<p>This thesis documents the development and application of a unique database orientated software package, BugsCEP, for environmental and climatic reconstruction from fossil beetle (Coleoptera) assemblages. The software tools are described, and the incorporated statistical methods discussed and evaluated with respect to both published modern and fossil data, as well as the author’s own investigations.</p><p>BugsCEP consists of a reference database of ecology and distribution data for over 5 800 taxa, and includes temperature tolerance data for 436 species. It also contains abundance and summary data for almost 700 sites - the majority of the known Quaternary fossil coleopteran record of Europe. Sample based dating evidence is stored for a large number of these sites, and the data are supported by a bibliography of over 3 300 sources. Through the use of built in statistical methods, employing a specially developed habitat classification system (Bugs EcoCodes), semi-quantitative environmental reconstructions can be undertaken, and output graphically, to aid in the interpretation of sites. A number of built in searching and reporting functions also increase the efficiency with which analyses can be undertaken, including the facility to list the fossil record of species found by searching the ecology and distribution data. The existing Mutual Climatic Range (MCR) climate reconstruction method is implemented and improved upon in BugsCEP, as BugsMCR, which includes predictive modelling and the output of graphs and climate space maps.</p><p>The evaluation of the software demonstrates good performance when compared to existing interpretations. The standardization method employed in habitat reconstructions, designed to enable the inter-comparison of samples and sites without the interference of differing numbers of species and individuals, also appears to be robust and effective. Quantitative climate reconstructions can be easily undertaken from within the software, as well as an amount of predictive modelling. The use of jackknifing variants as an aid to the interpretation of climate reconstructions is discussed, and suggested as a potential indicator of reliability. The combination of the BugStats statistical system with an enhanced MCR facility could be extremely useful in increasing our understanding of not only past environmental and climate change, but also the biogeography and ecology of insect populations in general.</p><p>BugsCEP is the only available software package integrating modern and fossil coleopteran data, and the included reconstruction and analysis tools provide a powerful resource for research and teaching in palaeo-environmental science. The use of modern reference data also makes the package potentially useful in the study of present day insect faunas, and the effects of climate and environmental change on their distributions. The reconstruction methods could thus be inverted, and used as predictive tools in the study of biodiversity and the implications of sustainable development policies on present day habitats.</p><p>BugsCEP can be downloaded from http://www.bugscep.com</p>

In the Kisumu District, Kenya, unreliable rainfall pattern has been identified as one of the main causes for poverty in rural areas. The negative effects of such unreliable patterns could be mitigated through improved water resource management and planning. However, estimates of current (and future) water availability will likely differ depending on whether managers draw upon data gathered at a local-scale or regional-scale. This is particularly important in developing regions where, due to lack of data availability, managers are often limited in their choice of data resolution. This study investigates the potential effect of spatial resolution of data on water management and planning by comparing hydro-climatic trends in local-scale data with trends in regional-scale data. The influence of adopting local-scale versus regional-scale data is further demonstrated by estimate the storage requirements of proposed irrigation ponds for farmers in the Orongo village of the Kisumu District located in Kenya, Africa. Results indicate a low correlation between local and regional hydro-climatic trends. Data spatial scale directly influences water resources management leading to a 300% difference in estimated storage requirement for the average farmer.

Recent work suggests an emerging new paradigm for the Scandinavian ice sheet (SIS); one of a dynamically fluctuating ice sheet. This doctoral research project explicitly examines the history and dynamics of the SIS at four sites within Sweden and Norway, and provides results covering different time periods of glacial history. Two relatively new dating techniques are used to constrain the ice sheet history: the optically stimulated luminescence (OSL) dating technique and the terrestrial cosmogenic nuclide (TCN) exposure dating technique. OSL dating of interstadial sediments in central Sweden and central Norway indicate ice-free conditions during times when it was previously inferred the sites were occupied by the SIS. Specifically, the SIS was absent or restricted to the mountains for at least part of Marine Isotope Stage 3 around 52 to 36 kyr ago. Inland portions of Norway were ice-free during part of the Last Glacial Maximum around 25 to 20 kyr ago. Consistent TCN exposure ages of boulders from the Vimmerby moraine in southern Sweden, and their compatibility with previous estimates for the timing of deglaciation based on radiocarbon dating and varve chronology, indicate that the southern margin of the SIS was at the Vimmerby moraine ~14 kyr ago. In central Sweden, consistent TCN ages for boulders on the summit of Mt. Åreskutan and for the earlier deglaciated highest elevation moraine related to the SIS in Sweden agree with previous estimates for the timing of deglaciation around 10 ka ago. These results indicate rapid decay of the SIS during deglaciation. Unusually old radiocarbon ages of tree remains previously studied from Mt. Åreskutan are rejected on the basis of incompatibility with consistent TCN ages for deglaciation, and incompatibility with established paleoecological and paleoglaciological reconstructions. Altogether this research conducted in different areas, covering different time periods, and using comparative geochronological methods demonstrates that the SIS was highly dynamic and sensitive to environmental change. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Manuscript.

