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Kitaba I.,Kobe University | Harada M.,Kobe University | Hyodo M.,Kobe University | Katoh S.,Museum of Nature and Human Activities | And 2 more authors.
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2011

We report climate and sea-level variation for the marine oxygen isotope stage (MIS) 21, encompassing the end of the Mid-Pleistocene climate transition (MPT), based on pollen, diatom, and sulfur records from a 50-m thick sequence in a core from Osaka Bay. An extremely warm climate coincided with the sea level highstand of substage 21.5, when the warm-temperate element Quercus (Cyclobalanopsis) exceeds 40% of total arboreal pollen. This was followed by a warm-temperate to temperate and humid climate that continued until the end of MIS 21. A linear age model shows that climate was dominated by precessional cyclicity, with an inverse correlation between temperature and precipitation. The postglacial sea-level rise reached its highest peak in substage 21.5, when paleo-Osaka Bay reached its maximum extent including Kyoto and Nara Basins. At this time pelagic diatoms were dominant in the central part of the bay. Sea level dropped below the Osaka Bay sill (about -60. m at present) during substage 21.4, followed by a rise above the sill in substage 21.3, and a drop at 21.2. Sea level remained below the sill during substage 21.1. The thermal maximum and sea level peak occurred just after the rapid postglacial sea level rise, after which there was a gradual decline in temperature and sea level accompanied by precession-related oscillations; these features are typical of the post-MPT interglacials dominated by 100-ka cyclicity. These features may be a sign of termination of the MPT. © 2010 Elsevier B.V.

Okuyama M.,Archaeological Institute of Kashihara | Sato M.,Nara National Research Institute for Cultural Properties | Akada M.,Kyoto Institute of Technology
Sen'i Gakkaishi | Year: 2011

The ionic liquid is a salt which is usually liquid at room temperature. The vapor pressure of ionic liquid is so low that vaporization during experiment is disregarded. The utility of ionic liquid was revealed for the prevention of charge up phenomenon of fiber samples in the SEM observation. The ionic liquid used in this investigation was 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI-BF4). The textile samples were modern hemp, silk and excavated fibers from a tumulus (early Kofun Period) in Nara prefecture. Prior to the SEM observation, fiber samples were soaked in 0.1 M EMI-BF4/ethanol solution for 5, 10, 30, 60 minutes, respectively. The all of soaked samples showed distinct SEM images compared with that of Au-sputtered procedure irrespective of soaking time. The modern silk fibers showed however clear SEM images only at low magnification. Besides, the SEM images were distorted at high magnification due to the charge up phenomenon. Though excavated samples also gave clear SEM images, they were separately investigated by FT-IR microscopy to find out any changes in chemical composition before and after soaking treatment. Any appreciable changes were not found even after soaking. In summary, EMI-BF4 soaking was superior to prevent the charge up phenomenon of fibers and hence to obtain clearer SEM images compared with that of Au-sputtering procedure. Besides, in connection with the versatility of sample preparation procedure, EMI-BF4 is an appropriate reagent for SEM observation of textile materials.

Okuyama M.,Archaeological Institute of Kashihara | Sato M.,Nara National Research Institute for Cultural Properties | Akada M.,Nara National Research Institute for Cultural Properties
Sen'i Gakkaishi | Year: 2014

The precise identification of bast fibers such as ramie and hemp found at several archaeological sites is a very difficult problem because organic materials are usually heavily degraded during the long term preservation at underground or mound. Both excavated ramie and hemp usually show very similar degraded FT-IR spectra (glober light source). The authors are continuing to study the identification of several kinds of archaeological silk and vast fibers using BL43IR beam line (FT-IR micro-spectroscopy) at SPring-8. It has already known that excavated ramie and hemp show the possibility of distinguish ramie from hemp under polarized light source. In this report, various modern ramie fibers are analyzed by detailed IR polarization measurement. As a result of the measurement, the absorption band of 1160 cm-1 disappeared at 45° (angle of polarizer) irrespective of sample history. In the next measurement, the disappearance angle of specific peak of modern hemp (several origins) will be confirmed. The determination of specific disappearance of certain peak for ramie or hemp will be effective for the identification of each fiber.

Tei S.,Hokkaido University | Sugimoto A.,Hokkaido University | Yonenobu H.,Naruto University of Education | Hoshino Y.,Nara National Research Institute for Cultural Properties | Maximov T.C.,Russian Academy of Sciences
Quaternary International | Year: 2013

