Oise amber
Oise amber is a collective term that is often used in the literature for amber from Lower Oocene deposits from various locations in northern France.
Find area and geology
The amber lies in a sandstone formation from the Lower Eocene (Sparnacium, approx. 53 million years old). The known sites are widely scattered, mainly north of Paris. One of these sites in the Oise department was scientifically investigated at the end of the 1990s and approx. 350 kg of amber were extracted from the outcrops there, which are no longer accessible today. The material is in the Natural History Museum of Paris .
Botanical origin
From the composition of the accompanying flora at the main location of the amber ( Houdancourt ) it is concluded that the tree supplying the resin is probably Aulacoxylon sparnacense , an extinct member of the Combretaceae or Leguminosae . Since Oise-Bernstein contains the diterpene quesnoin , it is concluded that the resin donor is related to the carob tree ( Caesalpinioideae ) Hymenaea oblongifolia , which is widespread in South America today . The infrared spectrum of amber also shows similarities to Hymenaea (here to Copal with this origin).
Organic inclusions
The mostly clear and often occurring in the form of stalactites amber is described as rich in fossils. More than 20,000 inclusions could be obtained from the amber collection mentioned above. The fossil fauna, which is rich in forms, differs quite significantly from that of the largely younger Baltic amber. This is attributed both to a faster evolution rate of the insects, which is associated with a clear and rapid climate change following the Paleocene / Eocene temperature maximum , and to differences in the plant community of the amber forests, which indicate different habitats .
literature
- André Nel & Nicolas Brasero: Oise Amber. In: Biodiversity of fossils in amber from the major world deposits. Pp. 137-148. Manchester (UK) 2010. ISBN 978-0-95586364-6 .
- Nicolas Brasero, André Nel & Denis Michez: Insects from the Early Eocene amber of Oise (France): diversity and palaeontological significance. In: Denisia 26, Neue Serie 86, pp. 41–52, Linz 2009.
Individual evidence
- ↑ Jean Jossang, Hakima Bel-Kassaoui, Akino Jossang, Mannan Seuleiman, André Nel: Quesnoin, a Novel Pentacyclic ent-Diterpene from 55 Million Years Old Oise Amber. In: The Journal of Organic Chemistry. 73, 2008, p. 412, doi : 10.1021 / jo701544k .