Manito Lake is a large, perennial, Na-SO4 dominated hypersaline lake located in the northern Great Plains of western Canada. Significant water level decrease over the past several decades has lead to reduction in volume and surface area. Today, the lake is 15% of its mid -20th century volume and 46% of its former area. This decrease in water level has exposed large areas of nearshore microbialites. These organosedimentary structures have various external morphologies, vary in mineralogical composition, and show a variety of internal fabrics from finely laminated to massive and clotted. These features range from small, mm-scale, finely laminated encrustations to large, reef-like structures up to 5 m high and over 500 m long. Although there is relatively little consistent lateral variability in terms of morphology, the structures do vary significantly with elevation in the basin. Petrographic evidence confirms a strong biological involvement in the formation of these structures. Nonetheless, inorganic and trapping mechanisms may also play a role. Dolomite, aragonite, and calcite are the most commonly found minerals in these structures, however, monohydrocalcite, magnesian calcite, hydromagnesite, dypingite, and nesquehonite are also present. The calcite is a pseudomorph after ikaite, which forms an open porous dendritic and shrub-like fabric, comprising the interiors of massive shoreline microbialite mounds and pinnacles. These ikaite pseudomorphs are encased in millimeter to centimeter-scale laminated dolomite-aragonite rinds. Radiocarbon dating and stable isotope analysis have indicated microbialite formation began about 2200 yBP in a shallow, productive, saline and cold lake. Over the next 900 years, the microbialites record a transgressing lake in a cool climate, which corresponds to a period not previously documented in this region but is referred to as the Dark Ages Cold Period, which has been documented in other parts of the Northern Hemisphere. This is followed by 500 years of warmer conditions coinciding with the Medieval Climate Anomaly. Starting about 600 years ago the lake experienced a dramatic decrease in level resulting in formation of extensive carbonate pavements, cemented siliciclastics, rinds, and coatings.

Manito Lake is a large, perennial, Na-SO4 dominated hypersaline lake located in the northern Great Plains of western Canada. Significant water level decrease over the past several decades has lead to reduction in volume and surface area. Today, the lake is 15% of its mid -20th century volume and 46% of its former area. This decrease in water level has exposed large areas of nearshore microbialites. These organosedimentary structures have various external morphologies, vary in mineralogical composition, and show a variety of internal fabrics from finely laminated to massive and clotted. These features range from small, mm-scale, finely laminated encrustations to large, reef-like structures up to 5 m high and over 500 m long. Although there is relatively little consistent lateral variability in terms of morphology, the structures do vary significantly with elevation in the basin. Petrographic evidence confirms a strong biological involvement in the formation of these structures. Nonetheless, inorganic and trapping mechanisms may also play a role. Dolomite, aragonite, and calcite are the most commonly found minerals in these structures, however, monohydrocalcite, magnesian calcite, hydromagnesite, dypingite, and nesquehonite are also present. The calcite is a pseudomorph after ikaite, which forms an open porous dendritic and shrub-like fabric, comprising the interiors of massive shoreline microbialite mounds and pinnacles. These ikaite pseudomorphs are encased in millimeter to centimeter-scale laminated dolomite-aragonite rinds. Radiocarbon dating and stable isotope analysis have indicated microbialite formation began about 2200 yBP in a shallow, productive, saline and cold lake. Over the next 900 years, the microbialites record a transgressing lake in a cool climate, which corresponds to a period not previously documented in this region but is referred to as the Dark Ages Cold Period, which has been documented in other parts of the Northern Hemisphere. This is followed by 500 years of warmer conditions coinciding with the Medieval Climate Anomaly. Starting about 600 years ago the lake experienced a dramatic decrease in level resulting in formation of extensive carbonate pavements, cemented siliciclastics, rinds, and coatings.

