Grow faults affecting geometry and sequence ...

International Meeting of Sedimentology (IAS-ASF), October 10-12th, 2017 - Toulouse, France

Grow faults affecting geometry and sequence stratigraphic record on a carbonate platform edge: South Vercors Urgonian platform, SE France Serge Ferry Lithostratigraphic units of Arnaud (1981), centre of the Archiane Cirque

Grd Veymont

(late fault)

Mt Aiguille

col du Rousset prese nt-day Urgonian

c liff

Urgonian platform (max progradation) NW

(Poster presentation)

Bi6-2, 3...

Chichiliane

inferred growth fault

SE

a

Die

T1

slump scar

slump scar

(Bievre & Quesne 2004)

Archiane

La

T2

Bi6-1

Menée Pass Combau

Glandasse

D rô

Les Nonnières Bénevise

me (R i

Menée

v.)

Tithonian lms. (foreground)

(Quatre Chemins)

La Montagnette

T3

b

Bi5

Châtillon-en-Diois

The slump scar on the southwestern side of the Glandasse (Bievre & Quesne, 2004)

ugh o r T

Vocontian

N

high of the cliff ≈ 400 m

10 km

Transects: T1, Archiane west; T2, Archiane east; T3, Montagnette-Combau occurrence of Urgonian facies (corals, rudistids) atop of Bi 5 (a) and Bi 6-1 (b) units

Changes in the internal geometry of the Bi 5 unit along three N-S transects

S

N Bi 6-2, -3, ...

Bi 6-1

Platform edge affected by slump scars and rotational deformations due to growth fauts These explain the local distorsion of the basic sequence stratigraphic organisation of depositional sequences (Bi 5a and Bi 6-1) These also explain the local occurrence of pure tidal facies (Bi 6-1) in periplatformal calcarenite deposits otherwise swell-dominated

Bi 6-2, -3, ...

Bi 6-1

aggrading

Bi 6-1

Bi 5 prograding & aggrading

Bi 5

Archiane-west

Bi 5 Bi 6-2

fastly prograding l L fal

fine

RS

Transect T1

Montagnette

RSL fall surface platform flooding

Bi 6-1

e surfac ed -grain

Archiane-East

RSL fall surface platform flooding

lms.

slope wedge (Fontaine Colombette) retrograding

aggrading

Bi 5

aggrading

T accommodation reversal surface

prograding

steadily prograding

prograding R

basal sigmoidal wedge RSL fall surface

slope deposits

true Urgonian coral/rudistid facies (in blue) interpreted as platform flooding facies

retrograding

N

2 - deformation of the geometry due to a grow fault transgression surface

prograding

Bi 6-2 (aggrading)

top Bi 6-1

Bi 6-2 (prograding)

FC drowning

transgression surface post Bi 5

Belvédère

Bi 5 (aggrading wedge)

inferred synsedimentary grow fault

S

FC drow

ning

Bi 5 (prograding)

panorama

RSL fall surface

Bi 5 (prograding)

1 - fast progradation of calcarenite on a Relative Sea Level (RSL) fall surface

(FC, Fontaine Colombette “Marls“) hinge point (Belvédère)

Transect T2

prograding calcarenite of La Montagnette

S

S

N

N

Bi5

sea level 1 (high stand) FG Marls

sec

tion

stormweather wave base 1

Bergerie de Combau

lower FC transgression surface

c

b

stormweather wave base 2

a

by-pass

c

a

b opposed dips in underlying grey limestone

Transect T3

marlstone

inferred synsedimentary grow fault (first rotational mvt)

section bergerie de Combau

S

Rocher de Combau

surface deformed by rotational mvt of a grow fault updip

updip equiv. of upper FC “Marls“

équiv. Bi 6-1 (this study) “Bi 6-1“ (Arnaud 1981)

surface deformed by rotational mvt of a grow fault

lower FC “Marls“ (Arnaud 1981)

N - Combau (Serre de Beaupuy)

protected tidal facies (metre-scale megaripples)

S - Montagnette

N

base of Bi 6-2

Base Bs 100

200

updip equiv. of upper FC Marls Bi6

100

“Bi6-1“ of Arnaud

50

coarse-grained, poorly-sorted packstone 50

150

0

100

“Bi5“ of Arnaud

rotational mvt (second stage)

lower FC “Marls“ (this study)

slope lms.

toe of Montagnette clinoforms

top Bi 5 (this study)

50

0

Interpretation of the curious occurrence of protected tidal calcarenite in unit Bi 6-1 at Rocher de Combau

affiliation of author: Université de Lyon, France (retired)

Montagnette uooer clinoforms a, b, c

0

top Bi 5 (Arnaud 1981)

true available space

geometries of calcarenite wedges depending on available space after a RSL fall

base of Bi 6-2

Bi 6-2, 6-3,...

theoretical available space

scree

ravines

Rocher de Combau

huge clinoforms

equiv Bi6-1 of Archiane

yellowish

sigmoidal offlap of bedded tempestites

lower Fontaine Colombette

Rocher de Combau

sea level 2 (low stand)

rotational mvt (first stage)