|Synonyms:||Silex Crétacé supérieur Nord - Sénonien (Campanien)|
|Material (geologic):||Late Cretaceous (Senonian, Campanian) flint|
Foto: Jehanne Féblot-Augustins, 2005.
|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).|
|Appearance:||Homogeneous, dull and opaque, a little rough, medium-grained.|
|Structure:||No particular structure.|
|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.
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.|
|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.|
east/x 836,7 to 836,8
north/y 2124 to 2124,2
(Lambert zone II, NTF)
This corresponds roughly with
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.
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: