Author	Fechner, G.G.
Year	1989
Journal	Documenta Naturae, 53: 136 pp.(München)
Title	Palynologische Untersuchungen im Alb/Cenoman- Grenzbereich von Rüthen (NW-Deutschland) und La Vierre (SE-Frankreich).

Abstract Fechner, G.G., 1989; Palynologische Untersuchungen im Alb/Cenoman- Grenzbereich von Rüthen (NW-Deutschland) und La Vierre (SE-Frankreich). Documenta Naturae, 53: 136 pp.(München) This work deals with a palyno-sedimentological and quantitative stratigraphic research on two geological sections containing very different geological, sedimentological, paleoecological, and paleogeographical data. The selected Mid-Cretaceous (Albian/Cenomanian boundary) lithological sections are now more than 800 km apart. The R³then section (NW Germany, boreal) is ca. 4 m thick and represents a transgressive, neritic sequence. The La Vierre section (SE France, Tethys) is ca. 12 m thick and contains a hemipelagic sequence. Using several parallel and independent palynosedimentological techniques, on the two different sections, an attempt was made to relate palynology, sedimentology, paleoecology, provincialism, and stratigraphy to demonstrate various palynological methods in marine rocks. 198 Taxa were identified (76 dinoflagellate cysts, 25 acritarchs, 3 angiosperms, 15 gymnosperms, 79 spores). In addition, 3 forms of foraminiferal linings and 1 form of scolecodont were found. In the short systematic appendix, some selected taxa (3 angiosperms, 5 dinoflagellate cysts and 1 problematic microplankton) are described in detail and their systematic position discussed. For the quantitative evaluation of the palynomorph association (198 taxa!) the number of counted forms were reduced to a manageable quantity of 74 counter groups. Counter groups are defined and a differential diagnosis is given. The results of the quantitative analyses are presented as percent values in several tables. Furthermore, selected data from the quantitative analyses are summarized in two diagrams; this includes the carbonate and organic carbon content and palyno-sedimentological data ("terrigen-Index"). Quantitative data on dinoflagellate cyst associations are discussed in detail using palyno-sedimentologic data. The interpretation of such data is often difficult and altogether supplies a relatively general pattern for stratigraphic correlation. Correlation among associations from different microfloral provinces is especially difficult. In an attempt to correlate with dinoflagellate cyst associations, the quantitative data from three largely facies-independent dinoflagellate cyst taxa were compared; marked differences could perhaps allow recognition of climate-induced variations. Such regularly rhythmic variations was then used for palynological correlations in marine sediments over great distances. Additionally it was shown that quantitatively analyzed pollen-spore associations did not permit a palyno-stratigraphic correlation between both marine sections. A reconstruction of the land flora based on pollen-spore associations from the Mid-Cretaceous was hardly possible; instead some boundaries of paleo-floral subprovinces in the Mid-Cretaceous of Europe were discussed.