| Project/Area Number |
09680177
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
自然地理学
|
|---|
| Research Institution | HIROSHIMA UNIVERSITY |
|---|
Principal Investigator |
OKUMURA Koji HIroshima University, Faculty of Letters, Associate Professor, 文学部, 助教授 (10291478)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
YAGI Hiroshi Yamagata University, Faculty of Education, Associate Professor., 教育学部, 助教授 (40292403)
SUZUKI Takehiko Tokyo Metropolitan University, Graduate School of Science, Assistant Professor, 理学部, 助手 (60240941)
SUZUKI Yasuhiro Aichi Prefectural University, Faculty of Information Science and Technology, Ass, 文学部, 助教授 (70222065)
NAKAMURA Tsohio Nagoya University, Dating and Research Material Center, Associate Porfessor, 年代測定資料研究センター, 助教授 (10135387)
|
|---|
| Project Period (FY) |
1997 – 1998
|
| Keywords | Post-Glacial Age / Radiocarbon dating / Dendrochronology / Tephra / Mass movement / Paleoseismology / Tree-ring / Quaternary |
|---|
| Research Abstract |
In order to develop and popularize high-precision dating of significant geologic phenomena of the Post-Glacial age, we introduced a composite techniques of high-precision radiocarbon dating and relative dendrochronology. The first successful dating by wiggle matching, which gives better constraints on probabilty distribution of dendrocorrected radiocarbon age, was carried out for samples related with large mass-movment events and volcanic eruptions. For example, the age of the Kawago-daira tephra formarly dated as 2800 to 3300 yearsBP was precisely determined as 3120 Cal. years BP with a huge trunk sample of over 400 rings, 5 high-precision conventional dating with definite intervals of 75 to 100 years, and wiggle matching. For the relative dendrochronological analyses, we introduced very high resolution imaging of polished tree rings with 10000 dpi flatbed scanner. Scanned tree ring images are retouched and enlarged to make recognition and counting of the rings. This method of electronic tree ring analysis will improve the representability of tree-ring studies. On the other hand, recognition and dating techniques for paleo-earthquakes are refined through detailed analyses of lake deposits for chemical and physical signatures of faulting events that affected the lake environment. Once the horizon of disturbance is recognized, usual procedures for high-precision dating were., successfully applied. The investigators are propagating to the Japanese geologist the idea of high-precision dating and refinment of the dates for the advancement of precise chronology for all related sciences.
|
