The pressure estimated by amphibole geobarometer in syenite and granil

角闪石地质气压计估算正长岩和花岗岩中的压力

• 批准号: 09640567
• 负责人: OBA Takanobu
• 金额: $ 1.98万
• 依托单位: Joetsu University of Education
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09640567/
• 关键词: Amphibole; Geobarometer; Granite; Syenite; Synthetic Experiment; 閃長岩

We attempt to estimate the pressure of amphibole-bearing syenites and granitic rocks in the range 600ﾟC -930ﾟC under a water pressure from 0.05GPa to 0.34GPa and oxygen fugacitied of the FMQ buffer. The stability limit curve of amphibole changes its P-T slope from positive at low pressure to negative at high pressure, and it intersects with a solidus of syenite and granite at two pressure points. We suggest that amphibole in syenite from the Yamato Mountains could have crystallized at pressres less than 0.3GPa (depth : -10 km), probably in a shallow crustal magma chamber.Hammarstrom and Zen (1986, 1992) proposed an empirical correlation between the estimated pressures of crystallization of calc-alkaline plutons and the total Al content of horublende. However, in the present experiments, the chemical composition of amphibole near solidus does not change. We reported that the pargasite content in amphibole increases with increasing temperature. If we compared with amphiboles synthesized at different temperatures, amphibole geobarometer is considerable uncertainty. We attempt the partitioning of Na, Al, Mg and Fe between amphibole and pyroxene.

我们试图在600°C -930 ﾟC的范围内估计含有闪石的蓝岩和花岗岩岩石在从0.05GPA到0.34GPA的水压下，并在FMQ缓冲液中散发出氧气。闪石的稳定性极限曲线将其P-T斜率从低压处的正变为高压下的负斜率，并在两个压力点上与蓝石和花岗岩的固体相交。我们建议，大约山脉的氰基中的闪石可能在小于0.3GPA（深度：-10 km）的压力组中结晶，可能是在浅层地壳岩浆室中。 Hammarsstrom and Zen（1986，1992）提出了钙碱性岩体结晶压力与Horublende的总含量之间的经验相关性。但是，在演讲实验中，固体附近的闪石的化学成分不会改变。我们报告说，闪石中的旁加岩含量随温度升高而增加。如果我们与在不同温度下合成的闪石进行比较，则两栖焦点测量表是不确定性的。我们尝试在闪石和辉石之间对Na，Al，Mg和Fe进行分区。

项目成果

Oba,T.: "Mineralogy of chondrule in Ouellan(Tanezroulft)meteorite." Bull.Joetsu Univ.Educ.17・2. 891-899 (1998)

Oba, T.：“Ouellan(Tanezroulft) 陨石中球粒的矿物学。”Bull.Joetsu Univ.Educ.17・2 (1998)。

吉川和男(共著): "群馬県中之条町に分布する関東ローム層中の大隈石-(Mg)" 群馬大学研究紀要. 47. 103-112 (1999)

Kazuo Yoshikawa（合著者）：“分布于群马县中之条町的关东壤土层中的奥麦石（Mg）”群马大学通报47. 103-112（1999）。

Oba,T.: "Chemistry of chromian spinel in picrite sillfrom Ogi,Sado island,Niigata Prefecture,Japan." Bull.Joetsu Univ.Educ.Vol.18,No2. 687-695 (1999)

Oba,T.：“来自日本新泻县佐渡岛小木的苦铁矿中铬尖晶石的化学成分。”

Gupta,A.K.: "Synthetic and natural rock systems." Allied Publishers LTD., 283 (1997)

Gupta,A.K.：“合成和天然岩石系统。”

Oba,T.: "Mineralogyof chondrulein OUellan(Tanezrouff)meteoite." Bull.Joefsu Univ.Educ.Vol.17,No2. 891-899 (1998)

Oba,T.：“OUellan（Tanezrouff）陨石球粒矿物学。”