depression, approximately modern precipitation would have been neces- sary to support LGM glaciation in Colorado, significantly less than modern precipitation to the north in Wyoming, and almost twice modern precip- itation to the west in Utah and the south in New Mexico. The west-to-east (Utah-to-Colorado) LGM moisture gradient is consistent with precipitation enhancement from pluvial Lake Bonneville, decreasing with distance downwind from the lake. The north-to-south (Wyoming-to-New Mexico) gradient is consistent with a southward LGM displacement of the mean winter storm track associated with the position of the Pacific Jet Stream. Ongoing work is investigating the effects of changing precipitation sea- sonality on paleoglacier mass balances. RESOLVING THE DEPOSITION PATTERN OF THE DEAD SEA LAMINAE AND ITS IMPLICATION FOR UNDERSTANDING HYDRO-CLIMATIC SHORT-TERM VARIATIONS IN THE LEVANT Suzanne Leroy. Institute for the Environment, Brunel University, United Kingdom E-mail address: suzanne.leroy@brunel.ac.uk Laminated sediments provide us with natural archives of high-resolution palaeo-climate and palaeo-environmental records. In most lakes around the world fine-laminated sequences were proven to be annual deposits that can be used to establish varve-based chronologies. Large portions of the Dead-Sea Basin Quaternary sections are comprised of mm-scale laminations of dark-detrital and white-carbonate laminae couplets that were deposited in a climate-controlled lacustrine environment. So far these laminae have been interpreted as forming seasonally (Heim et al., 1997, Leroy et al., 2010). Here we however hypothesize these laminae couplets represent brief flash-floods events delivering suspended fine sediments into the lake followed by chemical deposition rather than an annual cycle. It is critical to resolve the laminae temporal resolution in order to correctly interpret climatic trends and chronologies; therefore we propose to use pollen analysis to determine the laminae seasonality. We will test the presence or absence of the seasonal character of the laminae on the two laminated horizons from the sediment of the last 2000 years that has recently emerged along the shores of the Dead Sea, as well as on sediment forming in the last year. CONFLICTING VIEWS ON CLIMATIC AND SEA LEVEL CHANGES IN THE SOUTH BASIN OF CASPIAN SEA Suzanne Leroy. Institute for the Environment, Brunel University, United Kingdom E-mail address: suzanne.leroy@brunel.ac.uk Nowadays the Caspian Sea (CS) receives most of its water from the Volga River drainage basin. However during the Late Pleistocene and Early Holocene, the Amu-Daria, via the Uzboi, flew into the south basin of the CS. A sill separates the middle basin from the south basin. It shows signs of overspill. Reconstruction of past salinities, hence past sea levels, is done here from dinocyst assemblages whilst past climate is reconstructed using pollen and spores amongst other proxies. A series of cores taken in the south basin covers from the Lateglacial to the present. Various topics and unanswered questions will be presented such as the Last Glacial Maximum (high or low water level), the transition Pleistocene-Holocene (coincident or not with end of the Khvalynian and the end of the Eurasian icesheet), the 4 cal. BP transition (a late drop in sea level, role of western Himalayas and monsoon, and delayed expansion of temperate trees) and the Little Ice Age (high sea level stand). This will be discussed in relation with results from the middle basin, the regional climate and the sources of water for the Caspian basin. VARIOUS STYLES OF DEPOSITION OF PLEISTOCENE GLACIGENIC DEPOSITS IN ESSEX, ENGLAND Karolina Leszczynska. Cambridge Quaternary, Department of Geography, Uni, United Kingdom E-mail address: km429@cam.ac.uk The area of the Danbury-Tiptree in Essex, England is characterised by widespread outcrops of sands and gravels, which occur adjacent to the south-eastern margin of the Middle Pleistocene Lowestoft Formation till sheet that marks the Anglian ice-sheet margin. These deposits cap a substantial bedrock London Clay (Palaeogene) ridge. Although, this area was glaciated only once during the Anglian (Elsterian, MIS 12) Stage, several local ice-marginal fluctuations probably occurred. The ice overrode pre-existing fluvial sequences, particularly those of the pre-diversion River Thames. The interpretation of the Danbury-Tiptree sands and gravels remains controversial in spite of there having been a series of investiga- tions over the last 150 years. The architecture of the Danbury-Tiptree sands and gravels is not typical of ice-marginal features. Several hypotheses have been established concerning the origin and character of these deposits. Their morphology and internal structure have been attributed to glacio- tectonic deformation, however, deposits in the area have also been inter- preted as being of non-glacial fluvial origin. In addition they have also been interpreted as glacial outwash deposits. The main aim of this study was to describe the evolution of the Danbury-Tiptree deposits. The role of pre- existing London Clay bedrock ridge in the palaeoenvironmental history of this area will be reviewed. An attempt will be made to establish the relation between the evolution of the Danbury-Tiptree sands and gravels and regional drainage pattern, especially the pre-diversion River Thames. The poster will present the results of detailed fieldwork investigations. The variability of the deposition style in a relatively small ice-marginal area will be highlighted. This investigation will greatly clarify the Pleistocene stratigraphy of southern East Anglia. PALAEOBOTANICAL EVIDENCE FOR THE PATTERN OF RAINFALL VARIABILITY IN WESTERN VICTORIA, SOUTH-EASTERN AUSTRALIA Tara Lewis. School of Geography and Environmental Science, Mon, Australia E-mail address: Tara.Lewis@monash.edu High resolution, multiproxy records, from several lakes on the volcanic plains of western Victoria, south-eastern Australia, are providing evidence for a number of dry periods over the last 2000 years, rivalling that which has dominated the landscape over the last decade. Evidence is primarily from diatoms but, in shallow lakes where diatom preservation can be an issue and where aquatic macrophytes are important, pollen analysis is sensitively revealing variation in lake conditions. This sensitivity is increased where the presence of seeds allows identification of indicator taxa to species level. Significant dry periods are evident every few hundred years although determination of their exact frequency, duration and regional expression awaits age refinements from lead-210 and radiocarbon dating. Each dry period has a distinct palaeoecological signature that may suggest differences in intensity, climatic trigger or land use activity. CLIMATIC RECORDS FROM TROPICAL AUSTRALASIA – A SYNTHESIS FROM THE OZ-INTIMATE WORKGROUP Stephen Lewis. James Cook University, Australia E-mail address: stephen.lewis@jcu.edu.au The tropics is regarded as the major source of heat and moisture under the current climate regime, but its response during key climate intervals of the past has yet to be resolved satisfactorily. We present a synthesis of climate proxy data from tropical Australasia spanning the last 35 thousand years that includes speleothem, marine core, pollen, charcoal, coral and sedi- mentological records. Key changes in the climate event stratigraphy, such as the regional response during the Last Glacial Maximum, Younger Dryas, variations in the strength of the Australian monsoon, and the development of ENSO through the Holocene are well represented. This work is a contribution to the Aus-INTIMATE project. FORMATION OF NON-LINEAR TILL WAVES - A NUMERICAL MODELLING STUDY OF GLACIER ADVANCE OVER DEFORMING TILL Gwendolyn J.-M.C. Leysinger Vieli. Durham University, United Kingdom E-mail address: g.j.m.c.leysinger-vieli@durham.ac.uk Abstracts / Quaternary International 279-280 (2012) 233–345 277