Evolution and spread of the microbe accompanied paleoenvironmental fluctuation

古环境波动中微生物的进化和传播

• 批准号: 18540462
• 负责人: OGIHARA Shigenori
• 金额: $ 2.48万
• 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 (C)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18540462/
• 关键词: Anoxic oxidation of methane; Biomarker; Isoprenoid hydrocarbon; Cold seep carbonate; AMNE; Oceanic anoxic event; C; T境界; gem-アルカン

Atmospheric oxygen concentration in the Precambrian has been intensively studied for the past decade mainly because it is closely related to the environment of the Earth's surface, especially life evolution. Evolution models of atmospheric oxygen have been proposed based on physical and chemical analysis of paleosols, soils formed by ancient weathering, sulfur isotopes and so on. However, quantitative estimation of atmospheric oxygen levels have not been made between 2.8 and 1.8 billion years ago when atmospheric oxygen is considered to rise for the first time in the Earth's history. We developed a glove box which can control oxygen concentration and make us carry out mineral dissolution experiment We mimicked weathering in the glove box by reacting olivine with water, and examined Fe redistribution. The ratio of Fe oxidized and remaining in the system was 0.92 at 0.2 atm of partial pressure of oxygen (PO2) and 0.15 at 10(-4) atm. The results were well agreed with those observed in the paleosols. We, then made a model of Fe behavior during weathering considering the factors, dissolution rate of a mineral, Fe oxidation rate and groundwater flow rate. We derived a differential equation from the model and estimated the relationships between the concentration ratio of Fe(III) to Fe(II) in a weathering profile and PO2 quantitatively. The estimation has indicated that pH and groundwater flow rate affect the relationships but mineral dissolution rate or formation time of a weathering profile do not. The application of the model to paleosols has revealed that atmospheric oxygen rose gradually between 2.5 and 12.0 billion years ago.

在过去的十年中，对前寒武纪的大气氧浓度进行了深入研究，主要是因为它与地球表面的环境密切相关，尤其是生命的演变。已经提出了大气氧的进化模型，该模型是基于对古质的物理和化学分析，古代风化，硫同位素等形成的土壤的物理和化学分析。然而，在2.8亿到18亿年前，当大气氧在地球历史上首次上升时，大气氧水平的定量估计尚未进行。我们开发了一个可以控制氧气浓度的杂物盒，并使我们进行矿物溶解实验，我们通过与水反应橄榄石在手套箱中模仿风化，并检查了FE再分配。在0.2 atm的氧气（PO2）的0.2 atm和10（-4）atm时，在0.2 atm中，氧化和剩余的Fe氧化和剩余的比率为0.92。结果与在古溶质中观察到的结果很好地达成了一致。然后，考虑到矿物质的因素，Fe氧化速率和地下水流量的因素，溶解速率，我们在风化过程中制定了FE行为模型。我们从模型中得出一个微分方程，并估计了在风化曲线和PO2定量的情况下，Fe（III）与Fe（II）的浓度比之间的关系。估计表明，pH和地下水流量会影响关系，但是风化剖面的矿物质溶解速率或形成时间却没有。该模型在古化学中的应用表明，大气中的氧气逐渐在2.5至120亿年前。

项目成果

Highly branched isoprenoid hydrocarbon in the sediment of Lake Qinhai, Central China

中国中部青海湖沉积物中的高度支化类异戊二烯烃

• 发表时间: 2007
• 期刊: Res. Org. Geochem 22
• 作者: Ogihara;S.
• 通讯作者: S.

Acyclic hydrocarbons and ketones in cold-seep carbonates from central Hokkaido, northern Japan

日本北部北海道中部冷泉碳酸盐中的无环烃和酮

• 发表时间: 2008
• 期刊: Geochemical Journal 42(In press)
• 作者: Osaani;Y.;Sajeev;K.;Owada;M.;Keherapannala;K.V.W.;Prame;W.K.B.;Nakano;N. and Jayatileke;S.;S. Ogihara
• 通讯作者: S. Ogihara

The role of bacteria in the formation of phosphorite nodule from Late Pleistocene Kusu basin in northern Kyushu, Japan

日本九州北部晚更新世九州盆地细菌在磷矿结核形成中的作用

• 发表时间: 2006
• 作者: 大和田正明;佐藤彰;小山内康人;豊島剛志;白石和行;S. Ogihara
• 通讯作者: S. Ogihara

中国青海湖堆積物中の高分枝イソプレノイド炭化水素

中国青海湖沉积物中的高度支化类异戊二烯烃

• 发表时间: 2007
• 期刊: Research in Organic Geochemistry 22
• 作者: Owada;M.;荻原成騎
• 通讯作者: 荻原成騎

The biomarker composition of sediment core from Lake Quinhai, central Chine

中部昆海湖沉积物岩心生物标志物组成

• 发表时间: 2007
• 作者: Ogihara;S.
• 通讯作者: S.