It is important to study subglacial environments in northern Canada for many reasons, such as to develop a more comprehensive understanding of glacial landscape development and to aid in mineral exploration. The purpose of this research is improve understanding of the Quaternary Geology of north central Hall Peninsula, Baffin Island, the subglacial dynamics record in particular, in order to provide industry with new knowledge, maps and interpretations to aid in mineral exploration. The glacial history of north-central Hall Peninsula, Baffin Island is very complex. By studying the subglacial landscape using both remote- and field- based techniques it was possible to develop a subglacial landscape map and a flowset map which highlighted areas with different glacial histories and basal thermal regimes. The subglacial dynamics and how they changed spatially and temporally shaped the landscape to what it is today with a mixture of cold, intermediate, and warm-based ice. Through mapping using remote sensing and field methods, seven glacial landform and striation directions were found and grouped into four ice flow events. The identified ice flows include regional flows, northern and eastern fjord influenced areas, central deglacial flows, and modern icecap flows. Subglacial erosion was investigated using several proxies including streamlined hill elongation ratios, streamlined hill density, and bedrock controlled lake density studies. These proxies together with the subglacial landscape map were overlaid to select discrete zones, termed glacial terrain zones (GTZs), in an attempt to analyze the subglacial dynamics and how different basal thermal regimes interacted with the landscape. Five glacial terrain zones (GTZs) were identified, with different spatio-temporal basal ice regimes and landform assemblages. The first zone (GTZ 1) is characterized by an expansive flowset of parallel paleo-flow indicators trending northeast. This zone has the highest degree of areal scour with thin, discontinuous and relatively unweathered till. The second zone, GTZ 2, is an area where the broad northeast flowset is crosscut locally by ice flow indicators that converge into troughs that now form a series of north trending fjords in the north of the study area. This overprinted landscape is found to propagate inland forming a channelized system, leading way to linear erosion. The modern icecap resides in GTZ 3, which inherited the broad northeast flowset, but is overprinted in valleys by eastern flows funneling into the fjords to the east, as well as western flows flowing from the modern icecap. In the central area, there is a rolling terrain of thicker till (GTZ 4) that is distinguished by its lack of subglacial features. The final contrasting landscape (GTZ 5) is characterized by southeast trending bedrock features (most likely enhanced by southeast flowing ice) and associated perpendicular moraines. GTZ 5 is also characterized by highly weathered bedrock, and locally by landform assemblages recording late deglacial readvances of thin lobes including moraines and striated outcrops. Geochemical studies for each of these landscapes lead to additional insights, characterizing the five zones further. The geochemical studies took advantage of two till sample databases taken over the study area for exploration purposes by Peregrine Diamonds LTD. The chemical index of alteration (CIA) was applied to compare erosion in the different zones. High CIA values indicate high weathering, where low CIA values low weathering. GTZ 1 is characterized by low CIA values (low weathering footprint), and GTZ 5 is characterized by high CIA value (highly weathered). To study if the GTZs had a distinct geochemical signature, as well as a signature landscape, multivariate geochemical statistics (Principal Component Analysis and Linear Discriminant Analysis) were done over the study area. Interestingly, it was found that the GTZs have geochemical signatures, which reflect the role of underlying bedrock, weathering patterns, glacial dispersal, and the complex relationships between subglacial dynamics and landscape evolution. To determine if the GTZs could be predicted by the till geochemistry, linear discriminant analysis was subsequently applied. The results indicate that the till geochemical data has a predictive capacity with an accuracy of 83.78%, which brings insight into the relationship between glacial landscapes and till composition. With this multi-proxy approach and building from previous studies, a conceptual model was developed for the study area. During the Last Glacial Maximum (LGM), the study area was inundated by the Laurentide Ice Sheet (LIS), with the Hall Ice Divide parallel to the axis of the peninsula with ice flowing from the divide to the northeast and southwest. As ice thinned, GTZ 1, an area once inundated with warm-based ice, as shown by evidence of areal scour and low CIA values, switched to being cold-based ice preserving an older landscape. Though GTZ 1 was under cold-based ice, warm-based conditions still prevailed within the channelized flow zones, which characterize GTZ 2. Evidence of this is found in the striation record, as well as the low CIA value indicative of low weathering (or high erosion). This may reflect a transition from LGM (thick-based ice) to thinner, topographically controlled ice, with cold-based ice in interfluves and hilltops, during early deglaciation. The catchment zones of the channelized system locally extend near the central area (GTZ 4) which is reflected in dispersal patterns and the striation record. As the LIS retreated, it went through a series of southeastward readvances and surges (GTZ 5). Though the ice was warm-based near the moraines in GTZ 5, prevailing cold-based conditions prevailed during most of the last glacial cycle, and the late deglacial readvances had limited erosion capacity and did not overprint the cold-based landscape significantly. This is shown by the CIA values indicative of high weathering, and lack of subglacial landforms. Series of pro-glacial lakes also formed in front of the retreating lobe. Ice is needed over GTZ 1 to prevent these lakes from draining northward. This thin ice was most likely cold-based, preserving the older GTZ 1 landscape of areal scouring. The glacial landscape of Hall Peninsula appears to record a switch from uniform warm-based LGM ice, which was laterally extensive, to localized channel flows in the fjords during deglaciation and intervening cold-based ice. The change in the geometry and basal thermo-mechanical conditions may be the prologue to the separation of the modern day ice cap from the LIS.

