the layers considered, in a series that passes vertically

from a slumped FA-1 to a slumped FA-2. The base of the latter is defined by a slumped and metric-thick siltite lens of F9a-2 facies (Fig. 10C). The summit of the slumped FA-2 is truncated by a slump-like scar (Fig. 10A–C), which is covered by a pluri-metric thick slumped FA-1, interpreted to be the lateral variation of the upper slumped FA-2 covering the terraces T1 and T2. Finally, the upper-most slumped FA-
<figure><img src="image_15.png" /><figcaption>**Fig. 9.** Outcrop of the western side of Col du Colombart which is located in the eastern part of the study area. (modified after Mercier et al., 2023; Mercier, 2022). See Fig. 2 for location. (A) Uninterpreted panorama, picture is taken by drone. (B) Interpreted panorama showing the control of N80°E normal faults on the canyon cross-section profile. Within the canyon axis, the ISaBES completely cuts through the Schistes Bruns Member and is limited to the top of MTD1 (mass-transport deposit). Tectonic activity of faults F2 and F3 continues during and/or after the infilling of the canyon by Schistes à Blocs Formation as testifies the vertical offset of the. The transport directions of MTDs 1 and 2, their lateral walls and internal structural blocks are illustrated. Location of Fig. 10 and sections 27-32 are also indicated. Abbreviations: A.I., axial incision; Au, Autapie nappe; DKL1, Debrite Key Level 1; DKL2, Debrite Key Level 2; SB, Schistes Bruns Member.</figcaption></figure>

1 is truncated by an internal erosion surface draped by a few meters-thick FA-Ex (Fig. 10).

### 4.2.3. Properties of the ISaBES at the top of the Schistes Bruns member

Within the thalweg and on the terraces, the upper part of sediment infilling of the Schistes Bruns Member stops abruptly against the ISaBES i.e. Intra Schistes à Blocs Erosion Surface (Fig. 10). The map analysis (Fig. 2) of the ISaBES together with the interpretation of several cross-sections through the La Bonette Canyon (Figs. 8 and 9) reveal that the stratigraphic position of the surface is variable (Figs. 8–10). Along the La Bonette Canyon, the lowest points of the ISaBES are stratigraphically located a few meters or a few tens of meters above the lowest points of the Grès d'Annot Upper Erosion Surface (Fig. 8). At some places, they

can also be located below the Grès d'Annot Upper Erosion Surface (Figs. 9 and 10). These observations reveal i) the erosive character of this internal surface testifying of a sharp change in the infilling of the LBC, ii) a spatial change in the intensity of the erosion within the La Bonette Canyon (Fig. 9). The highest points of the ISaBES are stratigraphically located along the edges of the La Bonette Canyon, the highest one corresponding to the Tête de Sanguinière, where therefore the Schistes Bruns Member onlaps the Grès d'Annot Upper Erosion Surface (Figs. 2 and 9) about 700 m higher than it does within the canyon thalweg (Mercier et al., 2024). Along these canyon edges, the ISaBES can partially or completely truncate the Schistes Bruns Member that is therefore only few meters thick (Figs. 2 and 8).

Along the La Bonette Canyon, the ISaBES generally follows the
<figure><img src="image_16.png" /><figcaption>**Fig. 10.** (A) Stratigraphic correlation within the infilling of the La Bonette Canyon (from section Sab27 to section Sab32 and the La Bonette Tributary (section Sab 33). These outcrops are located in the eastern part of the study area, see Figs. 2 and 9 for location. Terraces T1-T3 and sampling locations of samples Bo32, Bo33, and Bo35 are also indicated on the sedimentary logs. (B) Close-up view of the ISaBES that cuts through disturbed internal levees (slumped FA-2) of the canyon. The close-up view is located on the hanging wall of F2. (C) Close-up view of the outcrop from section Sab28 to section Sab32 which are located on F2 hanging wall and on F1 footwall. Note that the olistolith (FA-3) that lies above the terrace T2 is a fallen block sourced from the wall that separates the terraces T2 and T3. For more information about facies and facies associations, please refer to the figure captions of Figs. 3–7 and to the text. The “s” abbreviation written before facies association nomenclature signifies “slumped”.</figcaption></figure>
deepening trends of the Grès d'Annot Upper Erosion Surface but does not exhibit a similar staircase morphology (Figs. 9 and 10). The exception to this is located above the 100 m-high canyon wall, controlled by the syn-sedimentary fault F1b (Mercier et al., 2024), where the ISaBES also shows a sharp morphology which reuses the canyon basal incision (Fig. 9). Therefore, the ISaBES tends to smooth the morphology previously created by the Grès d'Annot Upper Erosion Surface, excepted at specific locations where normal faults were active during the infilling of the La Bonette Canyon, particularly within the canyon thalweg (Figs. 9 and 10). Anyway, the depocenters of both the SB and Schistes à Blocs Exotiques Member are superimposed.

### 4.2.4. Facies and architecture of the Schistes à Blocs Exotiques Member

The ISaBES is covered by the F1-Ex1 and F1-Ex3 facies (Fig. 10), constituting the facies association FA-3 typical of the Schistes à Blocs Exotiques Member. It is difficult if not possible to establish, even locally, stratigraphic correlations within the Schistes à Blocs Exotiques Member because of the inexistence of clear internal stratigraphic surfaces, and of the poor quality of the outcrops due to the friability of the marly matrix of the olistostromes (Fig. 7). Few observations regarding block size can nevertheless be made within this member:

(i) regardless of location, a vertical increase in block size is clearly observed as previously reported (Kerckhove, 1975; Inglis et al., 1981; Jean, 1985), at least over a thickness of a few meters, constituting a vertical transition from a F1-Ex1 to a F1-Ex3 facies (Fig. 7E),

(ii) in the depocenters formed by the deepening of ISaBES, the largest blocks are rather located in the basal tens of meters of the Schistes

à Blocs Exotiques Member. They generally consist of olistoliths with at least a multi-decimeter length and a thickness of the order of 10 m (Fig. 9), or even kilometer-long masses, of Sub-Briançonnais affinity (i.e. Mesozoic limestones), like those confined on the hanging wall of the Bergère Fault within the Clapouse valley (Fig. 2).

### 4.3. Constraints on the source area of the Schistes Bruns member

To better constrain the source area of the Schistes Bruns Member, we describe below i) the paleocurrent measurements made within the La Bonette Canyon and then ii) the dating of detrital zircons done using the U/Pb thermochronology method.

#### 4.3.1. Paleocurrent measurements

The use of paleocurrents to reconstruct the main transport direction of particles and their potential source area was difficult to achieve within the Schistes Bruns Member due to a lack of sedimentary structures within this predominantly clayey series (Fig. 3). In addition, facies F9b that is the most common turbidite facies (Fig. 4A), rarely shows well-developed ripples at the top of fine-sand beds. Trustworthy measurements of current ripples were made more frequently on F9a facies, which is less abundant in the study area (Fig. 4C). Thus, only 21 measurements were made on current ripples (Fig. 11). They revealed two opposite directions along an N-S axis, with vectors oriented mostly to the S and SSW. The majority of the south-facing values (N140°E to N220°E) originate from the northern canyon-flank, and to a lesser extent from the Baisse de la Plate tributary (Figs. 2 and 11). The value oriented N45°E also comes from the northern canyon-flank. The two north-facing values

<figure><img src="image_17.png" /><figcaption>**Fig. 11.** Paleocurrents (n = 21) measured on unidirectional ripples and low amplitude bed waves of unidirectional ripples which are interbedded within the Schistes à Blocs Member that fills the La Bonette Canyon and the Baisse de la Plate Tributary.</figcaption></figure>
(N345°E) were measured on the southern canyon-flank along the Col du Colombart cross-section (Fig. 9).

These paleocurrent directions are surprising given the east-west trend of the La Bonette Canyon. A reasonable interpretation would suggest the recording of lateral sediment input coming from the canyon flanks in the form of low-density turbulent flows. This will be discussed in more detail in section 5.3.

### 4.3.2. Detrital zircon geochronology

Published zircon ages from Chu et al. (2016) come from the Schistes à Blocs Exotiques Member located near the Pelvoux Massif (sample ALP4-2, Fig. 12A). The ages range from 136 to 935 Ma. Three age peaks at 284 Ma, 449 Ma, and 585 Ma are dominant, although Triassic grains have been measured (Chu et al., 2016, Fig. 12A).

Our sample Bo33 comes from a siltstone bed located in section Sab32 (Fig. 10). The zircon ages vary mainly in two continuous groups of values between 240-380 Ma and 420-680 Ma, respectively. Three age groups at 280-310 Ma, 420-460 Ma and 520-600 Ma are dominant within the spectrum, and a few Triassic as well as Cryogenian zircons were measured (Fig. 12B).

Sample Bo32 is from a coarse sandstone bed collected along section

Sab31 (Fig. 10). Zircon ages vary primarily in two continuous groups of values, between 270-320 Ma and 420-620 Ma, respectively. Three age groups at 270-320 Ma, 420-460 Ma, and 520-610 Ma are dominant within the spectrum, and a few Triassic and Cryogenian zircons were measured (Fig. 12C).

Sample Bo35 is from an isolated medium-grained sandstone bed of facies F8 collected along section Sab32 (Fig. 10). Zircon ages vary primarily in two continuous groups of values, between 280 and 460 Ma and 530 and 620 Ma, respectively. Three age groups at 280-310 Ma, 420-460 Ma, and 530-620 Ma are dominant within the spectrum, and a few Triassic and Cryogenian zircons were measured (Fig. 12D).

Sample Bo28b comes from a coarse sandstone bed collected in the Annot Sandstones Formation outcropping along the Bonette-Restefond road, in the Clapouse valley (Fig. 2). The zircon ages are discontinuous, as three dominant groups within the spectrum, at 280-320 Ma, 410-460 Ma and 530-640 Ma (Fig. 12E).

These results will be discussed below but they mostly exhibit three age peaks that fit with previous orogenies i.e. tardi-variscan (Permo-Carboniferous), Lower Paleozoic (Ordovician-Silurian) and Cadomian (Ediacaran), as recorded in all the western european cristalline massifs, and thus do not show any evidence of internal alpine sourcing.

