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Material name: Val
Synonyms: N/A
Material (geologic): late Valanginian (Early Cretaceous) of the so-called "russet limestones"

Detail of Valanginian flint
Foto: Jehanne Féblot-Augustins, 2005.

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Material description

Mode of occurrence: Compact 20 cm thick beds amalgamated into Oligocene conglomeratic deposits.
Cortex: <1 mm, siliceous, yellowish brown.
Colour: Yellowish brown hues (10YR 5/4).
Pattern: Slightly mottled, numerous inclusions visible to the naked eye.
Appearance: Homogeneous material, dull and opaque, a little rough and medium-grained.
Structure: Faintly laminated with slight variation in colour due to a differential impregnation by iron oxides, faint fluidal arrangement of grains.
Texture: Wackestone/packstone.
Matrix: Semi-opaque to glassy, "jellied" aspect.
Grains: 40 %, white, yellow to orangey yellow, subangular and irregularly shaped, very poorly sorted with a maximum of 7 mm, generally contained between 250 and 500-1000 µ.
Grain composition: Well preserved colonial Cyclostoma bryozoans, serpulids and worm traces, micritized pelecypod and brachiopod debris, echinoderm fragments, sea urchin radioles, rare sponge spicules, rare foraminifera (Nodosarianidea, Lenticulinea); clasts surrounded by a halo of recrystallization, some 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.

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Les Baraques
Locality: Andert-et-Condon / Andert - Les Baraques
Synonyms: Sampling site Bugey 51 after Féblot-Augustins
Geographical description: N/A
Geographical co-ordinates: east/x 858,35
north/y 2092
(Lambert zone II, NTF)

This corresponds with
Lat. 45° 46' 45" N
Long. 005° 39' 34" E

Co-ordinate precision: The coordinates given were taken from a large-scale map, and are within 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, so don't be deceived by the apparently high precision to the second.

The location can be found on the 1:25 000 topographical map sheet 3231 E of the French Institut Géographique National.

Geology: According to the geological map, the substrate dates to the Oligocene (unit g), but the flint itselfs comes originally from Early Cretaceous (Late Valanginian) "russet limestones" (calcaires roux).

Map of all sampled localities of Early Cretaceous flint in the Bugey (PDF, 300 KB, opens in new window).

Type of source: Secondary.
Other types of flint: Apart from the Val-type of flint, also reworked Late Cretaceous (Senonian) flint of the CC2-type can be found here.
  cherty flint
Foto: Jehanne Féblot-Augustins, 2005
Valanginian flint
Foto: Jehanne Féblot-Augustins, 2005


Last modified on:
November 15, 2005
Contents primarily by:
Jehanne Féblot-Augustins
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