This study involved a regional hydrogeological assessment of the Comox Coalfield on Vancouver Island, British Columbia. Two site-specific geological and hydrogeological investigations were conducted. The first involved generating a 2.5 dimensional hydrostratigraphic model of part of the Quadra Sand Comox-Merville Aquifer using lithology information from 196 drilled domestic-use groundwater wells. Well logs were standardized with respect to lithologic and hydraulic characteristics. Contact surfaces were created for identifiable hydrostratigraphic units employing an iterative geostatistical interpolation process that incorporated contact points from well logs and interpreted points based on the regional hydrogeology. Modeled hydrostratigraphic surfaces were compared to logged contacts and to exposures at Willemar and Lazo bluffs at Comox. Six lithostratigraphic units were identified in the coastal exposures. Hydraulic conductivity values, estimated from grain size data using the Hazen method, for the lowermost 4 units were: 2.3 x 10-3 cm/s, 9.1 x 10-6 cm/s, 9.4 x 10-3 cm/s, and 4.7 x 10-6 cm/s, respectively. The hydrostratigraphic model was verified using statistical variance analysis, field reconnaissance data, and the identification of a separate surficial aquifer within the study area. The model identified all units mapped in the field and two units below sea level, inferred to be the Cowichan Head Formation. The Comox Bluff model successfully predicted, within 2 m vertically, subsurface hydrostratigraphic boundaries 80% of the time. The second component of the study included a hydrogeological investigation of stacked Quaternary and Late Cretaceous bedrock aquifers at Oyster River. This investigation incorporated drilling logs, borehole geophysics, aqueous geochemistry, pumping and recovery test data, and hydrostratigraphic interpretation of surficial exposures. The potential for hydraulic communication between the Late Cretaceous Nanaimo Group fractured sedimentary bedrock and the overlying unconsolidated Quaternary aquifers was examined. Two adjacent groundwater observation wells were drilled; one completed in bedrock (146.9 m) and one in the surficial sediments (7.3 m). The deeper well penetrated the Trent River and Comox Formations of the Nanaimo Group. A water-bearing fracture zone approximately 3 m wide was encountered at 135 metres below ground surface, coincident with the Comox Y and Y Lower coal seams. Dissolved methane gas was detected in the bedrock aquifer, with an initial concentration of 2,123 mg/L. Schoeller diagrams reveal that the gas in bedrock is coal related. A pumping and recovery test in the deep well suggests that there is unlikely any hydraulic communication between the bedrock and surficial aquifers encountered at Oyster River. This assessment is based on infrequent water level measurements in the shallow well, which did not consistently draw down during pumping of the deeper well. However, the pumping rate was not sustainable for this test and it could not be held constant. Fracture transmissivity and hydraulic conductivity for the bedrock aquifer were estimated using the Theis Recovery method at 7.06 x 10-7 m2/s and 2.29 x 10-7 m/s, respectively. The hydrogeological research conducted at Comox and Oyster River highlights the effectiveness of a multidisciplinary approach for subsurface investigations. This study contributes site level data upon which regional inferences can be built for the Comox Coalfield.

No description available.

