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アカホヤ火山灰は、炭素年代では6300BP 頃、水月湖の年縞研究では、5330calBCとかなり絞り込まれているのにもかかわらず、考古学的には十分に絞り込めていない。このアカホヤの時の土器型式が絞り込めれば、災害と人類の関係について、踏み込んだ研究が行えるはずである。そこで、山陰地方：島根大学構内1 次遺跡を中心にアカホヤ前後の土器付着炭化物の年代測定を行った。その結果は以下の通りである。 較正年代で、島根大学構内1次式（5450-5300calBC）、西川津Ⅴ式（5100-4900calBC）、条痕文（4800-4500calBC）頃である可能性が高いことが明らかになった。, It is thought that K-Ah generated from Kikai caldera has a big eff ect on the society of the Jomon period. Although the age of K-Ah is about 6300 BP by the radiocarbon measurement of the charcoal and the limited 5330 cal BC by the research of the high resolution laminated sediments from Lake Suigetsu, there is no clearly evidence of the archeological research. If the pottery type of K-Ah can be clearly limited, we can make a thoughtful study of the relationships between the natural disaster and the adaption for human beings. At fi rst, we measured the 14C age of the charred material on pottery before & after K-Ah in the Sanin district: Simane university-kounai 1st site. The Results are as follows: Shimanedaigaku-kounai 1st Type (5450-5300 cal BC), Nishikawatu V Type (5300-5100 cal BC), Joukonmon (4250-4000 cal BC).

本稿では、モンゴル国ドルノド県ツァガーンオボー郡に位置する契丹（遼）時代に築かれた土城バルスホト１に隣接する仏塔の調査成果について述べる。2014年の仏塔調査においては、デジタル化および建築部材の年代測定を行った結果、一部の建築部材が16世紀から17世紀前半であることが判明した。このことから、この仏塔は、契丹（遼）時代に建立され、修築されている可能性を示したが、2014年から2016年にかけて大規模な修築が行なわれた。2018年の調査においては、ドローンと画像計測を用いて、バルスホト１および修築された仏塔をデジタル化した。さらに、この仏塔が、どの程度修築されているかを調べるために、2014年と2018年にデジタル化した仏塔をもとに、修築前後の構造を比較した。最後に修築に関する問題について考察した。

In electron spin resonance (ESR) dating, ESR age is obtained by diving total radiation dose by annual dose. To accomplish high precision of ESR dating, the total radiation dose needs to be determined more precisely. The scattering of ESR signal intensities obtained from individual irradiated samples is caused by the difference among radiation damage production rates which individual irradiated samples have, and leads to the lowing of precision of the total radiation dose and ESR age. I have tackled high-precision ESR dating by applying the correction for radiation damage production rate to ESR signal intensities obtained from individual irradiated samples, using fossil teeth and bones of bats collected from red clay sediments in Akiyoshi cave, Yamaguchi, Japan. A CO^-_2 radical center (g=2.003) derived from calcium phosphate minerals is detected from fossil teeth and bones of bats and regularly increases with radiation dose. After the correction for radiation damage production rate, the datermination factor (R^2) of regression line for the total radiation dose obtained from the fossil teeth increases from R^2=0.9086 to R^2=0.9897 and the high precision of ESR dating is accomplished, while that obtained from the fossil bones hardly changes and the high precision is not recognized. The difference in result is attributed to the shape of fossil bones. As a result of ESR dating, the formation ages of the fossil teeth and bones are estimated at 63±9～94±22 ka with high determination factors of R^2=0.82-1.99. These ESR ages are coincident with the radioactive age (7-9 ka) of Aso-4 tephra composing the red clay sediments.

The thermoluminescence (TL) dating method has been applied mainly in the field of archaeology and art history, for estimating the ages of heated artifacts such as ceramics. It is indispensably important for the research of ancient potteries to know the age of their manufacturing. In the present work, we applied a thermoluminescence method to the porcelain shards which were collected at the Woosan-ri porcelain kiln sites, Kwangju, Korea. The Woosan-ri porcelain kiln is considered to have been operated from 15th to 16th century according to several historical records. It is difficult to get the reliable ages by TL method for porcelain dating, because porcelains are almost glass formed from fused feldspar, and a little minute particle of quartz. In this research, we proposed an improvement condition for porcelain measurement by TL method. In this paper, the authors show the results of TL measurements, and discuss the validity and effectiveness of TL method for porcelain dating .The results of the present work correspond exactly with the archaeological fact. This result shows that TL dating is an effective tool for the research on the history of porcelain. Further improvement of TL measurements and accumulation of data should be desired for the future development in this field.

