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Abstracts / Quaternary International 279-280 (2012) 346–461 447
B.P.) is characterized by the establishment of trapezoid industries associ-ated with edge-ground stone axes. These industries are considered to havebeen derived from scraper/flake industries lacking blade techniques,which represent the first prevailing lithic industries. X-ray fluorescenceanalysis has revealed that the discovery and exploitation of obsidiansources located at high mountainous areas (1,200-2,000 m) and a Pacificisland (Kozu island,>60 km away from the mainland) date back to as earlyas the initial Upper Palaeolithic. These explorations were achieved in thecourse of comprehensive surveys for natural resources conducted by thefirst immigrants to the archipelago. With the beginning of the early UpperPalaeolithic (35-30 kyr cal. B.P.), blade techniques, elaborate grindingmethods for axe using whetstones, and the management of non-local rawmaterials were established. Although biology of the immigrants isunknown in terms of fossil record, all archaeological evidence indicatesthat the first immigrants reaching the Japanese Archipelago from the Asiancontinent were behaviorally modern humans. The movement has beenrightly connected to the wave of modern human dispersal into the easternpart of Eurasia.
RECONSTRUCTION OF THE EAST ASIAN SUMMER MONSOONALVARIABILITY IN THE NORTHERN JAPAN SINCE THE LAST DEGLACIATIONBASED ON d13C TIME SERIES OF PEAT CELLULOSE
Tetsuya Shinozaki. University of Tsukuba, JapanE-mail address: [email protected]
The East Asian summer monsoon (EASM) is one of the most importantcomponents that influence the East Asian climate. People living aroundEast Asia depend on food supply supported by EASM rainfall, however,monsoonal rainfall fluctuations often derive devastating floods and/ordrought. A critical question is whether, and how, a rapid and significantchange in global climate might affect the monsoon system. Stable carbonisotope ratio of peat cellulose (d13Ccellulose) is used as a proxy indicator forprecipitation amount. EASM variability in northern Japan, associatedcontinental water cycle, was investigated using d13Ccellulose. Here, wepresent East Asian monsoon variability and their linkages with globalclimate system during the last deglaciation in the northeast Japan, usingpeat cellulose d13C of high time resolution peat archive.We used 8.8 m length peat core corrected from the Tashiro bog, northernJapan. We conducted total 53 14C measurements, and found the corebottom reached to 15.5 ka. We discussed about peat cellulose extractionsto investigate more suitable 14C chronologies because peat containsvarious organic matrixes with old carbon contamination. The results ofd13Ccellulose showed clear variations with higher values during warmperiods (B/A, PB) and lower values during cold periods (YD, 8.2 ka), sug-gesting that it is wet summer in the cold periods and dry in the warmperiods. Similar patterns of d13Ccellulose were reported in Hani peat bog, atnortheast China (Hong et al., 2005). On the other hand, these results hadanti-phase synchronization at Tibet significantly influenced with Indianmonsoon (Hong et al., 2003).Our high-resolution d13Ccellulose records highly coincided with EASMvariations during the abrupt climate changes, suggesting that the stronglinkages with global climate system.
PALEOCLIMATIC AND PALEOENVIRONMENTAL EVOLUTION SINCE THELATE GLACIAL EPOCH IN JIANGHUAI PLAIN
Qiang Shu. College of Geography Science, Nanjing Normal Unive, ChinaE-mail address: [email protected]
Abstract: The Jianghuai Plain located not only in themargin area of Chineseimportant climate separatrixdQinling -Huaihe River but also in theMonsoon triangle Area of china, under the influences of the East Asianmonsoon, very important in recording the East Asian monsoon changes. Asediment core from Jianghuai plain was chosen for the study. Base on theanalyses of chronology, magnetic susceptibility and Grain Size of YZQ CoreSediments form Jianghuai Plain, the climate history of the jianghui plainduring the last 19230 cal a B.P. was revealed as cool and dry (19230-14150cal aBP) warm and wet(14150-12950 cal aBP) cool and dry(12950-11290 cal aBP) warm and wet(11290-7450cal aBP) temperate and
dry(7450-4950cal aBP) warm and wet(4950-1510 cal aBP). In addition, theindexes also recorded several climate events, Older Dryas, Younger Dryas,8250 cal aBP and 3500-2500 cal aBP events are obviously. Most signi-gicantly, the similarity which can be observed among the fluctuation ofclimate proxies in this paper, the GULIYA ice core d18O record, theGreenland GISP2 ice coreCH4 record and the Sanbao/Hulu's stalagmited18O record shows that climate change of the studied area may have globalbackground, and on the other hand, it also incarnates evident regionalcharacteristics.
