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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

加速器質量分析計を用いた鉄製遺物の14C年代測定に関する基礎研究

NAKAMURA, Toshio, KONDO, Hiroki, 中村, 俊夫, 近藤, 宏樹 03 1900 (has links)
名古屋大学年代測定総合研究センターシンポジウム報告
42

チベット湖沼堆積物の年代決定とモンスーン活動の復元

NISHIMURA, Mitsugu, KAKEGAWA, Takeshi, MINOURA, Koji, NAKAMURA, Toshio, MATSUNAKA, Tetsuya, NARA, Fumiko Watanabe, WATANABE, Takahiro, 西村, 弥亜, 掛川, 武, WANG, Junbo, ZHU, Liping, 箕浦, 幸治, 中村, 俊夫, 松中, 哲也, FAGEL, Nathalie, 奈良, 郁子, 渡邊, 隆広 03 1900 (has links)
名古屋大学年代測定総合研究センターシンポジウム報告
43

チベット高原南東部プマユムツォ湖大島から採取した土壌(陸成堆積物)の^<14>C年代測定

KAKEGAWA, Takeshi, NARA Watanabe, Fumiko, HORIUCHI, Kazuho, SAKAI, Takahiro, MATSUNAKA, Tetsuya, NISHIMURA, Mitsugu, NAKAMURA, Toshio, WATANABE, Takahiro, ZHU, Liping, 掛川, 武, 奈良, 郁子, LIN, Xiao, 堀内, 一穂, 酒井, 貴悠, 松中, 哲也, 西村, 弥亜, 中村, 俊夫, 渡邊, 隆広 03 1900 (has links)
第22回名古屋大学年代測定総合研究センターシンポジウム平成21(2009)年度報告
44

シベリア・チベット地域の湖沼から採取した湖底柱状堆積物の放射性炭素年代測定一4 : PY608E-PC コア試料(チベット・プマユムツォ湖)

ZHU, Liping, WANG, Junbo, KAKEGAWA, Takeshi, NARA Watanabe, Fumiko, MATSUNAKA, Tetsuya, NISHIMURA, Mitsugu, NAKAMURA, Toshio, WATANABE, Takahiro, ZHU, Liping, WANG, Junbo, 掛川, 武, 奈良, 郁子, 松中, 哲也, 西村, 弥亜, 中村, 俊夫, 渡邊, 隆広 03 1900 (has links)
No description available.
45

Environmental changes associated with Native American land use practices a geoarcheological investigation of an Appalachian watershed /

Mihindukulasooriya, Lorita N. January 2009 (has links)
Thesis (M.S.)--Ohio University, November, 2009. / Title from PDF t.p. Includes bibliographical references.
46

Regional Precipitation Response to Enhanced Monsoon Circulation through the Holocene Using Closed-Basin Paleolakes on the Tibetan Plateau