Análise de depósitos sedimentares quaternários da Região Amazônica é de grande interesse para a reconstituição da dinâmica de evolução de sua bacia de drenagem, bem como para subsidiar discussões relacionadas com paleoclima, nível do mar e tectônica. Existem, ainda, poucos estudos dedicados a este tipo de abordagem, o que se deve, principalmente, à ausência de exposições naturais devido à baixa topografia da área. Este trabalho integra análise de fácies, datação radiogênica, e análise de 13C, 15N e C/N de um testemunho de 124 m de espessura, obtido próximo ao Lago Arari, nordeste da Ilha do Marajó, Estado do Pará. Os sedimentos estudados foram depositados nos últimos 50 ka, e registram os seguintes ambientes deposicionais: canal fluvial, representado por areia maciça fina a grossa, localmente conglomerática, moderadamente selecionada e, subordinadamente, argilas laminadas plano-paralelas, arranjados em vários ciclos granodecrescente ascendentes com espessuras de até 8 m; bacia estuarina externa a marinho raso, consiste principalmente em argila com laminação paralela a streaky, intercalada com camadas heterolíticas lenticular e wavy/flaser, formando sucessões granocrescente ascendentes; bacia estuarina proximal, litofaciologicamente similar aos depósitos de bacia estuarina externa, tendo espessura menor (até 10 m), com estratos arranjados em ciclos granocrescente e granodecrescente ascendentes; planície de maré, formada por camadas heterolíticas dos tipos lenticular e wavy/flaser, o localmente interacamadadas com pacotes de areia maciça de até 1 m de espessura, formando ciclos granodecrescentes ascendentes de até 4 m de espessura; canal estuarino, formado por sucessão com cerca de 15 m de espessura, constituída de areias finas a grossas e, secundariamente, depósitos heterolíticos, arranjados em ciclos com adelgaçamento e granodecrescência ascendentes; e laguna, representada dominantemente por argila com laminação paralela a streaky, intercalada a pacotes heterolíticos de até 3 m de espessura, formando ciclos granodecrescente e granocrescente ascendentes. A interpretação faciológica foi complementada por análises de 13C, 15N e C/N, obtidas a partir da matéria orgânica dos sedimentos. Os valores confirmam ambiente com contribuição de diferentes fontes de matéria orgânica, como esperado em ambientes costeiros estuarinos e deltaicos sujeitos a fontes de matéria orgânica alóctones (fitoplâncton marinho, mais comumente trazidos por correntes de maré) e autóctones (fitoplâncton de água doce e matéria orgânica terrígena). Análises palinológicas foram realizadas em 108 amostras síltico-argilosas, que foram selecionadas com base em variações faciológicas. Os dados obtidos revelaram baixas concentrações de palinomorfos e frequência descontínua ao longo do testemunho estudado. Dois intervalos estratigráficos foram mais ricos em material palinológico. O primeiro compreende os 18 m superficiais do testemunho, sendo correspondente a depósitos lagunares, os quais registraram idade de até 10.000 AP. Neste intervalo, a taxa de concentração de polens calculada variou de 3.539,6 a 13.124,2 grãos/cm3. O tipo polínico dominante é a Rhizophora (20,8%-45,0%), elemento índice de manguezais. Outros arbóreos identificados incluem Alchornea (1-7,8%), Anacardiaceae (0- 6%), Euphorbiaciae (0-4,9%), Fabaceae (1-8,2%), Mauritia (0-4%), Melastomataceae (0,8-9,8%), Moraceae/Urticaceae (0-5%), Rubiaceae (0-6%). Vegetação herbácea inclui espécies de Amaranthaceae/Chenopodiaceae (0-4%), Cyperaceae (1-20%) e Poaceae (1,3-11%). O segundo intervalo localiza-se entre 77 e 93 m de profundidade e corresponde a sedimentos de ambiente de bacia estuarina proximal, de idade basal calculada em 50.795± 5.090 AP. A concentração varia de 9.095,5 a 22.688,5 grãos/ cm3. Polens herbáceos apresentam maiores concentrações (1.330,0-7.911,6 grãos/ cm3) do que no primeiro intervalo e, dentre este grupo, predominam os elementos de Poaceae (9- 26,5%). Entre os tipos arbóreos, as maiores frequências foram de Alchornea (0-6%), Celtis (0-7,1%), Euphorbiaceae (0-8%), Fabaceae I (tipo psilado) (1-14%), Ilex (0- 4,1%), Mauritia (1-10,7%), Malpigiaceae (0 7,1%), Melastomataceae/Combretaceae (1-10%) e Rubiaceae (0-7%). A análise da arquitetura estratal dos depósitos pleistocênicos tardios e holocênicos da região do Lago Arari revela que a sedimentação aconteceu dominantemente sob condições estuarinas, desenvolvolvidas ao longo de episódios de transgressão e regressão, como indicado pela natureza cíclica dos depósitos. Deposição fluvial ocorreu entre 40.950 (±590) e 50.795 14C AP, seguido de episódio de elevação do nível relativo do mar (NRM) iniciado