<figure><img src="image_18.png" /><figcaption>**Fig. 12.** (A) Age diagram obtained by thermochronological analysis (U-Pb) on detrital zircons sampled in the Schistes à Blocs Exotiques (after Chu et al., 2016). (B-E) Age diagrams obtained by thermochronological analysis (U-Pb) on detrital zircons sampled in the Schistes Bruns Member and in the Annot Sandstones Formation (this study).</figcaption></figure>
# 5. Discussion

The following discussion stresses that the infilling of the La Bonette Canyon is an important feature that helps both to reconstitute the evolution of the inner part of the Western Alpine Foreland Basin during the Lower Oligocene, but also to understand the stratigraphic architecture of mud-prone seals in deep-water environments. Firstly, we identify both the sedimentary and external processes responsible for the singular stratigraphic architecture of the canyon-fill that is characterized by both periods of mud-prone deposition and erosion. In a second part, we identify the source of detrital inputs by using the results of the thermo-chronological analyses made on the detrital zircons sampled within the canyon-fill. Then, we propose five hypotheses about the possible pathways used by paleocurrents within the foreland basin, and we identify the one that best fits with our observations and the regional settings. Finally, we summarize the properties of this feature and why it constitutes a world-class analog of mud-prone stratigraphic seal.

## 5.1. Mud-prone infilling of a submarine canyon and origin of erosional surfaces

### 5.1.1. Mud-prone architecture of the submarine canyon-fill

Two different sets of facies associations can be discriminated within the infilling of the La Bonette Canyon, depending on their location in relation to the axis of the canyon thalweg and depending on their relative ages.

The canyon axis exhibits the greatest diversity of facies, which belong to the Schistes Bruns Member (Fig. 10). The most abundant facies consist of sandy to fine-grained turbidites building poorly-sandy internal levees (Fig. 4A). Within the latter, small sandy lenticular bodies are occasionally found and interpreted as short-lived channelizing features (Fig. 4D and E). Internal levees are most often slumped (Fig. 5) and show lateral variation of facies with increasingly clayey deposits interpreted as distal levees, the latter commonly onlapping southward and northward against the canyon flanks (Figs. 1, 8, 9, 10, 13A). Turbidite-prone accumulations are punctuated and deformed by the emplacement of olistoliths (Fig. 6A, B, 13A) or stratiform slides (Fig. 6C) and slumped levees sourced from the stepped canyon flanks (Fig. 10). Olistoliths are particularly abundant within the lower part of the canyon-fill (Fig. 10), but also within tributaries exhibiting steep lateral sides (Fig. 13A). Their presence could be the result of multiple factors: 1) the steep morphology of the canyon incision, 2) a relatively continuous fault control, particularly of the canyon thalweg. Moreover, some olistostromes are interbedded within thin-bedded turbidites filling the canyon axis (Fig. 10). They exhibit Helminthoid-Flysch clasts (Fig. 7B, C, 7D) that testify of the preferred pathway played by the canyon regarding olistostrome transport, which should result from the repetitive submarine destabilization of the nappe front (Kerckhove, 1969; Perotti et al., 2012).

Outside of the canyon axis and within higher stratigraphic levels, the Schistes Bruns Member exhibits its common characteristics with a strong predominance of marly facies (Figs. 10 and 13A) with a low sedimentation rate as evidenced by the preservation of condensed levels within hanging depressions (Figs. 3C-D and 10). Sand-rich series of turbidites are only rarely identified at the base of local depressions (Fig. 4E).

The mud-rich nature of the Schistes Bruns Member, as well as the condensed levels we locally observed at their base (Fig. 3C and D), and the rockfalls from canyon walls (Fig. 6A and 10), testify of a low sedimentation rate during the deposition of this lower member. The latter should result from: 1) the starvation of the La Bonette Canyon or 2) the deposition on the canyon flanks of fine-grained deposits in the form of internal levees, while the absence of coarse-grained particles within the thalweg would suggest their by-pass due to their transport by the dense part of the gravity flows and to their deposition further downstream in the sedimentary system.

Then, the ISaBES commonly truncates the Schistes Bruns Member with a higher erosive intensity following the canyon axis than close to its

lateral edges (Figs. 1, 8, 9, 10, 13B), which did not allow us to establish with certainty the complete upper evolution of the Schistes Bruns Member within the La Bonette Canyon. Above the ISaBES, the infilling architecture belonging to the Schistes à Blocs Exotiques Member become more monotonous with the omnipresence of thick and amalgamated layers of exotic clasts floating in a muddy matrix (Fig. 7E).

So a clear change in the style of the La Bonette Canyon infilling can be seen from either side of the ISaBES and may suggest:

1) below the ISaBES, a concentration of various types of gravity processes trapped within the canyon axis. Lateral facies variations range from internal levees with small channelizing structures to mud-prone distal levees (Fig. 13A), both recording the recurrent deposition by a large number of turbidity currents with various densities, and also to locally focused or more continuous olistoliths and olistostromes, recording the rarer but thicker deposition by mass wasting respectively providing from the canyon flanks or from the nappe front (Fig. 13A). At the opposite, interfluves and tributaries are mainly covered by distal-levee-like deposits dominated by decantation of silty clays (Fig. 13A),

2) above the ISaBES, the activity of turbidity currents and the sandy-terrigeous inputs stopped in favor of thick olistostrome events (Fig. 13B), which are by definition mass-transport deposits sourced from allochtonous units and promoted by the tectonic emplacement of these units (Festa et al., 2015; Kerckhove, 1969, 1975; Perotti et al., 2012; Pini et al., 2012).

Although the abrupt change in the style of infilling architecture and deposits cannot be explained with certainty, some hypotheses can be made. Because of the general westward migration of the nappe front during the Lower Oligocene (Dumont et al., 2022; Trullenque et al., 2006), the decreasing distance between the latter and the canyon head would gradually reduce. Therefore, it would suggest a change of the distance of the source of particles, i.e. the Alpine nappes, to the canyon head. This would promote more voluminous and/or frequent olistostromes that constitute the Schistes à Blocs Exotiques Member, than the gravity flows sourced from the Corsica-Sardinia and Maures-Estérels massifs and responsible for the deposition of the internal levees (i.e. Schistes Bruns Member). A third hypothesis is more theoretical: it considers the complete disconnection of the canyon head from the sedimentary inputs by two ways: 1) its plugging by the olistostromes, or 2) a change of the gravity flow pathway resulting from a tectonic uplift occurring upslope, close to the canyon head location.

### 5.1.2. Origin of the internal erosion surface

We discussed above of the sedimentary processes leading to the deposition of the mud-prone canyon-fill, which is constituted by two distinct sedimentary series i.e. the Schistes Bruns Member and the Schistes à Blocs Exotiques Member. Nevertheless, these two members are stratigraphically separated by an erosive surface i.e. the ISaBES. The presence of at least one strong erosive surface, the ISaBES, within this mud-prone infilling sounds like an antagonism. We propose below three hypotheses to explain the formation of this internal erosion surface.

Firstly, it is useful to remind the origin of the La Bonette Canyon which cuts through of the Annot Sandstones Formation. These turbidite lobes were previously deposited in a base-of-slope setting (Joseph and Lomas, 2004; Ravenne et al., 1987), or a distal confined basin (Butler et al., 2020). Thus, their erosion by a submarine canyon is suggested to be mainly due to a first phase of retrogressive erosion triggered by the modification of the slope of the Sanguinière-Restefond Sub-Basin due to tectonic activity, and potentially to the superimposition of the *Oila* eustatic fall (Mercier et al., 2024). These authors also proposed that 100 m-thick and 1 km-long MTDs affecting the southern canyon flank during the deposition of the Schistes Bruns Member, were triggered by the on-going activity of the rollover deformation controlling the canyon orientation (Figs. 2 and 13).
<figure><img src="image_19.png" /><figcaption>**Fig. 13.** Schematic diagram blocks showing the evolution of the infilling of the La Bonette Canyon, modified after Mercier et al., 2023; Mercier 2022. (A) First phase of infilling by the internal levees of the Schistes Bruns Member. (B) Second phase of cut-and-fill by the olistostromes of the Schistes à Blocs Exotiques Member. A similar evolution is proposed for the erosive features in the Lauzanier Sub-basin which are less constrained and interpreted from 2D outcrop data (Mulder et al., 2010). Abbreviations: BF, Bergère Fault; THF, Trois Hommes Fault.</figcaption></figure>
This leads to the first hypothesis of the ISABES formation, that considers a cut-and-fill sequence promoted by tectonic activity that occurred after the filling of the La Bonette Canyon below the Schistes Bruns Member. This first hypothesis is based on the observation that all the Schistes à Blocs Formation exhibits the same age, i.e. NP 22-23 (Mercier et al., 2024). It is thus impossible to date with precision the formation of the ISABES and so to associate with certainty its creation to a sea-level fall as it could be done for modern or ancient submarine canyons (Antobreh and Krastel, 2006; Baztan et al., 2005; Gong et al., 2011; Gorini et al., 2014). Therefore, the active tectonic deformation within the Sanguinière-Restefond Sub-Basin would have caused the regional slope angle to increase again after deposition of the Schistes Bruns Member, which in turn would have promoted another phase of retrogressive erosion affecting this time the Schistes Bruns Member. This tectonic deformation could have also affected the Autapie nappe during its submarine emplacement in the foreland, promoting mass wastings at the nappe front. Therefore, tectonic activity could have contributed to a rapid increase of the olistostrome events within the La Bonette Canyon and favored the burial of the ISABES below the Schistes à Blocs Exotiques Member.

