Sprecher
Beschreibung
Rivecourt and Le Quesnoy (Oise, France) are two fossil sites located in the northeastern part of the Paris Basin that have yielded very rich floras and faunas. Rivecourt is dated to the uppermost Thanetian and Le Quesnoy to the lowermost Ypresian, making these sites particularly suitable for investigating vegetation changes across the Paleocene-Eocene Thermal Maximum in Europe. In addition, the two deposits represent contrasting paleoenvironments: Rivecourt corresponds to a meandering river system associated with a subtropical forest whereas Le Quesnoy represents a fluvio-lacustrine subtropical wetland.
Approximately 40 hardwood and stem specimens from each site were prepared as thin sections from resin-embedded wood fragments and described using light microscopy and IAWA terminology. The Le Quesnoy assemblage is anatomically homogeneous and dominated by diffuse-porous woods characterized by simple perforation plates, alternate intervessel pitting, rays uni- to triseriate and randomly distributed vessels commonly forming short radial multiples. In contrast, Rivecourt assemblage displays greater anatomical diversity, including fagalean-type woods with exclusively solitary vessels radially arranged, woods with scalariform perforation plates and very small vessels, as well as comparable to those of Le Quesnoy. The Arecaceae of both sites are likely similar.
Both assemblages are taxonomically diverse and mainly resemble extant tropical families, such as Sapotaceae, Combretaceae, Rubiaceae, Sapindaceae, Rhamnaceae or Coryphoideae. These results provide new insights into the composition and ecological structure of European subtropical forests across the PETM and will be compared with other plant organs from both sites.