In the present paper, the authors report the results of thermoluminescence (TL) dating of the bricks from a modern structure, and discuss the validity of this method. TL method is a typical and well-used tool for estimating the age of heated relics. In this research, TL dating method applied to the bricks of the brickwork foundation of an officer' s mess hall which were excavated at the site of the 53th Infantry Regiment on the campus of Nara University of Education. In 1909, the 53 Infantry Regiment was located in the site, where the campus of Nara University of Education is now located. The Infantry Regiment site was first discovered in 2008. This site was excavated continuously between 2008 and 2011. And, the samples were collected at the Infantry Regiment site in 2011. The samples were measured according to the protocol of multiple aliquot additive dose. The TL age averaged for all samples is 96±10 years before present. Thus the results of the present work indicate that the bricks were burnt in the period around the early 20th century. The results are consistent with the ages shown from the archaeological aspects of view. The TL dating method was successfully applied to the modern burnt bricks. And the above result suggest that TL dating method is a valid technique for the research on the history of modern times.

In order to study about the formation and development of the rice paddy cultivation technology in East Asia, it is important to arrange correctly the result (data) taken in various fields, such as agriculture, botany, and archaeology, in the time and space. This report is discussing rice paddy cultivation of East Asia, introducing the result of the field survey in China or Japan. And, I also introduce about a part of result of the study (Study on age determination by carbon in plant opal collected from ancient agricultural field) which we are tackling now., 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

Meaning of chronological data for petrological studies was reviewed. Mizutani and Shibata (1983) estimated duration of lithification after initial deposition of sediment as 17 million years using a combination of radiolarian fossil and 87Rb-87Sr whole rock isochron ages. Harayama (1992) reported a youngest exposed granitoid pluton on Earth from the Northern Alps, central Japan, based on the K-Ar hornblende and biotite ages， Rb-Sr biotite age，and fission track zircon age. Metamorphic rocks generally record ages of many equilibrium stages during metamorphic evolution. Katayama (2004) confirmed five stages of zircon growth in ultra-high pressure metamorphic rocks from the Kokchetav massif，and estimated their exhumation speed as 0.5-0.6 cm/year using Secondary Ion Mass Spectrometry., 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

SLP IIでは、「知識」と「思考力」のどちらもが大切なのであるが、特に後期の「自然と科学」においては「思考力」、特に「科学的な思考」とは何か重点を置いて授業を行う予定である。「科学的な思考法の立脚点をつくるための学習」というテーマを設定し、少人数でものを考え、追求する体験をさせる機会とする。また、科学的思考を身近で体験するためのアプローチとして、数学的・物理学的・人文科学的なそれぞれの観点から三つのグループに分かれ、様々な観点から科学的リテラシーを身につけさせるための授業を展開した。

14C年代測定法は絶対年代を明らかにする最も一般的な方法といえ、AMS法や年代較正の発達によって、その有効性が高まっている。本論では愛鷹・箱根山麓の旧石器時代14C年代を集成して検討を行った。各層位の年代測定の現状を把握したうえで、測定結果が多いSCⅢ～BBⅠについては想定される14C年代値を示した。BBⅥでは分析機関により測定結果にずれがある可能性が明らかになった。この問題は、これまでなされた、そしてこれからなされる14C年代測定結果の有効性を揺るがす大きな問題であり、原因の解明が急がれる。仮定的ではあるが、SCⅢ～BBⅠについてはCalPal-2007Huluを用いて較正年代を明らかにした。だが、本論で示された較正年代は他地域の編年やATの年代とずれがあることが分かった。

Dated charcoal and humus materials in soil, both of which are evidence of forest fire, vegetation changes indicate occurrence of past deforestation and land development (paddy field) in Eastern Himalaya. Around the Ziro, Arunachal Pradesh, North Eastern India, human impact such as population growth and cultural changes may have accelerated an environmental and agricultural changes after ca. 2 ka BP. Relatively intense deforestation and land formation process occurring since the ca. 1 ka BP was due to the human impact.