The second and the third hypotheses consider the erosion capacity of the olistostromes which constitute the Schistes à Blocs Exotiques Member, because such deposits are described in other foreland basins as block-in-matrix deposits that unconformly lie above slope or base-of-slope deposits (Festa et al., 2015, 2016, 2019; Pini et al., 2012). Their erosion capability is caused by a flow transformation that occurs after a break-of-slope (Festa et al., 2016), and such flows have the capability to integrate substratum fragments of various sizes during their longitudinal displacement (Ogata et al., 2019). Nevertheless, the erosive features at the base of olistostromes are tens to hundreds of meters wide (Festa et al., 2016; Marini et al., 2022; Pini et al., 2012), but do not show any prominent and V-shaped erosion surface as exhibited by the ISABES (Figs. 9 and 10). It means that olistostromes are not able to form such an internal erosion surface during a single event. Thus, if we consider the ISABES was formed by the transport of olistostromes, this surface was formed diachronously in the form of a longitudinal/lateral amalgamation of erosion surfaces produced by the passage of several olistostromes that reused a previously existing morphology. Following these two hypotheses, the ISABES would be older within the thalweg part of the La Bonette Canyon and younger going upward on the canyon flanks.

Therefore, the second hypothesis considers that this pre-existing morphology results from an incision phase as proposed in the first hypothesis, i.e. due to retrogressive erosion occurring during phase of tectonic activity. Thus, successive olistostromes affected the internal erosion surface, but the first events affected mostly the thalweg while the following ones eroded mainly the canyon flanks during the aggradation of the deposits.

Finally, the third hypothesis considers that the ISABES mainly results from a depositional morphology, i.e. from the shape of the internal levels deposited on the canyon flanks, while the thalweg of the La Bonette Canyon acted as a by-pass conduit, as proposed in section 5.1.1, where few or no deposition occurred. Thus, the depositional morphology was modified diachronously from the bottom to the top, by the successive erosion-deposition phases related to the passage of successive olistostromes. Because we never observed any channelized and coarse-grained features preserved within the thalweg of the La Bonette Canyon, we propose that the third hypothesis would be the most probable.

## 5.2. Signature of terrigenous inputs

The detrital zircons analyzed within turbidites that were emplaced within the Schistes Bruns Member show the same three U/Pb age peaks as those analyzed in the Grès d'Annot Formation, dated to 280-340 Ma, 430-490 Ma and 540-610 Ma (Fig. 12). They respectively correspond to the tardi-variscan (Permo-Carboniferous), Lower Paleozoic (Ordovician-Silurian) and Cadomian (Ediacaran) events that are documented in the

Varisco massifs that have not undergone alpine metamorphism. In Corsica and Sardinia, large numbers of granite plutons were emplaced during the Carboniferous and Permian periods, in four events dated at ~350 Ma, 345-335 Ma, 305-290 Ma, and ~280 Ma (Cocherie et al., 2005; Li et al., 2014; Paquette et al., 2003; Rossi et al., 2006). In addition, the formation of tardi-variscan plutons of the Maures-Esterel massif is dated to ~290 Ma (Onézime et al., 1999). Finally, the two age groups of the metasedimentary rocks of Sardinia are dated to 450-480 Ma and 550-650 Ma respectively (Giacomini et al., 2006).

The U/Pb age obtained for the Annot Sandstones sample Bo28b (Fig. 12E) is consistent with the ages of pluton emplacement and metamorphism recorded in Corsica, Sardinia and in the Maures-Esterel. Moreover, the system of the Quatre-Cantons - Sanguinière-Restefond was fed by the erosion of the Corso-Sardinian and Maures-Esterel massifs (Jean et al., 1985; Joseph and Ravenne, 2001, Fig. 1A). Zircons within the Schistes Bruns Member exhibit the same ages (Fig. 12B-E) and would therefore result from the erosion of the same massifs.

The Schistes Bruns Member does not contain zircons which record the peak of western alpine metamorphism dated to 35-30 Ma (Ford et al., 2006; Hurford et al., 1991; Malusà et al., 2005). It is consistent with the obstruction of internal inputs coming from the erosion of High Pressure-Low Temperature internal units during both the Eocene and the Rupelian, due to the existence of the Briançonnais relief (Chu et al., 2016; Morag et al., 2008; Perotti et al., 2012).

Consequently, because the Schistes Bruns Member and the Annot Sandstone Formation cannot be differentiated in terms of sourcing, we interpret the Schistes Bruns Member as the continuation of the deposition of the Annot Sandstone turbidite system during NP22-23.

## 5.3. Paleocurrents within the internal foreland basin during the Rupelian

The paleocurrents measured within the Schistes Bruns Member mainly indicate a main S or SSW direction of transport (Fig. 11), revealing a strong change with the NW paleocurrents measured in the Annot Sandstones Formation located within the Sanguinière-Restefond Sub-Basin (Jean et al., 1985). We propose below several hypotheses explaining this change: hypothesis 1) and 2) imply a change in the sedimentary source, whereas the three other implies a conservation of the existing sources, but a partial or complete modification of the transport pathway of particles.

### 5.3.1. First routing hypothesis

A change of the supply source between the end of deposition of the Annot Sandstones Formation and the formation of the La Bonette Canyon then its infilling implies the outcropping of a “new” crystalline bedrock located to the north. This first hypothesis should be rejected for several reasons: 1) the Annot Sandstones Formation and the Schistes Bruns Member exhibit the same detrital zircon signature (Figs. 12), 2) the regional slope dipped in theory westward or northwestward (Mercier et al., 2024), instead suggesting a source-rock in the opposite direction, 3) the Pelvoux massif is located north to the study area (Fig. 1) and exhibits the same signature than the Corsica/Sardinia/Maures-Esterel massifs (i.e. western European basement). Nevertheless, studies made in the Pelvoux area did not reveal any proof of emersion of such a crystalline massif during the Rupelian (Butler et al., 2020; Vinnels et al., 2010a).

### 5.3.2. Second routing hypothesis

The basal infilling of the La Bonette Canyon corresponding to the Schistes Bruns Member was not directly fed by the fan-deltas that were active during the deposition of the Annot Sandstones Formation, but was mainly sourced by the submarine reworking by slope failures of the Annot Sandstones Formation that covered the northern part of the foreland basin, such as the Eastern Champsaur Sub-Basin (Fig. 1A). This second hypothesis is plausible as the Eastern Champsaur Sub-Basin shows a significant tectonic activity during the emplacement of the
Frontal Pennine Thrust at ca 33 ± 0,6 Ma (Jourdan et al., 2013), i.e. during NP22 (and possibly also NP21 or also NP23; Fig. 1B). This tectonic activity continued after the nappe emplacement (Dumont et al., 2011, 2012), so at the end and after the deposition of the Annot Sandstones within the Eastern Champsaur Sub-Basin (Butler et al., 2020), i.e. before and during the deposition of the Schistes à Blocs Formation. Thus, this enhanced tectonic activity is a good candidate for both: 1) the generation of a southward dipping slope that would bound the northern part of the foreland during the deposition of the Schistes à Blocs Formation, and 2) the triggering factor of repetitive submarine landslides affecting the Annot Sandstones Formation, which were remobilized along this slope, and finally redeposited in the form of confined levees within the La Bonette Canyon.

### 5.3.3. Third routing hypothesis

During NP22-23, a complex pathway implying a northward transport of terrigenous particles through neighbouring sub-basins (i.e. Lauzanier and Trois Evêchés, Fig. 1A) and even epi-nappe basins (i.e. basins transported on the Autapie nappe-back) would have allowed submarine currents to flow northward (within one of these sub-basins) and then to be reoriented southward before their entrance within the Sanguinière-Restefond Sub-Basin. Such a configuration is possible in a submarine fold-and-thrust belt that can lead to multiple and complex flow pathways (Bourget et al., 2011) and to deposition within ponded basins (Bourget et al., 2011; Morley and Leong, 2008; Naranjo-Vesga et al., 2020; Ratzov et al., 2012; Vinnels et al., 2010b). Presently, the third hypothesis cannot be established robustly due to the lack of paleocurrent-related features within the Schistes Bruns Member outcropping within the sub-basins of the Lauzanier, Trois Evêchés and Eastern Champsaur (Fig. 1).

### 5.3.4. Fourth routing hypothesis

The fourth hypothesis implies a rebound and a dispersion of submarine currents against the northern flank of the La Bonette Canyon which is particularly steep (Mercier et al., 2024). Canyons which cut continental shelves can intercept coastal drift currents and pirate a part of their particle load which can then flow within the thalwegs in the form of turbulent flows, such as it is the case for the modern Zaire Canyon (Babonneau et al., 2002) and the Capbreton Canyon (Mazières et al., 2014). The two NNW paleocurrent measurements recorded on the southern canyon-flank (Fig. 11) could evidence a similar process of piracy, the canyon being oriented sub-perpendicular to the NW-dipping slope of the Sanguinière-Restefond Sub-Basin, because of its deeper northern interfluve (Mercier et al., 2024, Figs. 2 and 13).

Moreover, rebound and dispersion of current directions are also common in channelized structures such as canyons and sinuous turbidite channels (Peakall et al., 2000; Taylor et al., 2024; Wynn et al., 2007). A similar process was interpreted within proximal internal levees of an outcropping channel, where low amplitude bed waves of unidirectional ripples are preserved, and are interpreted as the result of flow reflection against a containing slope (Taylor et al., 2024). It was also observed in ponded basins (Tinterri et al., 2022). We observed similar sedimentary structures within the proximal internal levees of the La Bonette Canyon that mainly records paleocurrents oriented towards the SSW (Figs. 4C and 11). Such phenomena could be favored by the asymmetrical cross-section profile of the canyon and its particularly steep northern flank (Mercier et al., 2024, Fig. 10). The overall morphology of the La Bonette Canyon could also promote the lateral capture of currents sourced from the south or the SE (Fig. 11).

Finally, the channel architecture described by Taylor et al. (2024) teaches us that such sedimentary structures can be generated by overbank processes initiated from gravity currents that are axially transported within the canyon or the channel. In the aim to better reconstitute the role of the La Bonette Canyon within the Western Alpine Foreland Basin during the Lower Oligocene, we have also to consider the role and the characteristics of the submarine canyons which cut though

modern accretionary prisms. Canyons constitute important or even indispensable features for the transport of particles from the shelf to the active trench, although the pathway is segmented in depositional areas located within perched and intermediate piggy-back basins (Bourget et al., 2011; Morley and Leong, 2008; Naranjo-Vesga et al., 2020; Ratzov et al., 2012; Vinnels et al., 2010b). This connectivity function is also assumed for submarine canyons exhibiting modest dimensions such as those of the Sinù accretionary prism (Naranjo-Vesga et al., 2020). So, it is more reasonable to suppose that the La Bonette Canyon was more developed than its preserved pathway suggests (Mercier et al., 2024, Figs. 1 and 2), and thus probably exhibited its trunk or a tributary connected to an up-dip source, which was located southward (Fig. 13A). This assumption is particularly pertinent if the La Bonette Canyon thalweg was dominated by by-pass processes as we suggested in section 5.1.1, meaning that high energy and sustained gravity flows had to use it, the flows necessarily originating from a permanent source located southward and connected to the La Bonette Canyon. This hypothesis is therefore highly relevant.

### 5.3.5. Fifth routing hypothesis

The fifth hypothesis is the basin-scale rebound of submarine currents against the northern basin border, as it is observed for mud-prone turbidites in analog slope-confined basins (Siwek et al., 2023). Nevertheless, we could probably discard this hypothesis because the La Bonette Canyon would have acted as a trap, or as a preferential conduit, for particles during their northwestward transport, and thus would not have allowed currents to flow so far northward to experience a distal rebound.

## 5.4. Reservoir analog and seal properties

Nowadays, many onshore and shallow offshore hydrocarbon fields are relatively mature. In these mature provinces, the structural traps that were historically the main targets are now giving way to stratigraphic traps as the only potential targets for oil exploration (Allen et al., 2006). In these areas, most traps have a purely stratigraphic or combined stratigraphic-structural component. A better understanding and prediction of the trapping types is therefore a real industrial challenge, despite the contribution made by 3D seismic data. Stratigraphic traps can take many geometries. In several cases, they involve a truncation of the reservoir that is then covered by impermeable deposits (Allan et al., 2006; Amy, 2019; Dolson et al., 2017). This is the case for reservoirs incised by clay-filled submarine canyons which are commonly known as buried-hills (Allan et al., 2006; Dolson et al., 2017).

Clay-infilled canyons truncate reservoirs that may consist of deltaic deposits (Clayton and Olariu, 2022; Cornish, 2013; Cornish and Lambiotte, 2016; Doust and Omatsola, 1990; Galloway et al., 1991; McGee et al., 2017; Mercier et al., 2023; Weimer and Link, 1991), tidal deposits (Matesic, 2012) or deep turbidite deposits (Dailly et al., 2002; Jean et al., 1985; Mercier et al., 2024). A canyon can then generate major incisions in the underlying series (up to 1.6 km deep) and cannibalize the continental shelf and earlier deposits by successive retrogressive erosions (Chen et al., 2024; Galloway et al., 1991; Mercier et al., 2023; Tournadour et al., 2017; Weimer and Link, 1991). The sheer size of some fossil clay-infilled canyons makes them an ideal trapping site for regional exploration. Studying them and understanding the system to which they belong therefore increases the potential for discoveries in a given area.

As we described and discussed in the previous sections, the infilling of the La Bonette Canyon is mainly made of deep-water deposits presenting a poor sand/mud ratio, such as silty hemipelagites and turbidites (Fig. 3A and B), fine- to very- fine-grained turbidites (Fig. 4A, B, 4C), slumped hemipelagites/turbidites (Fig. 5), and matrix-supported debrites (Fig. 6), whereas sand-prone channelizing structures are uncommon and poorly developed in terms of thickness and lateral extension (Fig. 4D and E). Moreover, the La Bonette Canyon cuts through the sand-rich Annot Sandstones Formation (Jean et al., 1985; Mercier et al.,
2024). Thus, the La Bonette Canyon is quite singular because most of present-day or ancient submarine canyons, whatever they incise a passive or active/transform margin, 1) cut through a muddy continental slope, and 2) are filled with coarse sediment which are sand- or even gravel-rich confined turbidite channels and levees (Babonneau et al., 2002; Bouwmeester et al., 2025; Bozetti et al., 2023; Cronin et al., 2007; Deptuck et al., 2007; Di Celma, 2011; Di Celma et al., 2014; Hsieh et al., 2020; Zecchin et al., 2011).

Within the La Bonette Canyon, the Schistes Bruns Member is 80-90 % clayey as we described in section 4.1.1 (Figs. 3-7, 10) due to the over-representation of mud-prone internal levees within the basal canyon-fill. They are abundantly slumped (Figs. 1, 5 and 10, 13A) and greatly accentuate the impermeability of the canyon-fill. Thus, the Schistes Bruns Member probably provides a field analog of the mud-prone fillings sealing reservoirs truncated by submarine canyons resulting from tectonic inversion as it is the case for 1) turbidite deposits of the Ceiba field in Rio-Muni (Daily et al., 2002), or 2) shelf deposits of the Gorae and Dolgorae fields in South Korea (Park et al., 2019).

Moreover, the strong truncation of the Schistes Bruns Member by the ISaBES, occurring both within the canyon axis and on the canyon flanks (Figs. 8–10), and its burying below the olistostromes of the Schistes à Blocs Exotiques Member (Figs. 10 and 13B), allow us to qualify the canyon-fill as high-quality seal.

## 6. Conclusions

Through combined sedimentological, stratigraphical and geochronological analyses of outcrops belonging to the Sanguinière-Restefond Sub-Basin, we reconstructed the Rupelian evolution history of the La Bonette submarine canyon, located in the internal part of the Western Alpine Foreland Basin. The canyon cuts 700 m deep within the Annot Sandstones Formation and it is filled-up by the mud-prone Schistes à Blocs Formation, which occurred during the activity of the Colombart Structure. The stratigraphy of the canyon-fill was reconstructed using sedimentary logs, GIS mapping and drone acquisition. We provide for the first time a depositional model for the Schistes Bruns Member which constitutes the lower unit of the Schistes à Blocs Formation. We also reconstructed the stratigraphic architecture of the canyon-fill, which implied to study the link existing between the stratigraphy of the canyon-fill (i.e. Schistes Bruns et Schistes à Blocs Exotiques members) and the canyon morphology.

The Schistes Bruns Member recorded paleocurrents in the form of unidirectional ripples and low amplitude bed waves of unidirectional ripples, which are all oriented perpendicularly to the canyon axis. Unidirectional ripples observed within low amplitude bed waves are oriented toward the thalweg, which is coherent with both: 1) turbulent flow rebound against the steep northern flank of the canyon and, 2) a similar process observed in another field analogue described in the literature (Taylor et al., 2024). Moreover, the grain-size of turbidites decreases from the canyon axis to the external borders of internal levees. The Schistes Bruns Member results from the construction of internal and external levees, while the thalweg of the canyon was dominated by by-pass processes. Moreover, frequent canyon-wall and levee collapses occurred during the deposition of this lower unit, favouring its stratigraphic complexity and thus improving its seal properties. The thermochronological analysis of detrital zircons sampled within turbidites reveals that the Schistes Bruns Member is sourced by the same sedimentary system than which of the Annot Sandstones Formation. Thus, we interpret both canyon formation and the by-pass occurring within its thalweg as the consequence of the basin slope increase, due to the tectonic activity that operated during the propagation of the accretionary prism. Thus, the La Bonette Canyon was an important feature of the Western Alpine Foreland Basin during the Rupelian, by connecting the up-slope sub-basins to the active trench. The Internal Schistes à Blocs Erosion Surface that deeply cuts within the lower unit of the canyon-fill is a composite and diachronous surface. The latter is the result of both:

1) the morphology of the thalweg-facing edges of the constructive internal levees of the canyon, and 2) the partial reworking of this morphology by the bases and the borders of the amalgamated and erosive olistostromes that constitute the Schistes à Blocs Exotiques Member. We suppose that the latter were sourced from the East, which potentially implies the connection between the Sanguinière-Restefond Sub-Basin and the more internal sub-basins during the late infilling of the canyon.

Consequently, we provide an integrated picture of a canyon development in a convergent setting and thus demonstrate why this kind of geological feature helps to reconstruct the paleogeographic evolution of a foreland basin, but also why it constitutes an excellent analogue of seal for oil and gas reservoirs that are commonly truncated in such tectono-sedimentary context.

## CRediT authorship contribution statement

**Louison Mercier:** Writing – review & editing, Writing – original draft, Validation, Supervision, Project administration, Methodology, Investigation, Conceptualization. **Sébastien Migeon:** Writing – review & editing, Supervision, Resources, Project administration, Investigation, Funding acquisition, Conceptualization. **Jean-Loup Rubino:** Resources, Project administration, Funding acquisition, Conceptualization. **Yamirka Rojas-Agramonte:** Writing – review & editing, Writing – original draft, Methodology, Formal analysis. **Anna Hagen:** Writing – review & editing, Formal analysis, Data curation. **Romain Bousquet:** Formal analysis, Data curation. **Regina Mertz-Kraus:** Writing – review & editing.

## Declaration of competing interest

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Louison Mercier reports financial support was provided by Total-Energies SE. Louison Mercier reports financial support was provided by ANRT. Louison Mercier reports financial support was provided by ARMINES. Louison Mercier reports financial support was provided by CNRS. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

## Acknowledgments

Louison Mercier's PhD has been funded by TotalEnergies and the ANRT, and the redaction of this work was done thanks to the financial support of UMR Géoazur (CNRS) and ARMINES. The authors are grateful to the Parc National du Mercantour for giving permission to realize sampling and drone acquiring. Finally, the authors sincerely thank Dr. Marco Patacci and two anonymous reviewers for their helpful remarks that greatly improved this article.

## Appendix A. Supplementary data

Supplementary data to this article can be found online at https://doi.org/10.1016/j.marpetgeo.2025.107620.

## Data availability

Data will be made available on request.

