received much attention as a possible analogue for the future. At the beginning of this period, the Greater Yellowstone Ecosystem (GYE) sup- ported the largest mountain glacier complex in the western US, and ice recession after 17,000 years ago put into motion a series of biologic changes that resulted in the present-day terrestrial ecosystem. Pollen and plant macrofossil records from a series of sites in the northern GYE (Dailey Lake, Blacktail Pond, Slough Creek Pond, and Abundance Lake) record a sequence of postglacial vegetation changes, starting with an initial period of tundra vegetation with birch, aspen, and juniper and followed by a parkland of spruce, whitebark pine, and subalpine fir; then a closed subalpine forest, and finally an open forest of Douglas-fir and lodgepole pine. These plant communities and their temporal succession are similar to what can be found along a high-to-low elevational gradient in the GYE at present. The different sequence of postglacial conifer arrivals from one site to the next suggests a strong influence of nonclimatic controls. The general dispersal patterns and rate of spread for conifer species in the region is comparable to that found in other parts of North America. The interesting question for the future is whether past rates of migration will be adequate for species to maintain equilibrium with projected changes in climate. PALAEODEMOGRAPHY OF THE MAGDALENIAN - ESTIMATING POPULATION DENSITY OF HUNTER-GATHERER DURING THE LATE UPPER PALAEOLITHIC IN EUROPE Inga Kretschmer. University of Cologne, Germany E-mail address: ingakretschmer@aol.com The PhD-Project “Analysis of the Palaeodemography of hunters and gatherers of the Late Upper Palaeolithic in Europe” is part of the Collabo- rative Research Centre 806 “Our way to Europe“ funded by the German Research Foundation and investigates the demography of the Late Upper Palaeolithic hunter-gatherer populations, when Europe was repopulated after the Last Glacial Maximum. The aim is to develop a method for esti- mating regional differentiated population densities and to determine varying settlement patterns. A method based on GIS techniques is used to upscale archaeological data from key sites and regions to culturally homogenous contextual areas in Europe. Based on spatial density of Late Upper Palaeolithic sites, GIS- calculated regions are interpreted as indicators for settlement areas at the largest scale. The origin of raw materials from key sites indicates seasonal or annual territories used by a group of humans at an intermediate scale. Size relation of settlement area and raw material catchment is an indica- tion for the number of hunter-gatherers in a region. These results will be related to compatible group sizes observed in ethnographic data. Such concepts are compared with settlement sizes and patterns from well- excavated key sites in the different regions. Investigation of population density and settlement patterns will help to identify differences and similarities of mobility and demographical processes in distinct regions of Europe. EXTENT OF THE LATE GLACIAL LAKE ROSENHEIM AND IMPLICATIONS OF ISOSTATIC MOVEMENTS (SOUTHERN GERMANY, UPPER BAVARIA) Ernst Kroemer. Bavarian Environment Agency, Germany E-mail address: ernst.kroemer@lfu.bayern.de In 2010 the area of sheet No. 8138 Rosenheim was geologically mapped by the Geological Survey of the Bavarian Environment Agency. Base for interpretation was a digital surface model (2 m resolution, Bayerische Vermessungsverwaltung). More than 1100 borings with hand auger equipment (Eijkelkamp model P1.04.03) were made. The mapped area is situated in the central part of the former Lake Rosenheim and so it was necessary to look at the shoreline of the lake. With more than 450 km 2 former Lake Rosenheim was the second largest lake after Lake Konstance in the northern alpine piedmont. It was built during retreat of the Inn glacier, which left a basin with a maximum depth of 300 to 350 m corresponding to a water level of around 480 m NN. During the Late Glacial the lake was filled up with silty sediments up to a level of about 460 m NN. On the northern end of the lake a barrier was eroded clearly before 10 210 + 210 y BP [H – 409/ 374] (Wolff 1973) and the lake drained off. The age was taken from driftwood which was found in