Isotopic Study on Formation and Evolution of the Continental Crust

陆壳形成与演化的同位素研究

• 批准号: 07404052
• 负责人: SHIMIZU Hiroshi
• 金额: $ 2.11万
• 依托单位: KUMAMOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07404052/
• 关键词: La-Ce system; Sm-Nd system; REE pattern; Continental Crust; Kamiaso conglomerate; Pilbara Block; Precambrian; Chert; U-Pb年代; 黒瀬川帯; ジルコン; 先カンブリア紀; Rb-Sr年代; 海洋性推積物; Sm-Nd同位体系; La-Ce同位体系; 希土類元素パターン; ピルバラ地塊; 秩父帯

Formation and evolution of the continental crust were isotopically and geochemically studied. Some of the resuIts are summarized as follows.1.Neodymium and cerium isotopic ratios, rare earth element (REE) abundances and major element compositions were determined for Precambrian orthogneiss and granite clasts in the Jurassic Kamiaso conglomerate from central Japan. Sm-Nd data on these rocks give an age of (2.07(]SY.+-。[)0.06) Ga (2sigma) with epsilon<@D2Nd@>D2 (2.07Ga)=-1.9(]SY.+-。[)0.4. The Sm-Nd age is in accordance with the Rb-Sr whole rock age of 2.05 Ga for quartzo-feldsparthic gneiss clasts by Shibata and Adachi (1974), confirming that the age of ca.2.05 Ga indicates the time of formation age of the original granitic rocks. The initial value of epsilon<@D2Nd@>D2 (2.07Ga)=-1.9 shows slightly enriched or chondritic feature for source of origibal granitic rocks at 2.07 Ga.2.Isotopic data of Sm-Nd, La-Ce and Rb-Sr systems, REE abundances and major element compositions are reported for … More the Archean Marble Bar Chert from the Towers Formation of the Salgash Subgroup, Warrawoona Group, Pilbara Block, Western Australia. The Marble Bar Chert records two Sm-Nd ages ; 3.2(]SY.+-。[)0.3 Ga for red (or black) and white banded cherts and 2.5(]SY.+-。[)0.2 Gafor yellowish gray cherts. The older age of 3.2(]SY.+-。[)0.3 Ga can be regarded as the formation time of the banded cherts. On the other hand, the younger age of 2.5(]SY.+-。[)0.2 Ga for the yellowish gray cherts is thought to reflect the time of later thermal events and the cherts do not retain their original chemical features. The 3.2 Ga Sm-Nd age for the Marble Bar banded cherts is the first Archean record obtained for the Archean cherts ; their initial epsilon<@D2Nd@>D2 value of +1.0(]SY.+-。[)3.0 holds the original nature at their formation without severe geochemical disturbance.3.REE abundances, Sr isotopic data and major element compositions are reported for the Permian and Triassic cherts from Kuma and Saiki areas in the Southern Chichibu (Sambosan) terrane, the Outer Zone of Southwest Japan. Our geochemical and isotopic data of the Sambosan cherts suggest a change from ocean-basin floor deposition for the Permian to hemi-pelagic for the Triassic cherts. Less