## References

Allan, J.R., Sun, S.Q., Trice, R., 2006. The deliberate search for the stratigraphic and subtle combination traps: where are we now? In: Goffrey, G.P., Morgan, R.K., Walker, I.M. (Eds.), The Deliberate Search for the Stratigraphic Trap. Geological Society London Special Publications. M.R. Allen, pp. 56–103. https://doi.org/10.1144/GSL.SP.2006.254.01.05.
Allen, M.R., Goffrey, G.P., Morgan, R.K., Walker, I.M., 2006. The deliberate search for the stratigraphic trap: an introduction. In: Allen, M.R., Goffrey, G.P., Morgan, R.K., Walker, I.M. (Eds.), The Deliberate Search for the Stratigraphic Trap, Geological Society London Special Publication, pp. 1–5. https://doi.org/10.1144/GSL.SP.2006.254.01.01.

Amy, L.A., 2019. A review of producing fields inferred to have upslope stratigraphically trapped turbidite reservoirs: trapping styles (pure and combined), pinch-out formation, and depositional setting. AAPG (Am. Assoc. Pet. Geol.) Bull. 103, 2861–2889. https://doi.org/10.1306/02251917408.

Antobreh, A.A., Krastel, S., 2006. Morphology, seismic characteristics and development of Cap Timiris Canyon, offshore Mauritania: a newly discovered canyon preserved-off a major arid climatic region. Mar. Petrol. Geol. 23, 37–59. https://doi.org/10.1016/j.marpetgeo.2005.06.003.

Apps, G., 1985. The Grès d'Annot foreland basin, Haute Provence: the control of turbidite deposition by structurally induced basin floor topography. Presented at the 6th European Regional Meeting of Sedimentology IAS Lleida, pp. 18–21.

Apps, G., Peel, F., Elliott, T., 2004. The structural setting and paleogeographical evolution of the Grès d'Annot Basin. In: Joseph, P., Lomas, A. (Eds.), Deep-Water Sedimentation in the Alpine Foreland Basin of SE France: New Perspectives on the Grès D'Annot and Related Systems. Geological Society Special Publications, London, pp. 65–96.

Babonneau, N., Savoye, B., Cremer, M., Klein, B., 2002. Morphology and architecture of the present canyon and channel system of the Zaire deep-sea fan. Mar. Petrol. Geol. 19, 445–467. https://doi.org/10.1016/S0264-8172(02)00009-0.

Baztan, J., Berné, S., Olivet, J.-L., Rabineau, M., Aslanian, D., Gaudin, M., Réhault, J.-P., Canals, M., 2005. Axial incision: the key to understand submarine canyon evolution (in the western Gulf of Lion). Marine and Petroleum Geology, The Gulf of Lions: an overview of recent studies within the French "Margins" Programme 22, 805–826. https://doi.org/10.1016/j.marpetgeo.2005.03.011.

Bourget, J., Zaragos, S., Ellouz-Zimmermann, N., Mouchot, N., Garlan, T., Schneider, J.-L., Lanfumey, V., Lallemand, S., 2011. Turbidite system architecture and sedimentary processes along topographically complex slopes: the Makran convergent margin. Sedimentology 58, 376–406. https://doi.org/10.1111/j.1365-3091.2010.01168.x.

Bouroullec, R., Cartwright, J.A., Johnson, H.D., Lansigu, C., Quémener, J.-M., Savanier, D., 2004. Syndepositional Faulting in the Grès D'Annot Formation, SE France: High-Resolution Kinematic Analysis and Stratigraphic Response to Growth Faulting, 221. Geological Society, London, Special Publications, pp. 241–265. https://doi.org/10.1144/GSL.SP.2004.221.0113.

Bouwmeester, M.J., Kane, I.A., Hodgson, D.M., Flint, S.S., Taylor, W.J., Soutter, E.L., McArthur, A.D., Poyatos-Moré, M., Marsh, J., Keavney, E., Brunt, R.L., Valdez-Buso, V., 2025. Evolution and architecture of an exhumed ocean-facing coarse-grained submarine canyon fill, Baja California, Mexico. Sedimentology 72, 189–226. https://doi.org/10.1111/sed.13231.

Bozetti, G., Kneller, B., Cronin, B.T., Li, P., McArthur, A., Xu, J., 2023. Lateral and temporal variations of a multi-phase coarse-grained submarine slope channel system, Upper Cretaceous Cerro Toro formation, southern Chile. J. Sediment. Res. 93, 161–186. https://doi.org/10.2110/jsr.2022.070.

Brownfield, M.E., 2016. Assessment of undiscovered oil and gas resources of the Niger Delta province, Nigeria and Cameroon, In: Geologic Assessment of Undiscovered Hydrocarbon Resources of Sub-Saharan Africa, Digital Data Series. U. S. Geological Survey, p. 24.

Bührig, L.H., Colombera, L., Patacci, M., Mountney, N.P., McCaffrey, W.D., 2022. A global analysis of controls on submarine-canyon geomorphology. Earth Sci. Rev. 233, 104150. https://doi.org/10.1016/j.earscirev.2022.104150.

Burke, K., 1972. Longshore drift, submarine canyons, and submarine fans in development of Niger Delta. AAPG (Am. Assoc. Pet. Geol.) Bull. 56, 1975–1983. https://doi.org/10.1306/819A41A2-16C5-11D7-8645000102C1865D.

Butler, R.W., Lickorish, W.H., Vinnels, J., McCaffrey, W., 2020. Untangling the Annot sand fairway: structure and stratigraphy of the eastern Champsaur basin (Eocene-Oligocene), French Alps. J. Geol. Soc. 177, 1197–1209.

Campredon, R., 1972. Les Formations Paléogènes Des Alpes Maritimes franco-italiennes. Thèse de l'Université de Nice.

Chen, J., Li, Q., Wu, S., Liu, S., 2024. Frontiers | The role of platform margin collapses and slope landslides in the initiation and evolution of submarine canyons. Front. Mar. Sci. 11, 1–16.

Chu, Y., Lin, W., Faure, M., Wang, Q., 2016. Detrital zircon U-Pb ages and Hf isotopic constraints on the terrigenous sediments of the Western Alps and their paleogeographic implications. Tectonics 35, 2734–2753. https://doi.org/10.1002/2016TC004276.

Chuber, S., 1987. Yoakum field, Dewitt and Lavaca counties. In: Typical Oil and Gas Fields of Southeast Texas, pp. 519–525.

Clayton, C.A., 2017. Linking Gulf of Mexico Margin Submarine Canyons to Regional Tectonics and Interaction of Peleogene Lower Wilcox High Frequency Sequences with the Yoakum Canyon. The University of Texas at Austin.

Clayton, C.A., Olariu, C., 2022. Tectonic preconditioning of recurrent large scale canyon incisions; example from Cretaceous and Paleogene of northern Gulf of Mexico. Mar. Geol. 453, 106909. https://doi.org/10.1016/j.margeo.2022.106909.

Cocherie, A., Rossi, Ph, Fanning, C.M., Guerrot, C., 2005. Comparative use of TIMS and SHRIMP for U-Pb zircon dating of A-type granites and mafic tholeiitic layered complexes and dykes from the Corsican Batholith (France). Lithos, Magmatic and Metamorphic Evolution of the Variscan Orogenic Crust 82, 185–219. https://doi.org/10.1016/j.lithos.2004.12.016.

Cockerill, I., 2019. Dorado: an overview of the largest oil discovery of the north west Shelf of Australia in the last 30 years. In: Presented at the Thte Seapex Exploration Conference, Singapore, p. 25.

Collot, J.-Y., Ratzov, G., Silva, P., Proust, J.-N., Migeon, S., Hernandez, M.-J., Michaud, F., Pazmino, A., Castillo, D.B., Alvarado, A., Khurama, S., 2019. The Esmeraldas canyon: a helpful marker of the Pliocene-Pleistocene tectonic deformation of the north Ecuador-southwest Colombia convergent margin. Tectonics 38, 3140–3166. https://doi.org/10.1029/2019TC005501.

Cornish, F.G., 2013. Do upper wilcox canyons support Paleogene isolation of the Gulf of Mexico. Gulf Coast Association of Geological Societies Transactions 63, 183–204.

Cornish, F.G., Lambiotte, L., 2016. Hydrocarbon traps associated with upper wilcox canyons and seismic response, mid-gulf Coast, Texas. Gulf Coast Association of Geological Societies Transactions 66, 731–737.

Cronin, B.T., Gürbüz, K., Gul, M., Çelik, H., Hurst, A., Kelling, G., 2007. Chapter 90: evolution of multiphase, winged, coarse-grained. Deep-water Canyons: Alikayasi Canyon, Turkey 357–362. https://doi.org/10.1306/1240978St563311.

Dailly, P., Lowry, P., Goh, K., Monson, G., 2002. Exploration and development of Ceiba field, Rio Muni basin, southern Equatorial Guinea. Lead. Edge 21, 1140–1146. https://doi.org/10.1190/1.1523753.

Deptuck, M.E., Sylvester, Z., Pirmez, C., O'Byrne, C., 2007. Migration-aggradation history and 3-D seismic geomorphology of submarine channels in the Pleistocene Benin-major Canyon, western Niger Delta slope. Marine and Petroleum Geology, Sinous Deep-Water Channels: Genesis, Geometry and Architecture 24, 406–433. https://doi.org/10.1016/j.marpetgeo.2007.01.005.

Di Celma, C., 2011. Sedimentology, architecture, and depositional evolution of a coarse-grained submarine canyon fill from the Gelasian (early Pleistocene) of the peri-Adriatic canyon, Offida, central Italy. Sediment. Geol. 238, 233–253. https://doi.org/10.1016/j.sedgeo.2011.05.003.

Di Celma, C., Teloni, R., Rustichelli, A., 2014. Large-scale stratigraphic architecture and sequence analysis of an early Pleistocene submarine canyon fill, Monte Ascension succession (Peri-Adriatic basin, eastern central Italy). Int. J. Earth Sci. 103, 843–875. https://doi.org/10.1007/s00531-013-0984-3.

