Project/Area Number |
25400495
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Stratigraphy/Paleontology
|
Research Institution | University of Tsukuba |
Principal Investigator |
|
Co-Investigator(Kenkyū-buntansha) |
MARUOKA Teruyuki 筑波大学, 生命環境系, 准教授 (80400646)
SASHIDA Katsuo 筑波大学, 生命環境系, 教授 (60134201)
|
Project Period (FY) |
2013-04-01 – 2016-03-31
|
Project Status |
Completed (Fiscal Year 2015)
|
Budget Amount *help |
¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000)
Fiscal Year 2015: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2014: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Fiscal Year 2013: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
|
Keywords | 生層序 / 炭素同位体 / 硫黄同位体 / 古環境 / オルドビス紀 / 地球化学 / 岩相層序 / 地球化学的分析 / シルル紀 / マレーシア / コノドント / 筆石 / 同位体 |
Outline of Final Research Achievements |
This study reconstructs an environmental change during the latest Ordovician to earliest Silurian time, when a mass extinction occurred, based on the paleontological, sedimentological, and geochemical analyses. The end-Ordovician global cooling is widely accepted as being the cause of the extinction. The sedimentological study and the carbon isotopic analysis show that this study area also went through a cooling and regression events in the Late Ordovician. The carbon/sulfur ratio reveals that recovery of the environment took a relatively long time and that the climate was gradually getting warm with a cyclic alternation of warm and cool periods throughout the Early Silurian. The sedimentological and micropaleontological data also support this conclusion.
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