|Synonyms:||Silex Crétacé supérieur Est - Sénonien (Campanien)|
|Material (geologic):||Campanian (Senonian, Late Cretaceous) flint|
Foto: Jehanne Féblot-Augustins, 2005.
|Macroscopically, this type, which occurs only at En Lachat, differs from CE1a mainly in terms of colour: it is a darker grey N4 to N5, a feature resulting from impregnation by organic matter.|
|Structure:||No particular structure.|
|Matrix:||Depending on area, either colourless and subtranslucent, or dark grey.|
|Grains:||10 to 12.5 %, whitish skeletal grains, subangular with high sphericity (200 to 300 µ), rare clasts (500 to 1000 µ).|
|Grain composition:||Numerous planktonic foraminifera (biserial Heterohelicidae and small globose forms), several discrete punctated spheres of 250 µ, numerous monaxon and triaxon sponge spicules, occasionally thick-walled, sea urchin radioles, echinoderm fragments.|
|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:||Villes / En Lachat, France, Ain department|
|Synonyms:||Sampling site Bugey 49 after Féblot-Augustins|
|Geographical description:||The source is located in some fields, under a kilometre away in a northwesterly direction from the hamlet/village of Villes, some eight kilometres SW of Bellegarde-sur-Valserine.|
(Lambert zone II, NTF)
This corresponds roughly with
The coordinates given were taken from a large-scale map, and are within approx. 50 metres of the actual spot.
The latitude/longitude coordinates are a direct transformation of these data on WGS84 and are accurate to the same level; the 1-second precision is given to prevent any rounding-errors.
The location can be found on the 1:25 000 topographical map sheet 3329 W of the French Institut Géographique National.
According to the geological map, the substrate belongs to the Early to Middle Miocene (without distinction between Burdigalian and Helvetian), unit m1b-2a.
Map of all sampled localities of Late Cretaceous flint in the Bugey (PDF, 54 KB, opens in new window).
|Type of source:||Secondary. Redeposited Campanian flint from Miocene sediments.|
|Other types of flint:||The flint here constitutes quite a mixed lot, with predominantly Late Cretaceous material like CE1a, CE1c, CE2, CE3, CE4a, CE4b, and CE5, but also Hauterivian (Early Cretaceous) material of the Ht3-type.|
Foto: Jehanne Féblot-Augustins, 2005
|Last modified on:
November 15, 2005
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