Ding, W., Li, Jiabiao, Li, Jun, Fang, Y., Tang, Y., 2013. Morphotectonics and evolutionary controls on the Pearl river Canyon system, South China Sea. Mar. Geophys. Res. 34, 221–238. https://doi.org/10.1007/s11001-013-9173-9.

Dolson, J.C., He, Z., Horn, B.W., 2017. Advances and Perspectives on Stratigraphic Trap Exploration - Making the Subtle Trap Obvious, p. 52. Presented at the A.A.P.G. G.T. W., keynote paper, Muscat, Oman, Dec. 11-13, 2017.

Doust, H., Omatsola, E.M., 1990. Niger Delta, in: Divergent Passive Margin Bassins. A.A. P.G. Bull, pp. 239–248.

du Fornel, E., 2003. Reconstitution Sédimentologique Tridimensionnelle Et Simulation Stratigraphique Du Système Turbiditique Eocène Des Grès d'Annot (Alpes Méridionales). Université de Rennes, p. 1.

du Fornel, E., Joseph, P., Desaubliaux, G., Eschard, R., Guillocheau, F., Muller, C., Ravénne, C., Sztrákos, K., 2004. The southern Grès d'Annot outcrops (French Alps): an attempt at regional correlation. In: Joseph, P., Lomas, A. (Eds.), Deep-Water Sedimentation in the Alpine Foreland Basin of SE France: New Perspectives on the Grès D'Annot and Related Systems. Geological Society Special Publications, London, pp. 137–160.

Dumont, T., Schwartz, S., Guillot, S., Malusà, M., Jouvent, M., Monié, P., Verly, A., 2022. Cross-propagation of the western Alpine orogen from early to late deformation stages: evidence from the internal zones and implications for restoration. Earth Sci. Rev. 232, 104106. https://doi.org/10.1016/j.earscirev.2022.104106.

Dumont, T., Schwartz, S., Guillot, S., Simon-Labric, T., Tricart, P., Jourdan, S., 2012. Structural and sedimentary records of the Oligocene revolution in the Western Alpine arc. Journal of Geodynamics, Geodynamics and Orogenesis 56–57, 18–38. https://doi.org/10.1016/j.jog.2011.11.006.

Dumont, T., Simon-Labric, T., Authemayou, C., Heymes, T., 2011. Lateral termination of the north-directed Alpine orogeny and onset of westward escape in the Western Alpine arc: structural and sedimentary evidence from the external zone. Tectonics 30. https://doi.org/10.1029/2010TC002836.

Dunkl, I., Mikes, T., Frei, D., Gerdes, A., von Eynatten, H., 2009. PepiAGE: data reduction program for time-resolved U/Pb analyses. Software manual, p. 15. http://www.sedi.ment.uni-goettingen.de/staff/dunkl/zips/PepiAGE-introduction-c1.pdf.

Effimoff, I., Keall, J., 2018. Extended Abstract: SNE and FAN World Class Discoveries Offshore Senegal Herald A Major New Hydrocarbon Province, 61, p. 12.

Elliott, T., Apps, G., Davies, H., Evans, M., Ghibaudo, G., Graham, R.H., 1985. Field excursion B: a structural and sedimentological traverse through the tertiary foreland basin of the external Alps of south-east France. In: International Symposium on Foreland Basins - Excursion Guidebook. Frigboug, Switzerland, pp. 39–73.

Etienne, S., Mulder, T., Razin, P., Bez, M., Desaubliaux, G., Joussaume, R., Tournourd, E., 2013. Proximal to distal turbiditic sheet-sand heterogeneities: characteristics of associated internal channels. Examples from the Trois Évèchés area, Eocene-Oligocene Annot sandstones (Grès d'Annot), SE France. Marine and Petroleum Geology, Special Issue: Internal architecture, bedforms and geometry of turbidite channels 41, 117–133. https://doi.org/10.1016/j.marpetgeo.2012.03.007.

Ferry, J.-N., Babonneau, N., Mulder, T., Parize, O., Raillard, S., 2004. Morphogenesis of Congo submarine canyon and valley: implications about the theories of the canyons formation. Geodin. Acta 17, 241–251. https://doi.org/10.3166/ga.17.241-251.

Festa, A., Ogata, K., Pini, G.A., Dilek, Y., Alonso, J.L., 2016. Origin and significance of olistostromes in the evolution of orogenic belts: a global synthesis. Gondwana Res. 39, 180–203. https://doi.org/10.1016/j.gr.2016.08.002.

Festa, A., Ogata, K., Pini, G.A., Dilek, Y., Codegone, G., 2015. Late Oligocene–early Miocene olistostromes (sedimentary mélanges) as tectono-stratigraphic constraints to the geodynamic evolution of the exhumed Ligurian accretionary complex (Northern Apennines, NW Italy). Int. Geol. Rev. 57, 540–562. https://doi.org/10.1080/00206814.2014.931260.

Festa, A., Pini, G.A., Ogata, K., Dilek, Y., 2019. Diagnostic features and field-criteria in recognition of tectonic, sedimentary and diapric mélanges in orogenic belts and
exhumed subduction-accretion complexes. Gondwana Research, Mélanges: 100th anniversary of the inception of the term and concept 74, 7–30. https://doi.org/10.1016/j.gr.2019.01.003.

Ford, M., Duchêne, S., Gasquet, D., Vanderhaeghe, O., 2006. Two-phase orogenic convergence in the external and internal SW Alps. J. Geol. Soc. 163, 815–826. https://doi.org/10.1144/0016-76492005-0034.

Ford, M., Lickorish, W.H., 2004. Foreland Basin evolution around the western Alpine Arc. In: Joseph, P., Lomas, A. (Eds.), Deep-Water Sedimentation in the Alpine Foreland Basin of SE France: New Perspectives on the Grès D'Annot and Related Systems. Geological Society Special Publications, London, pp. 39–63.

Fulthorpe, C.S., Austin, J.A., Gosh, G.S., 2000. Morphology and distribution of Miocene slope incisions off New Jersey: are they diagnostic of sequence boundaries? GSA Bulletin 112, 817–828. https://doi.org/10.1130/0016-7606(2000)112#253C817;MADOMS%253E2.0.CO;2.

Galloway, W.E., Dingus, W.F., Paige, R.E., 1991. Seismic and depositional Facies of Paleocene-Eocene Wilcox group submarine canyon fills, northwest gulf Coast, U.S.A. In: Weimer, P., Link, M.H. (Eds.), Seismic Facies and Sedimentary Processes of Submarine Fans and Turbidite Systems, Frontiers in Sedimentary Geology. Springer, New York, NY, pp. 247–271. https://doi.org/10.1007/978-1-4684-8276-8_13.

Giacomini, F., Bomparola, R.M., Ghezzo, C., Guldbransen, H., 2006. The geodynamic evolution of the southern European variscides: constraints from the U/Pb geochronology and geochemistry of the lower Palaeozoic magmatic-sedimentary sequences of Sardinia (Italy). Contrib. Mineral. Petrol. 152, 19. https://doi.org/10.1007/s00410-006-0092-5.

Gong, C., Wang, Y., Zhu, W., Li, W., Xu, Q., Zhang, J., 2011. The central submarine Canyon in the Qiongdongnan basin, northwestern South China Sea: architecture, sequence stratigraphy, and depositional processes. Mar. Petrol. Geol. 28, 1690–1702. https://doi.org/10.1016/j.marpetgeo.2011.06.005.

Goodwin, R.H., Prior, D.B., 1989. Geometry and depositional sequences of the Mississippi Canyon, Gulf of Mexico. J. Sediment. Res. 59, 318–329. https://doi.org/10.1306/212F8F85-2B24-11D7-8648000102C1865D.

Gorini, C., Haq, B.U., dos Reis, A.T., Guizan Silva, C., Cruz, A., Soares, E., Grangeon, D., 2014. Late Neogene sequence stratigraphic evolution of the Foz do Amazonas Basin, Brazil. Terra Nova 26, 179–185. https://doi.org/10.1111/ter.12083.

Harris, P.T., Whiteway, T., 2011. Global distribution of large submarine canyons: geomorphic differences between active and passive continental margins. Mar. Geol. 285, 69–86. https://doi.org/10.1016/j.margeo.2011.05.008.

Hsieh, Y.-H., Liu, C.-S., Suppe, J., Byrne, T.B., Lallemand, S., 2020. The Chimei submarine canyon and fan: a record of Taiwan arc-continent collision on the rapidly deforming overriding plate. Tectonics 39, e2020TC006148. https://doi.org/10.1029/2020TC006148.

Hurford, A.J., Hunziker, J.C., Stöckhert, B., 1991. Constraints on the late thermotectonic evolution of the western Alps: evidence for episodic rapid uplift. Tectonics 10, 758–769. https://doi.org/10.1029/91TC00167.

Inglis, A., Lepvraud, E., Mousset, E., Salim, A., Vially, R., 1981. Etude Sédimentologique Des Grès D'Annot (Région De Colmars-les-Alpes Et Du Col De La Cayolle). ENSPM, p. 172.

Jackson, S.E., Pearson, N.J., Griffin, W.L., Belousova, E.A., 2004. The application of laser ablation-inductively coupled plasma-mass spectrometry to in situ U-Pb zircon geochronology. Chem. Geol. 211, 47–69.

Jean, S., Les Grès d'Annot au N.W. du Massif de l'Argentera-Mercantour (zone subalpine méridionale des Alpes occidentales françaises) - sédimentologie - paléontologie (Thèse). Université Scientifique et Médicale de Grenoble. P228. https://theses.hal.science/tel/00530042/.

Jean, S., Kerckhove, C., Perriaux, C., Ravenne, C., 1985. Un modèle paléogène de bassin à turbidites : les Grès d'Annot du NW du massif de l'Argentera-Mercantour. GA 61, 115–143.

Jobe, Z.R., Lowe, D.R., Uchytil, S.J., 2011. Two fundamentally different types of submarine canyons along the continental margin of Equatorial Guinea. Mar. Petrol. Geol. 28, 843–860.

