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Zufolge einer vorl~iufigen Auswertung palynologiseher Information tiber ladinisehe und besonders karnisehe Schichtfolgen, scheint es deutliche Anzeichen zu geben, dab qualitative und quantitative Unterschiede in der Zusammensetzung palynologischer Assoziationen gut angewandt werden kSnnten beim Testen der Konzepte yon triassischer Phytogeografie und Pal~ioklimatologie.Untenstehende Implikationen werden betont:(1) Es gibt gentigend palynologischen Beweis, dab das Mittelmeergebiet auch einen Bereich enth~ilt, der von gemischten, nSrdlichen (laurasischen) und siidlichen (gondwanisehen) Floratypen charakterisiert ist.(2) Das Konzept einer wesentlich ariden Natur einer breiten ~iquatorialen Zone w~ih-w~ihrend der Trias wird durch palynologische Forschung untersttitzt.(8) Palynologische Daten wiedersprechen nicht dem Konzept, dab es eine ausgesprochene Abnahme yon Niederschlag in westliche Richtung des Mittelmeergebiets gab.(4) In Europa kann die Anwesenheit von hygrophytischen Palynofloren und Kohlen in einer ariden klimatischen Zone erkl~irt werden durch die Wasserzufuhr yon extensiven Flul3systemen. AbstractFollowing a tentative evaluation of palynological information from Ladinian and, more particularly, Karnian successions, there seems to be every indication that qualitative and quantitative compositional differences of palynological assemblages could well be applied in testing concepts of Triassic phytogeography and palaeoclimatology.The following implications are emphasized:(1) There is sufficient palynological evidence that the Mediterranean region includes a domain of mixed northern (Laurasian) and southern (Gondwana) types of floras.(2) The concept of an essentially arid nature of a wide equatorial climatic belt during Triassic times finds palynologieal support.(8) Palynologieal evidence does not contradict a concept of pronounced decrease in precipitation towards the western part of the Mediterranean region.(4) In Europe, occurrences of hygrophytie palynofloras and coals within an arid climatic zone can be explained by the water-supply of extensive river-systems. R6sum6Suivant un essai d'6valuation des indications palynologiques reeueillies dans les s6ries du Ladinien et plus particuli6rement du Karnien, il semble qu'il y air certaines indications pour que des diff6rences qualitatives et quantitatives dans les assemblages palynologiques Les conclusions suivantes sont soulign6es:(1) I1 y a suffisamment de t6moignage palynologique indiquant que la r6gion m6di-terran6enne renferme un domaine avec un m61ange de types de flores septentrionales (laurasiennes) et m6ridionales (gondwaniennes).(2) L'id6e d'une nature essentiellernent aride form6e d'une large ceinture climatique 6quatoriale pendant les temps triasiques trouve un soutien palynologique.(8) Le t6moignage palynologique ne conteste pas la conception d'une diminution manifeste des pr6cipitations vers la partie occidentale de la r6gion m6diterran6enne.(4) En Europe, la pr6sence de palynoflores hygrophitiques et de charbons dans une zone climatique aride peut...

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Geochemical studies on Upper Carboniferous marine bands showed that marked enrichment in redox-sensitive trace elements (uranium (U), vanadium (V), molybdenum (Mo)) mostly occur if they contain Goniatites. Goniatites indicate deposition in relatively distal and deep marine environments. In contrast, Westphalian marine bands found in the Netherlands predominantly show a Lingula facies, indicating deposition in a nearshore environment. These Lingula marine bands are mostly lacking significant trace element enrichments. The aim of this paper is to explain the mechanisms causing the differences in geochemical characteristics between distal (Goniatites facies) and proximal (Lingula facies) marine bands. Geochemical analyses (total organic carbon (TOC), sulfur (S), major and trace elements) were carried out on a selection of these marine bands. Furthermore, a comparison was made with some lacustrine bands which broadly show the same sedimentary development as the Lingula marine bands. The results show that the Lingula marine bands, in contrast to the Goniatites and lacustrine bands, are characterised by low organic carbon contents (1 – 2 wt.%). A relatively high input of siliciclastics probably prevented the accumulation of organic-rich layers (dilution effect). In turn, low organic carbon contents most likely prevented the effective scavenging of trace elements. Although the lacustrine bands are characterised by high TOC contents, here the limited availability of trace elements in fresh water forms the best explanation for low trace metal enrichments. Since marine bands form stratigraphically important horizons in the Upper Carboniferous, many attempts have been made to recognise marine bands using well logs (gamma-ray). The results from this study show that using gamma-ray devices (detecting U-enrichments), only marine bands in a Goniatites facies are clearly recognised while Lingula marine bands are not detected.

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