连续地壳的形成和演变是同位素和地球化学研究的。其中一些重置的总结如下。1。Neodymium和同位素比率，稀土元素（REE）抽象和主要元素组成，用于侏罗纪Kamiaso Contlomator的前寒武纪正牙和花岗岩经典。这些岩石上的SM-ND数据给出了（2.07（]SY。+ - 。[）0.06）ga（2sigma），带有Epsilon <@d2nd@> d2（2.07ga）= - 1.9（]SY。+ - 。[）0.4。 SM-ND年龄与Shibata和Adachi（1974）的石英 - 费尔德斯普雷斯群众片术分类者的RB-SR全岩年龄一致，证明了CA.2.05 GA的年龄表明原始花岗岩岩石的形成时代的年龄。 Epsilon <@d2nd@> d2（2.07ga）= - 1.9的初始值显示出略有丰富或软骨的特征，用于2.07 ga.2.的起源花岗岩岩石来源。西澳大利亚州Pilbara Block的Warrawoona集团。大理石酒吧Chert记录了两个SM-ND年龄； 3.2（]sy。+ - 。[）0.3 ga，红色（或黑色）和白色带状的cherts和2.5（]sy。+ - 。[）0.2 ga，用于黄色灰色cherts。 3.2（]SY。+ - 。[）0.3 ga的年龄可以将其视为带状切口的形成时间。另一方面，淡黄色灰色的年龄为2.5（]SY。+ - 。[）0.2 GA被认为反映了以后的热事件的时间，而Cherts则没有保留其原始化学特征。大理石条带Cherts的3.2 GA SM-ND年龄是Archean Cherts获得的第一张纪录。 their initial epsilon<@D2Nd@>D2 value of +1.0(]SY.+-.[)3.0 holds the original nature at their formation without severe geochemical disorder.3.REE abstractions, Sr isotopic data and major element compositions are reported for the Permian and Triassic cherts from Kuma and Saiki areas in the Southern Chichibu (Sambosan) terrane, the Outer Zone of Southwest Japan.我们的Sambosan Cherts的地球化学和同位素数据表明，二叠纪的海洋巴斯蛋白地板沉积发生了变化，转变为三叠纪cherts的Hemi-Pelagic。较少的

项目成果

M.Toriumi, K.Kawamura, I.Ohno, M.Akaogi, T.Kawasaki and H.Shimizu: Earth and Planetary Material Science. Iwanami, 292 (1996)

M.Toriumi、K.Kawamura、I.Ohno、M.Akaogi、T.Kawasaki 和 H.Shimizu：地球与行星材料科学。

T.Saito, H.Shimizu and A.Masuda: "Experimental study of major and trace element partitoning among olivine,metallic phase and silicate melt using chondrite as starting material:implication for V-shaped REE patterns of the pallasite meteorites" Geochemical

T.Saito、H.Shimizu 和 A.Masuda：“以球粒陨石为起始材料的橄榄石、金属相和硅酸盐熔体之间主量和微量元素分配的实验研究：对橄榄石陨石 V 形 REE 模式的启示”地球化学

T.Akagi, S.Nakai, H.Shimizu and A.Masuda: "Constraint on the geochemical stage causing tetrad effect in kimuraite:comparative studies on kimuraite and its related rocks,from REE pattern and Nd isotope ratio" Geochemical Journal. 30. 139-148 (1996)

T.Akagi、S.Nakai、H.Shimizu 和 A.Masuda：“对金村石中引起四分体效应的地球化学阶段的限制：从 REE 模式和 Nd 同位素比对金村石及其相关岩石的比较研究”《地球化学杂志》。

Masayo Minami: "Two Archean Sm-Nd ages of 3.2 and 2.5 Ga for the Marble Bar chert,Warrawoona Group,Pilbara Block,Western Australia" Geochemical Journal. 29. 347-362 (1995)

Masayo Minami：“西澳大利亚皮尔巴拉地块 Warrawoona 群 Marble Bar 燧石的两个太古代 Sm-Nd 年龄分别为 3.2 和 2.5 Ga”《地球化学杂志》。

K.Suzuki, H.Shimizu AND A.Masuda: "Re-Os dating of molybdenite from ore deposits in Japan ; implication for closure temperature of Re-Os system for molybdenite and cooling history of molybdenum ore deposits" Geochimica et Cosmochimica. Acta, 60. 3151-3159

K.Suzuki、H.Shimizu 和 A.Masuda：“日本矿床中辉钼矿的 Re-Os 定年；辉钼矿 Re-Os 系统闭合温度的含义以及钼矿床的冷却历史”Geochimica et Cosmochimica。