Thermoluminescence（TL）dating by the total-bleach method has been used for the age determination of sediments. It is difficult to get the reliable ages by this method, because there is no routine method to check accurately the level of the residual TL. In this study, the amounts of residual TL of quartz fine grain (ca.1-8μm) samples were compared with those of residual OSL of the same samples by bleaching them with a 60-krx light source. As a result, we found that elapsed time of light exposure, which guarantees the residual OSL intensity nearly zero, can be a criterion to estimate the level of the residual TL. TL age of a Chinese loess deposit was estimated by the improved total-bleach method using the estimated residual TL comparing with the residual OSL. The TL age obtained was in good agreement with OSL age of the same loess sample.

The infrared stimulated luminescence (IRSL) dating was performed for the sedimentary samples from the Neolithic sites, Zaisanovka 1 site, Posiet 1 site and Ustinovka 3 site, in the Russian Far East (the Maritime Region). The IRSL samples were collected from the 3 and 4 layers at the Zaisanovka 1 site, the upper and lower layers of the cultural horizon at the Posiet l site and the III and IV layers at the Ustinovka 3 site. The paleodose of each sample was estimated by the multiple aliquot additive dose (MAAD) protocol with poly-mineral fine grain samples prepared from the collected sedimentary samples. The IRSL measurement conditions (detection wave lengths, measurement temperatures and preheat conditions) were determined according to the results of preliminary experiments using four types of standard feldspar specimen. Annual doses (dose rates) were estimated from the concentrations of U, Th and K-40 using a high-purity Ge gamma-ray spectrometer. The IRSL ages obtained are 1.9±0.8ka and 3.4±0.7ka for the Zaisanovka 1 site, 8.7±2.1ka, 14.9±2.5ka for the Posiet 1 site and 8.3±1.3ka, 11.0±0.8ka for the Ustinovka 3 site. The comparison of the IRSL ages with known C-14 data are also discussed.

Optically stimulated luminescence (OSL) of quartz, feldspar and fine grain mineruls was investigated with the intention of establishing the optimum condition for the OSL dating of geological and urchaeological sedimtents. Four quartes, five feldspars and natulal sediments were used for the OSL measurements stimulated with green and infrared lights. The tests were focuset on the temperature dependence of OSL intensities, the preheat-plateau tests, the effects of annealing and bleaching on zeroing and sensitivity changes and the thermoluminescence intensity of OSLmeasured sumples.

