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CN6

Material name:	CN6
Synonyms:	Silex Crétacé supérieur Nord - Sénonien (Campanien)
Material (geologic):	Late Cretaceous (Senonian, Campanian) flint

Foto: Jehanne Féblot-Augustins, 2005.

Sampled sites:

Chatanay

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Material description

Mode of occurrence: Entirely patinated nodule fragment (cream-coloured patina).

Cortex: Remaining cortex is thin and worn, smooth, stained yellowish red, and highlighted by a white 1 cm thick desilicified band forming a sharp transition with the flint.

Colour: Light grey (2.5Y N6.5/2).

Pattern: Featureless.

Appearance: Homogeneous, dull and opaque, a little rough, medium-grained.

Structure: No particular structure.

Texture: Wackestone.

Matrix: Opaque.

Grains: 15 to 20 %, white or more seldom stained yellow by iron oxides, rounded with high to medium sphericity, contained between 100 and 250 µ.

Grain composition: frequent thin-walled monaxon spicules, less frequent triaxon spicules, numerous globose planktonic foraminifera (e.g. Hedbergella ?), some benthic foraminifera (Lenticulinea), ostracods and bryozoan fragments; abundant ligneous debris, a few iron oxides.

Microphotograph of Globotruncanidae
Globotruncanidae (Hedbergella ?)
in a CN4c flint type.
Highly silicified.

Photo: A. Arnaud Vanneau,
(Laboratoire de Géodynamique des Chaînes Alpines, Grenoble)

Determination: M. Caron, Université de Fribourg.

Further information: Click here for the original French description (opens in a new window), or here for more information on the attributes used in the description (use your browser's "BACK"-button to return here).

Citing: Information on citing this page can be found here.

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Chatanay

Locality:	Poncin / Chenavel - Chatanay, France, Ain department
Synonyms:	Sampling site Bugey 48 after Féblot-Augustins
Geographical description:	The sampling-site is located directly adjacent to a narrow road, a bit over a kilometre to the (S)SW of Poncin.
Geographical co-ordinates:	east/x 836,7 to 836,8 north/y 2124 to 2124,2 (Lambert zone II, NTF) This corresponds roughly with Lat. 46° 04' 32" N Long. 005° 23' 52" E (WGS84)
Co-ordinate precision:	As the site is a few hectares in size, precision is not of the highest importance, but the coordinates lie well within the area. The geographical coordinates point to a spot near the centre of the site. The location can be found on the 1:25 000 topographical map sheet 3230 W of the French Institut Géographique National.
Geology:	The material from this site can be classified as surface-collected flint or in eroded gulleys, Chenavel sector, clays-with-flint of various geological origins (Early and Late Cretaceous); Unit S (Rs). Map of all sampled localities of Late Cretaceous flint in the Bugey (PDF, 54 KB, opens in new window).
Type of source:	Secondary.
Other types of flint:	Besides the Campanian CN1a material, several types of Late Cretaceous material can be found here (CN1a, CN2a, CN2c, CN4a and CN4b), as well as Early Cretaceous Ht3 flint.

Foto: Jehanne Féblot-Augustins, 2005

Last modified on:
November 15, 2005

Contents primarily by:
Jehanne Féblot-Augustins

Comments to:

Mode of occurrence:	Entirely patinated nodule fragment (cream-coloured patina).
Cortex:	Remaining cortex is thin and worn, smooth, stained yellowish red, and highlighted by a white 1 cm thick desilicified band forming a sharp transition with the flint.
Colour:	Light grey (2.5Y N6.5/2).
Pattern:	Featureless.
Appearance:	Homogeneous, dull and opaque, a little rough, medium-grained.
Structure:	No particular structure.
Texture:	Wackestone.
Matrix:	Opaque.
Grains:	15 to 20 %, white or more seldom stained yellow by iron oxides, rounded with high to medium sphericity, contained between 100 and 250 µ.
Grain composition:	frequent thin-walled monaxon spicules, less frequent triaxon spicules, numerous globose planktonic foraminifera (e.g. Hedbergella ?), some benthic foraminifera (Lenticulinea), ostracods and bryozoan fragments; abundant ligneous debris, a few iron oxides.

	Globotruncanidae (Hedbergella ?) in a CN4c flint type. Highly silicified.
	Photo: A. Arnaud Vanneau, (Laboratoire de Géodynamique des Chaînes Alpines, Grenoble) Determination: M. Caron, Université de Fribourg.

Further information:	Click here for the original French description (opens in a new window), or here for more information on the attributes used in the description (use your browser's "BACK"-button to return here).
Citing:	Information on citing this page can be found here.