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Study of snowball Earth events and rise of the atmospheric oxygen based on geologicalg survey of glacial sediments of the Paleoproterozoic

基于古元古代冰川沉积物地质调查的雪球地球事件与大气氧含量上升研究

基本信息

批准号：
14403004
负责人：
TAJIKA Eiichi
金额：
$ 8.32万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14403004/
关键词：
snowball Earth Proterozoic glacial sediments glaciation 氷河堆積物

项目摘要

In this project, we conducted geological surveys of the Huronian Supergroup, Ontario, in Canada to investigate environmental changes during the Paleoproterozoic (mainly, ca. 2450-2200 million years ago). We also conducted geological surveys of the Transvaal Supergroup in South Africa and the Snowy Pass Supergroup in USA for comparison. We took many rock samples from out crops and boring core samples, and analyzed them to investigate variations of color, grain size, chemical composition, and isotopic composition.We found that concentration of manganese above the uppermost diamictite of the Coleman Member in the Gowganda Formation. We also found that there is concentration of hematite which precedes the manganese anomaly. These evidences suggest that oxygen contents in the atmosphere and the surface ocean should have been high just after the Gowganda glaciation. Considering similar ages (ca. 2222 Ma), comparable amounts of manganese deposited per unit area, and sedimentary sequence (glacial diamictite -manganese and iron concentration -redbed) between the Huronian Supergroup in Canada and the Transvaal Supergroup in South Africa, we infer that these two areas may have recorded the same global events, namely, the snowball glaciation and the oxygen rise at ca. 2222 Ma.We also investigate variations of carbon isotopic composition of carbonates and organic carbon, mass independent fractionation of sulfur isotopes of pyrites, and paleomagnetism, based on the samples taken from the Huronian Supergroup and Snowy Pass Supergroup. We also study carbon cycle and paleoclimate change during the snowball Earth events using numerical models.

在这个项目中，我们对加拿大安大略的休伦超群进行了地质调查，以调查古元古代（主要是约1000年）的环境变化。2450-2200万年前）。我们还对南非德兰士瓦超群和美国雪道超群进行了地质调查，以供比较。我们从庄稼和钻孔取了许多岩石样品，分析了它们的颜色、粒度、化学成分和同位素组成的变化，发现在戈瓦甘达组科尔曼段最上部的杂岩之上有锰的富集。我们还发现，有集中的赤铁矿之前的锰异常。这些证据表明，在戈瓦甘达冰川作用后不久，大气和海洋表面的氧含量应该很高。考虑到相似的年龄（CA。2222 Ma）、单位面积锰沉积量相当、沉积序列（冰川杂屑岩-锰、铁富集-红层）等，推测这两个地区可能记录了相同的全球性事件，即约2222 Ma的雪球冰川作用和氧含量上升。2222 Ma。我们还研究了碳酸盐和有机碳的碳同位素组成的变化，黄铁矿的硫同位素的质量独立分馏，和古地磁，基于采取的样品从休伦超群和雪道超群。我们还使用数值模型研究了雪球地球事件期间的碳循环和古气候变化。

项目成果

期刊论文数量（13）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Analysis of carbon cycle system during the Neoproterozoic : Implication for snowball Earth events

新元古代碳循环系统分析：对雪球地球事件的影响

DOI：
发表时间：
2004
期刊：
Geophysical Monograph (The Extreme Proterozoic : Geology, Geochemistry, and Climate) 146
影响因子：
0
作者：
Tajika;E.
通讯作者：
E.

Eiichi Tajika: "Faint young Sun and the carbon cycle: Implication for the Proterozoic global glaciations"Earth and Planetary Science Letters. 214. 443-453 (2003)

Eiichi Tajika：“微弱的年轻太阳和碳循环：对元古代全球冰川作用的影响”地球与行星科学快报。

DOI：
发表时间：
期刊：
影响因子：
0
作者：
通讯作者：

A negative fold test on the Lorrain Formation of the Huronian Supergroup : Uncertainty on the paleolatitude of the Paleoproterozoic Gowganda glaciation and implications for the great oxygenation event

休伦超群洛林组的负褶皱检验：古元古代高甘达冰川古纬度的不确定性及其对大氧化事件的影响

DOI：
发表时间：
2005
期刊：
Earth and Planetary Science Letters (印刷中)
影响因子：
0
作者：
Isaac A.H.;Kirschvink;J.L.;Tajika;E.;Tada;R.;Hamano;Y.;Yamamoto;S.;K.Itagaki;Isaac A.Hilburn
通讯作者：
Isaac A.Hilburn