新大院博（理）甲第270号

平成15年度～平成17年度科学研究費補助金(基盤研究(C))研究成果報告書, サンゴ礁が海面上昇に対してどのようにレスポンスするのかを知ることは、サンゴ礁を海水準の指標として使ううえで重要である。そこで、沖縄のサンゴ礁において、サンゴ礁の上方成長を知る目的で、サンゴの飼育実験を行った。さらに、昨年から継続してフナフチ環礁コア試料およびハワイ大学に保存されているミッドウエイ環礁コア試料の年代測定を行った。沖縄のサンゴ礁でのボーリング結果、ハマサンゴは、1年間で約1-1.5cm上方成長することが明らかになった。さらに、沖縄のサンゴ礁から採取したハマサンゴの飼育実験の結果、サンゴの石灰化速度は、環境水の炭酸カルシウム(アラゴナイト)に対する飽和度と比例関係であることが明らかになった。したがって、大気中の二酸化炭素濃度の上昇は、海水のpHを減少(酸性化)させると伴にアラゴナイトに対する飽和度を減少させるので、サンゴ礁の上方成長を阻害することを水槽実験の結果は示した。フナフチ環礁ポーリングコアのストロンチウム同位体比、放射性炭素を測定し、年代測定を行った。その結果、150万年間で200メートルのサンゴ礁堆積物がフナフチ環礁に堆積したことが明らかになった。また、その堆積過程は連続ではなく、飛び飛びであり、間氷期-氷期のサイクルとの関係が推測された。すなわち、サンゴ礁の上方成長は間氷期にのみ上方成長するというモデルが本研究の結果明らかになった。その研究成果の1部は2004年6月に沖縄で開催された国際サンゴ礁シンポジウムで発表し、その後の分析データを加えて、 2006年に印刷公表される予定である。タイ湾およびセブ島のサンゴ礁調査結果は現在データを解析中であり、多くのサンゴ礁のデータをつなぎあわせることによって、過去の海面変動の歴史とサンゴ礁の上方成長、さらに津波に対する防波堤としての役割についても定量的に明らかにし、論文として公表する予定である。, The growth and depositional history of reef-buildings corals provide excellent records of the environment in which they grew. Using living corals collected from Okinawan coral reefs, laboratory experiments were performed to investigate the relationship between coral calcification and aragonite saturation state (Ω) of seawater at 25℃. Calcification rate of a massive coral Porites Iutea cultured in a beaker showed a linear increase with increasing Ω_ values (1.08-7.77) of seawater. The increasing trend of calcification rate (c) for Ω is expressed as an equation, c=aΩ+b (a, b : constants). When Ω was larger than 4, the coral samples calcified during nighttime, indicating an evidence of dark calcification. This study strongly suggests that calcification of Porites lutea depends on Ω of ambient seawater. A decrease in saturation state of seawater due to increased pCO_2 may decrease reef-buildings capacity of corals through reducing calcification rate of corals. The drill core of Funafuti Atoll, collected by the Royal Society Coral Reef Expedition in 1896-8, has been dated using high-precision ^C and Sr isotope measurements determined by mass spectrometry. The core top is a Holocene reef deposit, reflecting 26.4m of reef growth since 8 ka, and is underlain by Pleistocene reef-lagoonal deposits separated by a series of inferred hiatuses at 26.4 m, 30 m,〜65 m and 〜80 m(〜0.1 Ma,〜0.2 Ma,〜0.3 Ma and 〜0.6 Ma, respectively), reflecting atoll carbonate deposits associated with late Quaternary sea-level changes. In turn, the underlying sequence below 〜80 m comprises an upper section of additional Pleistocene reef-lagoonal deposits, having a high accumulation rate >100 m/Ma, and a heavily dolomitized lower section. Sr isotope data in the lower section provide maximum (oldest) ages for dolomite formation and, depending on the extent of the isotopic memory from precursor CaCO_3, reflect ongoing diagenetic alteration from 〜2.3 Ma (i.e., the oldest dolomite) or in one or more discrete diagenetic events at 〜1 Ma, and possibly at 〜2 Ma. The coral reef sequence reflects interaction between atoll carbonate sedimentation, tectonic subsidence, and eustatic sea-level change. We also performed the chronology of Midway atoll and would like to publish the results. Such deep coring projects are expensive and cores are therefore difficult to obtain for scientific purposes. The sea-level signatures recorded by deep cores in subsiding areas are therefore rare and precious. These two methods are especially useful for correlations between global warning and sea-level rise. A blending of such information from two very different approaches might clarify eustatic sea-level changes., 未公開：P.4以降（論文別刷のため）

Thermoluminescence (TL) dating by pre-dose method was made for the earthenwares obtained from Shibayama site, in Kyoto prefecture, which consists of several small kofuns (ancient tombs), sheds, ditches and a well from the Ko fun to Heian periods. Pre-dose method was applied to 5 of 7 shards and 4 0f them were analyzed by quartz inclusion method. The annual gammaィay dose rates were estimated, in situ, using the TL dosimeters (Matsushita UD-110S) mounted in dosimetery sets with polyethylene and copper tubes. One of the data by pre-dose method were analyzed assuming that the saturation of sensitization in 80℃ peak is due to that of hole concentration in hole trap R in Zimmerman's band model. The results obtained by pre-dose method agreed with archaeological ages as well as the results by quartz inclusion method.

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In an earlier paper of this bulletin, the authors described how the thermoluminescent (TL) method may be an effective one for the dating of ancient pottery and it has an advantage over radiocarbon method. The present paper is concerned with some salient points in the development of the TL technique at our laboratory during the past 10 years. The results recently obtained from the typical potteries are shown, which contain the dating results for a series of shards from Ban-Chiang and those for a series of shards from Nara. The quartz and feldspar embedded in clay matrix have been exposed by the natural radiation since the last heating. The TL emitted from the ancient pottery is a measure of the total dose of this radiation. On the assumption that the natural dose-rate has been constant, the time elapsed since the firing of the pottery is estimated from the accumulated radiation dose and the dose per year. The TL dating used in the present investigation is the method which is known by the name of the inclusion method or the large grain method. For the estimation of the accumulated radiation dose we measured the TL of qualtz and feldspar inclusions with diameters of greater than 0.3 mm. Consequently, we could neglect the contribution from alpha particles which will only penetrate into the inclusions approximately 0.023 mm on average and are typically only from 10 to 20 % as efficient as beta or gamma radiation in the creation of TL. The environmental radiation and the radiation from the pottery itself were measured with CaSO4; Tm TL dosimeter developed by Matsushita Electric Ind. Co., Ltd.