Hudson, Adam Michael January 2015 (has links)
The history of climatic changes in the Asian Summer Monsoon system over the Tibetan Plateau during the Holocene has been the subject of significant research due to the importance of the plateau as the headwaters for many major rivers providing water resources to the surrounding large, populous countries. In general, previous research has concluded that monsoon rainfall and summer temperatures peaked during the early Holocene (9-11 ka BP) in Tibet, coincident with peak Northern Hemisphere summer insolation. Atmospheric teleconnections with upstream Northern Hemisphere westerly circulation patterns influenced by North Atlantic sea surface temperature changes have also been noted at millennial and centennial timescales. However, recent studies have noted that the timing of peak monsoon warmth and wetness during the Holocene are not synchronous across the entirety of the Tibetan Plateau, and studies of modern precipitation indicate several distinct regions of monsoon precipitation variability at interannual scales, suggesting the monsoon response to past and future climate change may be regionally heterogeneous for the plateau. Clear assessment of this regionality within the monsoon climate region is a topic of continuing research, but it has been hindered by lack of climate records in remote areas, dating difficulties, and concerns over the comparability of interpreted climate-proxy relationships between the many different biological, hydrological, and geochemical proxies applied. The first part of this dissertation uses ¹⁴C and U-Th series geochronology, sedimentology, and GIS analysis of exposed lake shoreline sediments surrounding the numerous closed-basin lake systems of the central and western Tibetan Plateau to investigate regional heterogeneity in monsoon rainfall, and to develop a new well-dated lake level record from the Ngangla Ring Tso lake system in the poorly studied southwestern region. The major conclusions are: 1) peak early Holocene monsoon rainfall, recorded by the highest paleoshorelines surrounding 130 lake systems, intensified more relative to today in the western part (west of 86°E longitude) of the Tibetan Plateau when compared to eastern regions, closely following regions of modern rainfall variability; 2) monsoon rainfall in the Ngangla Ring Tso region peaked during the early Holocene insolation maximum, consistent with other records, remained significantly higher than modern until ~6.0 ka BP, but with abrupt reductions in monsoon rainfall associated with North Atlantic ice-rafted debris peaks. The warm and wet period of the early and middle Holocene was also likely coincident with the first major colonization of the Tibetan Plateau by prehistoric humans. Current research suggests early foragers employing stone tools first forayed into the middle elevation areas above 3,000 m elevation on the northeastern fringe of the plateau as early as 14.8 ka BP, and therefore the dominant hypothesis suggests plateau colonization proceeded from this direction, heading westward through the Holocene. However, well studied and dated archaeological sites from the high plateau are exceedingly rare, requiring further investigation. The second part of this dissertation presents new age controls for the Holocene Zhongba microlithic site in the southwestern Tibetan Plateau, using ¹⁴C dating of organic and carbonate-rich paleo-wetlands sediments hosting in situ stone artifacts. The major conclusions of this study are: 1) artifacts at the Zhongba site, which are typologically similar to microlithics across the plateau, can be no older than 6.5 ka BP, consistent with the prevailing east-to-west colonization hypothesis, and 2) microlithic tools continued to be important as late as 1.3 ka BP at the site, even though metal is found in sites of similar age elsewhere in Tibet.
47

Lake sediments around the Antarctic Peninsula : archives of climatic and environmental changes

Zale, Rolf January 1993 (has links)
Lakes and lake sediments from four areas around the Antarctic Peninsula are described. The concentrations of trace metals in sediment are found to be a useful tool in distinguishing between the different sedimentary phases during a transition from marine to limnic environment. A tephrochronology based on Deception Island tephra is developed, and used to cross date sediments from different lakes in order to overcome the radiocarbon dating problem of the area. The fluctuating concentrations of copper and phosphorus from penguin guano in the sediment of Lake Boeckella are used as a proxy for the penguin inpact on the sediment, and the size of the penguin rookery on the shores of the lake. Anthropogenic activities in the area, as well as climatic changes are discussed in relation to the rookery size. A radiocarbon dating model developed for the sediment of Lake Boeckella showed that the radiocarbon correction factor in the sediment depends on the amount and apparent age of the penguin guano washed down into the lake, and the amount of particulate carbon from the watershed present in the sediment. Neither the "old" meltwater from the glaciers nor dissolved carbonates contributes significantly to the correction factor. The model is used to achieve more accurate radiocarbon dates of the Lake Boeckella sediment. This model, or a modified version, may contribute to a higher dating accuracy and a better understanding of the dating problems in Antarctica. Deglaciation dates, as well as data on the climatic and environmental history of Byers Peninsula on Livingston Island, South Shetland Islands, of Hope Bay, Antarctic Peninsula and of Hidden Lake area, James Ross Island are given. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1993, härtill 6 uppsatser.</p> / digitalisering@umu
48

Gristhorpe Man: an Early Bronze Age log-coffin burial scientifically defined

Melton, N., Montgomery, Janet A., Knüsel, Christopher J., Batt, Catherine M., Needham, S., Parker Pearson, M., Sheridan, A. January 2010 (has links)
A log-coffin excavated in the early nineteenth century proved to be well enough preserved in the early twenty-first century for the full armoury of modern scientific investigation to give its occupants and contents new identity, new origins and a new date. In many ways the interpretation is much the same as before: a local big man buried looking out to sea. Modern analytical techniques can create a person more real, more human and more securely anchored in history. This research team shows how.
49

Öjingsvallen vid sjön Öjingen : en pollenanalytisk studie av en fäbodvall i Ängersjö, Hälsingland /

Karlsson, Hanna. January 2001 (has links) (PDF)
Examensarbete. / Examensarbete i biologi.
50

Processes controlling production and transport of dissolved organic carbon in forest soils /

Fröberg, Mats, January 2004 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2004. / Härtill 5 uppsatser.

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