GROUND PENETRATING RADAR (GPR) STUDIES ALONG THE SWKACHCHH COAST, WESTERN INDIA: IMPLICATIONS INRECONSTRUCTING HIGH ENERGY EVENT HISTORY
S.B. Shukla. Department of geology, The M.S. University of Baro, IndiaE-mail address: [email protected]
The Kachchh coast is the northern flank of Gulf of Kachchh – one of thelargest macrotidal regime in southeast Asia. The South-West coast ofKachchh coastline is about 100km long and is sandy in nature, comprisingof series of barrier ridges and dunes along its length. The coastline is idealfor evaluating the application of ground penetrating radar as it is anexcellent non-destructive technique in studying the shallow subsurfacearchitecture of sedimentary bodies. Totally four sites were studied wheretraverses across the coastline covering these various landforms werecollected using GSSI SIR-20 GPR systemwith 200MHzmonostatic shieldedantenna. The raw GPR data were processed with Radan 5.0 software andvarious sedimentary body related radar facies bounded by several radarbounding surfaces were interpreted. Major radar facies identified usingGPR were Beach Ridge facies (Br) with parallel concave downward seaward dipping reflectors, Washover facies (Wo) with concave downwardtangential and land ward inclined reflectors and Coastal dune facies (Cd)with sub-parallel cross bedded reflectors. The Kachchh coastline, asevidence by the GPR profiles, is characterized by beach-ridge-dunecomplex along its entire length. The thickness of dunes and beach ridgesincreases at eastern end (about 1km), which is due to littoral drift ofsediments in longshore currents. The conspicuous presence of washoverdeposits on the landward side of these beach ridges and coastal dunes issymptomatic to the region being prone to high energy coastal events(storms/tsunamis). The truncations of these washover deposits overcoastal dunes and beach ridges is quite fascinating in terms of the recon-structing the frequency of these high energy events in the region. GPRproves to be very useful tool in aiding the study to delineate the subsurfacecoastal sedimentary body geometry, which has immense implications inevaluating the frequency of these high energy coastal events of inundation.
THE CHRONOLOGY OF THE LAST DEGLACIATION FROM TWO NEWZEALAND VALLEYS AND THE CONTRASTING ROLES OF CLIMATE ANDGEOMORPHOLOGY
James Shulmeister. University of Queensland, AustraliaE-mail address: [email protected]
We present Be-10 and Al-26 chronologies from the paleo-Rakaia glacierand the Clearwater lobe of the Rangitata glacier focussing on the transitionfrom the last glaciation maximum (LGM) to the Holocene. From the Rakaiawe demonstrate that the local glacial maximum preceded the global LGMby several thousand years at c. 25 ka. Over the succeeding 12,000 years theglacier retreated only about 10 km and although undated, geomorphicevidence suggests a continued steady retreat after this time. The Clear-water lobe of the Rangitata glacier provides the most detailed LGIT recordfrom any New Zealand glacier because it the valley was protected fromsignificant meltwater flow during the deglaciation. Between 16.4 ka and13.7 ka the Clearwater ice lobe retreated only 12 km producing 23 closelyspaced recessional ice positions. The geomorphology and chronology arecategorical in demonstrating that no significant re-advance can haveoccurred during this period. The inboard termination of the record occurswhere the Clearwater valley drops into the main Rangitata Valley andshould not be interpreted as the start of the more significant retreat. Wehighlight that uncertainties in isotope production rates and other elements