Joseph, P., Callec, Y., Ford, M., 2012. Dynamic Controls on Sedimentology and Reservoir Architecture in the Foreland Basin - a Field Guide to the Eocene - Oligocene Grès D'Annot Turbidite System of SE France.

Joseph, P., Lomas, A., 2004. Deep-water sedimentation in the Alpine Foreland basin of SE France: new perspectives on the Grès d'Annot and related systems-an introduction. In: Joseph, P., Lomas, A. (Eds.), Deep-Water Sedimentation in the Alpine Foreland Basin of SE France: New Perspectives on the Grès D'Annot and Related Systems. Geological Society Special Publications, London, pp. 1–16.

Joseph, P., Ravenne, C., 2001. In: Lomas, Joseph, Clark, Broucke, Guillocheau, Gardiner, Ravenne, McCaffrey, Robin, Stanbrook (Eds.), Overview of the Grès D'Annot Basin. Presented at the Turbidite Sedimentation in Confined Settings: Research Meeting and Field Excursion to the Grès D'Annot, Held in Nice on 10-15 September 2001.

Jourdan, S., Bernet, M., Tricart, P., Hardwick, E., Paquette, J.-L., Guillot, S., Dumont, T., Schwartz, S., 2013. Short-lived, fast erosional exhumation of the internal western Alps during the late early Oligocene: constraints from geothermochronology of pro- and retro-side foreland basin sediments. Lithosphere 5, 211–225. https://doi.org/10.1130/L243.1.

Kerckhove, C., 1975. Sédimentation chaotique & tectogénese : les olistostromes des nappes de l'Embrunais - ubaye (Alpes occidentales françaises). In: Ixe Congrès International De Sédimentologie - Thème 4 - Tectonique Et Sédimentation. Nice, pp. 195–207.

Kerckhove, C., 1969. La "zone du Flysch" dans les nappes de l'Embrunais-Ubaye (Alpes occidentales). In: Géologie Alpine, pp. 5–204.

Kerckhove, C., Monjuvent, G., 1980. Carte géologique de la France (1:250 000), feuille de Gap 35.

Lansigu, C., 2000. Mécanismes De Déformation Dans Les Failles, Implications Sur Les Circulations De Fluides. in: Thèse de l'Université de Rennes 1, p. 337.

Li, X.-H., Faure, M., Lin, W., 2014. From crustal anatexis to mantle melting in the Variscan orogen of Corsica (France): SIMS U-Pb zircon age constraints. Tectonics 634, 19–30. https://doi.org/10.1016/j.tecto.2014.07.021.

Liu, C.-S., Lundberg, N., Reed, D.L., Huang, Y.-L., 1993. Morphological and seismic characteristics of the Kaoping Submarine Canyon. Mar. Geol. 111, 93–108. https://doi.org/10.1016/0025-3227(93)90190-7.

Ludwig, K.R., 2003. User's Manual for Isoplot 3.00, a Geochronological Toolkit for Microsoft Excel. Berkeley Geochronol. 4. Cent. Spec. Publ., pp. 25–32

Malusà, M.G., Polino, R., Zattin, M., Bigazzi, G., Martin, S., Piana, F., 2005. Miocene to present differential exhumation in the Western Alps: insights from fission track thermochronology. Tectonics 24. https://doi.org/10.1029/2004TC001782.

Marini, M., Patacci, M., Felletti, F., Decaris, A., McCaffrey, W., 2022. The erosionally confined to emergent transition in a slope-derived blocky mass-transport deposit interacting with a turbidite substrate, Ventimiglia Flysch formation (Grès d'annot system, north-west Italy). Sedimentology 69, 1675–1704. https://doi.org/10.1111/sed.12968.

Matesic, M., 2012. Depositional environment, thin bed potential, evaluation strategy at offshore fields. Bay of Bengal, Bangladesh. Search and Discovery. Article #50751.

Mazières, A., Gillet, H., Castelle, B., Mulder, T., Guyot, C., Garlan, T., Mallet, C., 2014. High-resolution morphobatymetric analysis and evolution of Capburell marine canyon head (southeast Bay of Biscay—French Atlantic Coast) over the last decade using descriptive and numerical modeling. Mar. Geol. 351, 1–12. https://doi.org/10.1016/j.margeo.2014.03.001.

McGee, R., Goodall, J., Molyneux, S., 2017. A re-evaluation of the lower to Middle Triassic on the cangade terrace, northern carnavon basin. The APPEA Journal 57, 263–276. https://doi.org/10.1071/AJ16003.

Menard, H.W., 1955. Deep-sea channels, topography and sedimentation. AAPG Bull. 39, 236–255.

Mercier, L., 2022. Le piégeage stratigraphique lié à l'incision des systèmes turbiditiques par des canyons à remplissage argileux, ou par des MTCs. Université Cote D'Azur.

Mercier, L., Dall'Asta, M., Migeon, S., Delhaye-Prat, V., Lafont, F., Rubino, J.-L., 2021. The Afam Canyon: a subsurface case of submarine rectangular drainage pattern and multiphase infilling (Tortonian, Nigeria). Presented at the 35th IAS Meeting of Sedimentology. https://doi.org/10.13140/RG.2.2.30787.73768. June 21-25, 2021, Pragure.

Mercier, L., Migeon, S., Dall'Asta, M., Praeg, D., Rubino, J.-L., Delhaye-Prat, V., Lafont, F., Akpi, T., 2023. Rectangular drainage pattern of a submarine canyon controlled by extensional tectonic structures: case study of the Afam incision surface (Tortonian, Niger Delta, Nigeria). Mar. Geol. 462, 107093. https://doi.org/10.1016/j.margeo.2023.107093.

Mercier, L., Migeon, S., Rubino, J.-L., Trevisan, J., Ravenne, C., Daghddevirenian, L., Popescu, S.-M., Melinte-Dobrinescu, M.C., Bubfik, M., 2024. Characterization of an Oligocene submarine canyon system and its controlling factors: the La Bonette canyon of the Southern French Alpine Foreland Basin. Mar. Petrol. Geol. 162, 106745. https://doi.org/10.1016/j.marpetgeo.2024.106745.

Morag, N., Avigad, D., Harlavan, Y., McWilliams, M.O., Michard, A., 2008. Rapid exhumation and mountain building in the Western Alps: petrology and 40Ar/39Ar geochronology of detritus from Tertiary basins of southeastern France. Tectonics 27. https://doi.org/10.1029/2007TC002142.

Morley, C.K., Leong, L.C., 2008. Evolution of deep-water synkinematic sedimentation in a piggyback basin, determined from three-dimensional seismic reflection data. Geosphere 4 (1), 939–962. https://doi.org/10.1130/GES000148.

Mulder, T., Callec, Y., Parize, O., Joseph, P., Schneider, J.-L., Robin, C., Dujoncqoy, E., Salles, T., Allard, J., Bonnel, C., Ducassou, E., Etienne, S., Ferger, B., Gaudin, M., Hanquiez, V., Linares, F., Marchés, E., Toucanne, S., Zaragosi, S., 2010. High-resolution analysis of submarine lobes deposits: Seismic-scale outcrops of the Lauzanier area (SE Alps, France). Sedimentary Geology, Lobs in deep-sea turbidite systems 229, 160–191. https://doi.org/10.1016/j.sedgeo.2009.11.005.

Mulder, T., Zaragosi, S., Garlan, T., Mavel, J., Cremer, M., Sottolichio, A., Sénéchal, N., Schmidt, S., 2012. Present deep-submarine canyons activity in the Bay of Biscay (NE Atlantic). Mar. Geol. 295–298, 113–127. https://doi.org/10.1016/j.margeo.2011.12.005. ISSN 0025-3227.

Muti, E., 1992. Turbidite sandstones. Università Di Parma. Agip-Istituto di Geologia.

Naranjo-Vesga, J., Ortiz-Karpf, A., Wood, L., Jobe, Z., Paniagua-Arroyave, J.F., Shumaker, L., Mateus-Tarazona, D., Galindo, P., 2020. Regional controls in the distribution and morphometry of deep-water gravitational deposits along a convergent tectonic margin. Southern Caribbean of Colombia. Mar. Petrol. Geol. 121, 104639. https://doi.org/10.1016/j.marpetgeo.2020.104639.

Normark, W.R., Carlson, P.C., 2003. Giant submarine canyons: is size any clue to their importance in rock record. GSA Bulletin 370, 1–15.

Ogata, K., Festa, A., Pini, G.A., Pogačnik, Ž., Lucente, C.C., 2019. Substrate deformation and incorporation in sedimentary mélanges (olistostromes): examples from the northern Apennines (Italy) and northwestern Dinarides (Slovenia). Gondwana Research, Mélanges: 100th anniversary of the inception of the term and concept 74, 101–125. https://doi.org/10.1016/j.gr.2019.03.001.

Onézime, J., Faure, M., Crévola, G., 1999. Étude pétro-structurale du complexe granitique Rouet - plan-de-la-tour (massifs des Maures et du Tanneron occidental, Var). Comptes Rendus Acad. Sci. - Ser. IIA Earth Planet. Sci. 328, 773–779. https://doi.org/10.1016/S1251-8050(99)80170-0.

Orife, J.M., Avbovbo, A.A., 1982. Stratigraphic and Unconformity Traps in the Niger Delta, 130, pp. 251–265.

Paquette, J.-L., Ménot, R.-P., Pin, C., Orsini, J.-B., 2003. Episodic and short-lived granitic pulses in a post-collisional setting: evidence from precise U–Pb zircon dating through
a crustal cross-section in Corsica. Chem. Geol. 198, 1–20. https://doi.org/10.1016/
S0009-2541(02)00401-1.

Park, Y., Yoo, D., Kang, N., Yi, B., 2019. Origin and evolution of stacked cut-and-fill structures on the Southwestern margin of the ulleung basin, East sea (Japan sea). J. Sediment. Res. 89, 679–700. https://doi.org/10.2110/jsr.2019.36.

Peakall, J., McCaffrey, B., Kneller, B., 2000. A process model for the evolution, morphology, and architecture of sinuous submarine channels. J. Sediment. Res. 70, 434–448. https://doi.org/10.1306/2DC4091C-0E47-11D7-8643000102C1865D.