We present a dendroclimatic reconstruction of Palmer Drought Severity Index (PDSI) in Yakutsk (62° 14'N, 129° 37'E), East Siberia using a larch tree-ring (latewood) δ13C chronology (1780-2008 AD). The correlation function analysis showed significant positive correlations between earlywood, latewood and total ring width and July PDSI of the previous summer. On the other hand, tree-ring δ13C from earlywood, latewood and total ring showed significant negative correlations with July PDSI in current summer, of which latewood δ13C showed highest correlation with PDSI. A moving-window correlation analysis demonstrated that the temporal stability in correlation between tree-ring variables and PDSI was highest when July PDSI was compared with latewood δ13C. Tree-ring δ13C values were corrected by taking account of both the changes in the isotope ratio of atmospheric CO2 (δ13Ca) and the plant physiological response to changes in atmospheric CO2 concentration (Ca). This correction significantly improved the sensitivity of larch tree-ring δ13C to PDSI, demonstrating that the correction is useful in building a reliable model to estimate past changes in PDSI. Our study shows that larch tree-ring δ13C has enough potential to reconstruct July PDSI series. Using a liner regression model, July PDSI was reconstructed from latewood δ13C over the last 229 years. The reconstruction showed an interannual to decadal wet/dry fluctuation with a decreasing trend from 1780 to 1960, suggesting that aridification progressed at least after the late Little Ice Age in East Siberia to the modern period of global warming. © 2012 Elsevier Ltd and INQUA.

Tamura T.,Nara National Research Institute for Cultural Properties | Oga K.,Nara Women's University
Microchemical Journal | Year: 2016

This study examines the chemical compositions, colorants, and bead-making techniques of natron glass beads excavated in Japan. The authors classified the natron glass discussed in this study into seven main types, as well as other minor types, based on their chemical compositions. We also compared these specimens with natron glass excavated in the Mediterranean world. Type B2, which was distributed in the first half of the 5th century CE, corresponds to Levantine I type; Type A1, which was distributed mainly in the 2nd century CE, is likely to correspond to specimens containing antimony only as decolorant. However, others do not obviously match any existing groups. The results of the measurement of lead isotope ratios revealed relatively similar values between the natron glass analyzed in this study and the ore containing lead found in Iran. This showed the origin of cobalt added as colorants. © 2015 Elsevier B.V.

Kirino F.,Tokyo University of the Arts | Kitada M.,Nara National Research Institute for Cultural Properties
Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals | Year: 2015

The microstructures of a corrosion layer formed on the surface of two Japanese oldest coins, Wadoukaichin (surface color: dark brown and green) were studied. Compositions of these coins are that main element is Cu and Sn and traces are Pb, Fe and As. X-ray diffraction patterns show that copper di-hydroxide (Cu(OH)2 2H2O), CuuiS and Cu2O are detected on the surface corrosion layer of dark brown sample, and Cu2(CO3) (OH)2 (malachite), Cu3(CO3)2(OH)2 (azurite) and Cu2O are detected on the surface corrosion layer of green sample. Optical microscope images show that the surface corrosion layer of dark brown sample is porous, and blue and green grains on the brown layer are existed on that of green sample. From spectrographs of these grains, the peak wavelength of green grains is matched to that of malachite, but this of blue grains is shifted to long wavelength side of about 40 nm at azurite on an influence of trace contaminations. The corrosion layer has two layers, surface layer is plate-like texture, and under layer is aggregation microstructure from TEM observation. The crystal structure of these two layers is matched to azurite from the electron beam diffraction patterns. © 2015 The Japan Institute of Metals and Materials.

Kitadai A.,J. F. Oberlin University | Nakagawa M.,Tokyo University of Agriculture and Technology | Baba H.,Nara National Research Institute for Cultural Properties | Watanabe A.,Nara National Research Institute for Cultural Properties
Proceedings - 10th IAPR International Workshop on Document Analysis Systems, DAS 2012 | Year: 2012

We have many historical documents written in over 1,000 years ago. Shape features of character patterns on the documents are unstable or missing because most of the documents have been stained and degraded deeply. Digital archives of the documents with accurate character pattern retrieval methods are helpful for archaeologists and historians. In this paper, we propose a similarity evaluation method for character patterns with missing shape parts. It collaboratively works with non-linear normalization for such patterns, and modifies the templates for each trial of the retrieval efficiently. In the experiences using 4,911 Kanji (Chinese origin) character patterns from the Japanese historical documents called mokkans, the method shows improvements of the retrieval accuracy. Also, we present a simple implementation of gradient feature extraction to compare the chain code feature with the gradient feature in the retrieval. As the result, the gradient feature works better than the chain code feature. © 2012 IEEE.

Li Z.,Henan Provincial Institute of Cultural Relics and Archaeology | Kunikita D.,University of Tokyo | Kato S.,Nara National Research Institute for Cultural Properties
Quaternary International | Year: 2016

