2009. A multi-proxy palaeoecological and palaeoclimatic record within full glacial lacustrine deposits, western Tennessee, USA.ABSTRACT: The Fulton Section, along the Mississippi River in western Tennessee, USA, is a 1 km continuous exposure ($20 m vertically) of Quaternary fluvial and lacustrine deposits, inset within Eocene sediments and buried by thick loess. Fossiliferous slackwater lake sediments record maximum aggradation during the last two major glaciations, with deposition between ca. 190-140 ka and 24-18 14 C ka BP, based on amino acid and radiocarbon chronology, respectively. During the onset of full glacial conditions (ca. 24-22 14 C ka BP), a relatively permanent shallow lake environment is indicated by ostracods, aquatic molluscs, and both pollen and macrofossils of aquatic plants. By 21.8 14 C ka BP, increasing emergent plants, amphibious gastropods (Pomatiopsis) and heavier d 18 O compositions suggest marsh-like conditions in a periodically drying lake. The surrounding uplands consisted of Picea-Pinus woodlands mixed with cool-temperate hardwoods (e.g. Quercus, Populus, Carya), grasses and herbs. More open conditions ensued ca. 20 14 C ka BP, with loess and slopewash gradually infilling the former lake by 18 14 C ka BP. Modern analogue analyses of ostracods and palaeontological evidence imply a full glacial climate similar to today's mixed-boreal zone in central Minnesota, USA, about 98C cooler in mean annual temperature than present-day western Tennessee.

The University of Wisconsin-Stevens Point was recently asked by the Arizona Museum of Natural History (AZMNH) to analyze eleven late Cretaceous sedimentary rock samples from the Fort Crittenden Formation in southeastern Arizona for fossil pollen and other palynomorphs (Table 1). The Fort Crittenden, wellknown for its Campanian faunal assemblages, outcrops in the Santa Rita Mountains near Tucson (Figure 1). In the spring of 2014, researchers affiliated with the AZMNH collected the samples from layers that harbor dinosaur and other vertebrate remains. The Fort Crittenden members are comprised of conglomerates, shales, and sandstones that are interpreted to be freshwater (fluvial and lacustrine) and subaerially-derived valley deposits. Despite ample fossiliferous faunal material and fossilized wood, little is known of the flora or the micropaleontology. To better understand the environments in which these dinosaur remains accumulated, we are using physical and chemical maceration techniques to disaggregate the rock and isolate palynomorphs. Light and scanning electron microscopy are being used for pollen identification. Experimental use of x-ray diffraction to detect cellulose presence will be tested for pollen recognition. Preliminary results show a high degree of sediment oxidation with several possible pollen and non-pollen palynomorphs that may be useful paleoenvironmental indicators. References Finkelstein, David B. et al. 2005. "Wildfires and seasonal aridity recorded in Late Cretaceous strata from southeastern Arizona, USA". Sedimentology.

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