|Material (geologic):||Middle Jurassic (Early to Middle Bajocian) flint/chert|
Foto: Jehanne Féblot-Augustins, 2005.
|Mode of occurrence:||Joining nodules forming siliceous beds 6 cm thick.|
|Cortex:||Rough, light reddish tan, 1 cm thick, transition sharp.|
|Colour:||Dark (bluish) grey (N4).|
|Pattern:||Laminations 2 to 4 mm thick, lighter hues alternating with darker tones.|
|Appearance:||Homogeneous material, dull and opaque, rather rough and coarse-grained.|
|Structure:||Laminated, corresponding to differences in colour and texture, irregular bands of more or less milky matrix (recrystallized as chalcedony); frequent micro-vugs.|
|Texture:||Wackestone (milky zones) to packstone.|
|Matrix:||Milky to more translucent.|
|Grains:||20 to 40 %, irregularly shaped, rounded, poorly sorted (100 to 400 µ, overall impression 3-400 µ).|
|Grain composition:||Peloids, foraminifera showing as "ghosts" outlined by impurities, numerous monaxon or triaxon sponge spicules, thick-walled and recrystallized as chalcedony; abundant grains of iron oxides.|
|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:||Jujurieux / La Courbattière, France, Ain department|
|Synonyms:||Sampling site Bugey 7 after Féblot-Augustins|
|Geographical description:||The source is located on a wooded slope facing the hamlet of La Courbattière, approx. 1 km southeast of Jujurieux.|
(Lambert zone II, NTF)
This corresponds roughly with
The coordinates given were taken from a large-scale map, and are within approx. 50 to 100 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 suggested higher precision is given to avoid the introduction of a transformation error.
The location can be found on the 1:25 000 topographical map sheet 3230 W of the French Institut Géographique National.
According to the geological map, the substrate belongs to unit l9b-J1b (Early Aalenian and Early-Middle Bajocian).
Map of all sampled localities of Bajocian flint in the Bugey (PDF, 190 KB, opens in new window).
|Type of source:||Primary.|
|Other types of flint:||All flint from this source belongs to type Bj2, and is, up to now, the only occurrence of this type of material.|
Foto: Jehanne Féblot-Augustins, 2005
|Last modified on:
November 15, 2005
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