Peres, W.E., Arso, L.R., 1986. O uso da sísmica na Delimitação De Acumulações De Hidrocarbonetos na Bacia De Campos, Brazil, 15. Boletin Tecnico Arpel, pp. 101–115.

Perotti, E., Bertok, C., d'Atri, A., Martire, L., Piana, F., Catanzariti, R., 2012. A tectonically-induced Eocene sedimentary mélange in the west Ligurian Alps, Italy. Tectonophysics, Chaos and Geodynamics: Melanges, Mélange Forming Processes and Their Significance in the Geological Record 568–569, 200–214. https://doi.org/10.1016/j.tecto.2011.09.005.

Pini, G.A., Ogata, K., Camerlenghi, A., Festa, A., Lucente, C.C., Codegone, G., 2012. Sedimentary mélanges and fossil mass-transport complexes: a key for better understanding submarine mass movements? In: Yamada, Y., Kawamura, K., Ikehara, K., Ogawa, Y., Urgeles, R., Mosher, D., Chaytor, J., Strasser, M. (Eds.), Submarine Mass Movements and their Consequences. Springer, Netherlands, Dordrecht, pp. 585–594. https://doi.org/10.1007/978-1-4684-8276-8_6.

Posamentier, H.W., Erskine, R.D., Mitchum, R.M., 1991. Models for submarine-fan
deposition within a sequence-stratigraphic framework. In: Seismic Facies and
Sedimentary Processes of Submarine Fans and Turbidite Systems, Frontiers in
Sedimentary Geology. Springer, New York, NY, pp. 127–136. https://doi.org/
10.1007/978-1-4684-8276-8_2.

Pratson, L.F., Coakley, B.J., 1996. A model for the headward erosion of submarine canyons induced by downslope-eroding sediment flows. Geol. Soc. Am. Bull. 108, 225-234.

Pratson, L.F., Ryan, W.B.F., Mountain, G.S., Twichell, D.C., 1994. Submarine canyon initiation by downslope-eroding sediment flows: evidence in late Cenozoic strata on the New Jersey continental slope. GSA Bulletin 106 (2), 395–412. https://doi.org/10.1130/0016-7606(1994)106%253C0395:SCIBD%253E2.3.CO.

Rasmussen, E.S., 1994. The relationship between submarine canyon fill and sea-level change: an example from Middle Miocene offshore Gabon, West Africa. Sediment. Geol. 90, 61–75. https://doi.org/10.1016/0037-0738(94)90017-5.

Ratzov, G., Gosson, M., Collot, J.-Y., Migeon, S., 2012. Late Quaternary geomorphologic evolution of submarine canyons as a marker of active deformation on convergent margins: the example of the South Colombian margin. Mar. Geol. 315–318, 77–97. https://doi.org/10.1016/j.margeo.2012.05.005.

Ravenne, C., Vially, R., Riché, P., Trémolières, P., 1987. Sédimentation et Tectonique
Dans le Bassin Marin Éocène supérieur-Oligocène des Alpes du Sud, 42. Revue de
l'Institut Français du Pétrole, pp. 529–553.

Rossi, P., Cocherie, A., Fanning, C.M., Deloule, É., 2006. Variscan to eo-Alpine events recorded in European lower-crust zircons sampled from the French Massif central and Corsica, France. Lithos, Geochronology of Orogenic Processes 87, 235–260. https://doi.org/10.1016/j.lithos.2005.06.009.

Roure, J., Autran, A., Prost, A., Rossi, J., Rousset, C., 1980a. Carte Géologique de la France (1:250 000), feuille de Nice 40.

Roure, J., Blanc, J.-J., 1979. Carte Géologique de la France (1:250 000). feuille de Marseille 39.

Roure, J., Chiron, J.-C., Camus, G., Kieffer, G., Masse, J.-P., Mergoil, J., Monjuvent, G., Rousset, C., 1980b. Carte Géologique de la France (1:250 000). feuille de Valence 34.

Schmid, S.M., Pfiiffner, O.A., Froitzheim, N., Schönborn, G., Kissling, E., 1996. Geophysical-geological transect and tectonic evolution of the Swiss-Italian alps. Tectonics 15, 1036–1064. https://doi.org/10.1029/96TC00433.

Shepard, F.P., 1981. Submarine canyons: multiple causes and long-time persistence. AAPG (Am. Assoc. Pet. Geol.) Bull. 65, 1062–1077. https://doi.org/10.1306/03B59459-16D1-11D7-8645000102C1865D.

Shepard, F.P., 1972. Submarine canyons. Earth Sci. Rev. 8, 1–12. https://doi.org/
10.1016/0012-8252(72)90032-3.

Shepard, F.P., Dill, R.F., 1966. Submarine Canyons and Other Sea Valleys. Rand McNally
Comp., Chicago.

Sinclair, H.D., Sayer, Z.R., Tucker, M.E., 1998. Carbonate Sedimentation During Early Foreland Basin Subsidence: the Eocene Succession of the French Alps, 149. Geological Society, London, Special Publications, pp. 205–227. https://doi.org/10.1144/GSL.SP.1999.149.01.11.

Siwek, P., Waškowska, A., Wendorff, M., 2023. Mud-rich low-density turbidites in structurally-controlled intraslope mini-basin: the influence of flow containment on depositional processes and sedimentation patterns (Szczawa, Oligocene, Polish outer carpathians). Sedimentology 70, 1741–1784. https://doi.org/10.1111/sed.13095.

Sneider, J.S., 2013. Shelf margin deltas and associated deep-water deposits: implications on reservoir distribution and hydrocarbon entrapment, block VI-1, ulleung basin, East sea, South Korea. https://doi.org/10.5724/gcs.03.23.0473.

Sztrákos, K., du Fornel, E., 2003. Stratigraphie, Paléoécologie Et Foraminifères Du Paléogène Des Alpes Maritimes Et Des Alpes de Haute-Provence (Sud-Est de la France), 46, pp. 229-267.

Taylor, W.J., Hodgson, D.M., Peakall, J., Kane, I.A., Morris, E.A., Flint, S.S., 2024. Unidirectional and combined transitional flow bedforms: controls on process and distribution in submarine slope settings. Sedimentology 71, 1329–1362. https://doi.org/10.1111/sed.13177.

Tinterri, R., Mazza, T., Magalhaes, P.M., 2022. Contained-reflected megaturbidites of the Marnoso-areناcina formation (Contessa key bed) and Helminthoid flysches (Northern Apennines, Italy) and Hecho group (South-Western pyrenees). Front. Earth Sci. 10. https://doi.org/10.3389/feart.2022.817012.

Tournadour, E., Mulder, T., Borgomano, J., Gillet, H., Chabaud, L., Ducassou, E., Hanquiez, V., Etienne, S., 2017. Submarine canyon morphologies and evolution in modern carbonate settings: the northern slope of little Bahama Bank, Bahamas. Mar. Geol. 391, 76–97. https://doi.org/10.1016/j.margeo.2017.07.014.

Trincardi, F., Foglini, F., Verdicchio, G., Asioli, A., Correggiari, A., Minisini, D., Piva, A., Remia, A., Ridente, D., Taviani, M., 2007. The impact of cascading currents on the Bari Canyon System, SW-Adriatic Margin (Central Mediterranean). Mar. Geol. 246 (2-4), 208–230. https://doi.org/10.1016/j.margeo.2007.01.013. ISSN 0025-3227.

Trullenque, G., Kunze, K., Heilbronner, R., Stünitz, H., Schmid, S.M., 2006. Microfabrics of calcite ultramylonites as records of coaxial and non-coaxial deformation kinematics: examples from the Rocher de l'Yret shear zone (Western Alps). Tectonophysics 424, 69–97. https://doi.org/10.1016/j.tecto.2006.06.004.

Van de Vyver, C., Carpentier, C., Ford, M., Vergés, J., Melinte-Dobrinescu, 2024.
Sedimentology and structure of the Paleogene Nummulitic series of Corsica:
reconstruction of the southern termination of the Western Alpine Foreland basin -
van de Vyver - 2024 - basin Research - wiley Online Library. Basin Res. 36. https://
doi.org/10.1111/bre.12898.

Vinnels, J.S., Butler, R.W.H., McCaffrey, W.D., Lickorish, W.H., 2010a. Sediment distribution and architecture around a bathymetrically complex basin: an example from the eastern champsaur basin, Se France. J. Sediment. Res. 80, 216–235. https://doi.org/10.2110/jsr.2010.025.

Vinnels, J.S., Butler, R.W.H., McCaffrey, W.D., Paton, D.A., 2010b. Depositional processes across the Sinú Accretionary Prism, offshore Colombia. Mar. Petrol. Geol. 27, 794–809. https://doi.org/10.1016/j.marpetgeo.2009.12.008.

Weimer, P., Link, M.H., 1991. Global petroleum occurences in submarine fans and turbidite systems, in: seismic facies and sedimentary processes of submarine fans and turbidite systems. In: Weimer, P., Link, Martin H. (Eds.), Frontiers in Sedimentology Geology, pp. 9–67.

Wiedenbeck, M.A.P.C., Alle, P., Corfu, F.Y., Griffin, W.L., Meier, M., Orbeli, F.V., Spiegel, W., 1995. Three natural zircon standards for U-Th-Pb, Lu-Hf, trace element and REE analyses. Geostand. Newsl. 19, 1–23.

Wynn, R.B., Cronin, B.T., Peakall, J., 2007. Sinuous deep-water channels: Genesis, geometry and architecture. Marine and Petroleum Geology, Sinuous Deep-Water Channels: Genesis, Geometry and Architecture 24, 341–387. https://doi.org/10.1016/j.marpetgeo.2007.06.001.

Zecchin, M., Caffau, M., Roda, C., 2011. Relationships between high-magnitude relative sea-level changes and filling of a coarse-grained submarine canyon (Pleistocene, Ionian Calabria, Southern Italy). Sedimentology 58, 1030–1064. https://doi.org/10.1111/j.1365-3091.2010.01194.x.