the second oldest river terrace in the Rosenheim basin. The interpretation of the shoreline and relics of deltas show a lake level in the northern part near Edling around 478 to 480 m NN. In the southern part near Flintsbach deltaic sediments point to a lake level at 488 m NN. This presents the first implication of isostatic movements of 10 meters on a distance of 37 km in the eastern alpine foreland of Bavaria. PALAEOSURFACE ANALYSIS ON THE PARANÁ CRETACEOUS BASALTIC PLATEAU (SE SOUTH AMERICA) Daniela M. Kröhling. CONICET - Fac. Ing. y Cs. Hídricas (Universidad Na, Argentina E-mail address: dkrohli@gmail.com SRTM data constituted a good resource for morphometrical analyses of the K-basaltic plateau. Palaeosurface remnants of the Upper Río Uruguay basin preserve attributes that have been identified in digital elevation models. Generation of hypsometric curves in five tributary basins of the Uruguay basin and also in one basin tributary of the Río Paraná permitted to identify, classify and map the main Cenozoic palaeosurfaces of the plateau. Other morphometric parameters such as longitudinal profiles and isobase lines were produced also to delimit such surfaces. Stepped systems of planation surfaces as a result of cyclic evolution related to the regional uplift induced by break-up of the Gondwana were early investigated by King in southern Brazil. This research was extended on the Paraná and Uruguay rivers watershed in order to identify palaeosurface remnants and to correlate them to those described previously. Palaeosurfaces 1 and 1b are equivalent to King's Sul-American Pediplain. Both surfaces 1 and 1b (> 883 m a.s.l.) are well represented in the Río Pelotas basin (Brazil). If the Upper Río Uruguay basin corresponded to the lower segment of the palaeosurface, a predicted base level value would be estimated around 840 m a.s.l. The higher remnant surface of the plateau of NE Argentina is interpreted as Palaeosurface 2b (676-883 m a.s.l.). King's Velhas Surface (Upper Tertiary-Lower Quaternary) is correlated with Palaeosurface 2, which in Misiones comprises the plane-top watershed between the Paraná and Uruguay basins (436- 676 m a.s.l.). This surface is widespread in the Upper Río Uruguay basin, represented by a landscape of gentle and rounded hills. The lower surfaces 3 and 4 correspond to the Apóstoles Pediplain (200 m a.s.l.), which would be generated by King’s Paraguaçú cycle (Pleistocene), represented by valley incision. BEDROCK CHANNEL MORPHOLOGY OF THE UPPER URUGUAY RIVER (SOUTH AMERICA). BATHYMETRIC SONAR DATA OF THE INNER CANYON Daniela M. Kröhling. CONICET - Fac. Ing. y Cs. Hídricas (Universidad Na, Argentina E-mail address: dkrohli@gmail.com The upper Uruguay River is developed on the K-basaltic plateau of S Brazil and NE Argentina. The bedrock channel morphology is dominated by erosional processes, reflecting the spatial variability in hydraulics along the channel. Variations in channel width, depth and gradient produces differences in flow energy generated longitudinal grooves, knickpoints, inner channel, rapids and step-pools. At the largest scale, tectonic features and patterns of stream power dominate the erosive channel morphology. A persistent characteristic of the Uruguay bedrock is the narrow and sinuous, deep inner channel (canyon). It was detected along the Argentina-Brazil border and it is continuous and permanently submerged, except in a segment of ca. 3 km. There the river crosses an elevated tectonic block producing the emergence of the deep canyon (50 m width). It forms the Moconá, a system of longitudinal waterfalls of 10-12 m high in normal periods. A boat-based survey of the incised channel was made in a continuous segment of 55 km between the mouth of the Yabotí River and El Soberbio (Misiones province), using the Phase Measurement Bathy- metric Sonar System. Digital maps (1 m gridded with decimeter vertical precision) were generated. The results revealed the 3D nature of the canyon; en general it occupies 1/3 to 1/10 of the channel width and it is incised between 6 to 22 m in the plane-bedrock channel (2 to 3 m depth). In segments of 1.5 to 4 km, the canyon depths are in the range of 24 to 32 m, 50 to 100 m wide. The section is well delineated with 40 to 80  flanks Abstracts / Quaternary International 279-280 (2012) 233–345 256