entre 35.567 (±649) e 39.079 (±1.114) 14C AP. Ampla transgressão ocorreu até 29.340 (±340) 14C AP, indicado pelos depósitos de bacia estuarina externa a marinho raso, seguido de fase de declínio do NRM, que favoreceu rejuvenescimento e incisão do vale. Nova fase de elevação do NRM ocorreu por volta de 10.479 (±34) 14C AP, a qual culminou com o preenchimento do vale por depósitos estuarinos. O influxo fluvial foi interrompido em torno de 10.479 (±34) 14C AP, como resultado da evolução do estuário, provavelmente para uma laguna. O declínio do NRM aconteceu no final do Holoceno, que resultou em progradação costeira em direção a norte, processo este que teria culminado com a evolução da laguna para o sistema lacustre do Lago Arari atual. Apesar da influência de flutuações eustáticas, o contexto geológico permite sugerir que a tectônica regional desempenhou papel importante na criação de espaço acomodacional para a deposição dos sedimentos pleistocênicos-holocênicos da área do entorno do Lago Arari. / Analysis of Quaternary sediments in Amazonia is of great interest for reconstructing the dynamic evolution of its drainage basin, and to support discussions related to paleoclimate, sea level and tectonics. Few studies emphasize this type of approach, which is mainly due to lack of natural exposures due to the low topography of the area. This work integrates facies analysis, radiogenic dating, 13C, 15N and C/N analyses of an 124 m-thick obtained in the area located near Lake Arari, northeastern Marajó Island, State of Pará. The studied sediments were deposited in the last 50 ka, and record the following depositional environments: fluvial channel, represented by massive, moderately sorted, fine- to coarse-grained, locally conglomeratic, sand, and subordinate mud with parallel lamination, which are arranged in several fining upward cycles up to 8 m thick; outer estuarine basin to shallow marine, mainly consisting of mud with parallel to streaky lamination, interbedded with lenticular and wavy/flaser heterolithic layers, forming a coarsening upward succession; inner estuarine basin, lithologically similar to the outer estuarine basin to shallow marine deposits, with smaller thickness (up to 10 m), and with layers arranged in coarsening and fining upward cycles; tidal flat, formed by lenticular and wavy/flaser heterolithic layers, which are locally interbedded with massive sand packages up to 1 m thick, forming finning upward cycles up to 4 m thick; estuarine channel, formed by a succession about 15 m thick, consisting of fine to coarse-grained sand and, secondarily, heterolithic deposits, which are arranged in both

<p>In this thesis the Weichselian history of northern Sweden is investigated, with emphasis on vegetation and climate during ice-free intervals. The main method used has been pollen analysis of sediments from pre-Late Weichselian landforms. To interpret fossil pollen assemblages, comparisons with modern pollen spectra were made. Modern pollen data were retrieved through monitoring of annual pollen deposition at seven sites in northern Sweden, from the boreal forest to above the present forest-line of birch. Eight years of pollen monitoring is described and put in a larger context through comparison with monitoring data from Iceland, Svalbard, Norway and Finland. A study of sediment cores from the Riipiharju esker shows evidence of two ice free phases during the Weichselian glacial; Tärendö I and Tärendö II. The Tärendö II ice free interval includes large climatic shifts, previously not recognized, from relatively warm conditions with <i>Betula</i> as the dominating pollen taxon to cold conditions with dominance of <i>Artemisia</i> and Gramineae and back to warmer conditions again. Correlation alternatives of the north Swedish ice free intervals Tärendö I and II are: 1/ Brörup (MIS 5c; c. 105-93 ka BP) and Odderade (MIS 5a; c. 85-74 ka BP), respectively, or 2/ Odderade and early Middle Weichselian time (MIS 3; c. 59-40 ka BP). Of these, alternative 2 is regarded as the most likely. Interstadial sediments deposited in a Veiki moraine plateau during downwasting of a pre-Late Weichselian ice sheet include only <i>Betula</i> dominant pollen spectra, showing that the climate during formation of the Veiki moraine was relatively warm. According to stratigraphical correlation there are three possible alternatives for Veiki moraine formation. Either it was formed during 1/ early Tärendö I, 2/ early Tärendö II, or 3/ late Tärendö II. Alternative 3 implies growth of an intermediate ice sheet reaching the eastern limit of Veiki moraine distribution during the cold phase of Tärendö II.</p>