In the Chinese context, pottery that predates ca. 9000 14C BP is referred to as "early pottery". Research on the early pottery of China had been conducted mostly in central and southern China; in contrast, research in northern China has been restricted, and only 5 sites had been discovered to date. Therefore, additional data is needed to foster the progress of research on early pottery in northern China. Given this situation, there is great value in the investigation of the many potsherds associated with microblade industry that have been found in secondary sediments of Layer 5 of the Lingjing site in Henan Province, on the Huang-Huai Plain at the southern end of the North China Plain.Based on AMS 14C dates (ca. 9.8 cal ka), typological features of the pottery, and features of the other artifacts found at Lingjing, these potsherds are argued by this paper to be examples of early pottery, meaning that Lingjing constitutes a new site yielding early pottery in northern China. Other than these archaeological results, our research on Lingjing pottery has also yielded primary data on stable carbon/nitrogen isotope analysis and starch residue analysis.On the basis of archaeological research on early pottery, including examples from Lingjing, it appears that pottery in northern China generally emerged at the beginning of the Holocene (11.7 cal ka). Therefore, this emergence of pottery was likely related to the rapid warming just after the end of the last glacial period, after the Younger Dryas. The archaeological evidence also indicates increasing utilization of plant resources and diversification of food resources beginning prior to that time, suggesting that early pottery may have played a major role in this change in subsistence strategy in northern China.Archaeological comparisons between the early pottery of northern and central/southern China show substantial differences. Based on its association with microblade technology and on characteristic features such as vessels with a flat base, this early pottery from northern China may be related to that from regions further north, such as the Russian Far East. © 2016 Elsevier Ltd and INQUA.

Kato S.,Nara National Research Institute for Cultural Properties
Quaternary International | Year: 2014

Analyses of microblade industries shed light on the human dispersal and technological diffusion in the terminal Upper Paleolithic of East Asia. From ca. 27-17ka, with the advances of the Last Glacial Maximum (LGM), the Mammoth Steppe and its associated mammoth fauna shifted southward. In the wake of these changes, human groups with the Northern Microblade Industries (NMI) also migrated southward to Northeast China. NMI did not appear in North China, so it is presumed that those migrating human groups did not extend their activity areas beyond NE China. Meanwhile, the human groups with small flake tool industries in North China appear to have interacted with those groups with NMI at the ecological border area between NE. China and N. China, and obtained the microblade technology of pressure flaking, wedge-shaped micro-cores, transverse burins with marginal retouch and other elements of NMI, leading to the formation of the microblade industries that are unique to N. China. Technological elements of the NMI that appeared in N. China are regarded as the result of external expansion diffusion. Among the distinct features of the microblade industries in N. China is the microblade technology based on pyramidal micro-cores. This technology was transferred to Southwest Japan. This transfer of microblade technology and its spread across SW Japan was carried out through the materials and information exchange network that had connected N. China and SW Japan since the pre-stage of microblade industry. This diffusion of microblade technology is also regard as an example of external expansion diffusion. From ca. 17-9ka, human groups that were migrating with NMI through NE China were able to enter N. China because of their flexible "collector" subsistence strategy and high level of adaptability to the environment. The appearance of NMI in N. China is regard as the result of external relocation diffusion. The technological transfer also occurred between the migrating human groups and the indigenous groups. The indigenous ones in turn adopted the technology of NMI, invented small bifacial points. This process is an example of expansion diffusion. © 2014 Elsevier Ltd and INQUA.

Morisaki K.,Nara National Research Institute for Cultural Properties | Sato H.,University of Tokyo
Quaternary International | Year: 2014

Drastic climate fluctuations occurred during the Late Glacial (LG), around 15,000-11,500calBP also in the Japanese Archipelago. Although some studies have claimed that regional differences in the characteristics of lithic technology and human behavior became apparent at this period, recent studies have revealed that they were already apparent as early as the Last Glacial Maximum (LGM).Hence, it is important to discuss whether or not the regionality of the LGM had changed by the LG, and to understand the socioecologial processes of the Pleistocene/Holocene transition. This paper aims to review lithic technological variation in the Japanese Archipelago before and during the LG, and to investigate behavioral diversity in detail, focusing on the Kyushu region in southwestern Japan.As the result of the analysis, there are clear differences between northern and southern Kyushu in terms of lithic technology and behavioral strategy. The differences between the two regions continued from the LGM to LG.Low lithic tool diversity in the northern Kyushu indicates high mobility frequency of humans who carried them. In addition, a high degree of curated reduction strategy, and non-local high quality lithic raw material use also implies a high magnitude of mobility. Curated microblade technology had long helped humans to transport and utilize obsidian lithic resources in a wide foraging territory. This supposition would be supported by the scarcity of archaeological feature there, as well.By contrast, plenty of archaeological features including trap-pits and pit-dwellings in southern Kyushu implies, as many previous studies claimed, slightly early establishment of sedentary life-way of human groups who inhabited there. High lithic tool diversity in the southern Kyushu means low mobility frequency of humans who carried them, and moreover, the low degree of standardization of flake removal technique, low degree of curated reduction strategy, and the scarcity of use of exotic lithic raw materials all strongly denote that their mobility magnitude was also considerably low. They must have adopted fine-grained resource exploitation strategies in small foraging territories. It is supposed that above differences of behavioral strategy could be explained as different adaptations to different regional environmental settings. Future investigation would clarify more detailed regional adaptation strategy than ever. © 2014 Elsevier Ltd and INQUA.

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