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The mass estimation of volatile emission during 1199-1200 AD eruption of Baitoushan volcano and its significance 总被引：2，自引：1，他引：2
On the basis of the study of volcanic products during 1199-1200AD eruption of Baitou Mountain (Baitoushan), the released volatile content was estimated by comparing Cl, F, S, H2O concentrations of undegassed glass inclusions with those of degassed matrix glasses. The calculations show that volatile yields, released from the melt, are 109.88×106 ton of HCl, 196.80×106 ton of HF, 1477.84×106 ton of H2O, 23.14×106 ton of SO2, which could have formed 35.43×106 ton of H2SO4 aerosol in the atmosphere. They could have substantial effect on paleoclimate and paleo-environment. 相似文献
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吉林省白头山火山岩的岩石学研究 总被引：7，自引：1，他引：6
白头山火山位于吉林省东部,主要由一套粗面岩—钠闪碱流岩组成。岩石中长石斑晶的成分表现出逐步富Or的趋势。单斜辉石早期向富Fe,而晚期表现为向富NaFe3+Si2O6的方向演化。矿物成分变化规律的研究揭示了白头山火山岩与长白山玄武岩之间的成因联系。岩石主要元素化学成分在过碱性酸性岩系统的Q—Ab—Or相图及SiO2—Al2O2—Na2O+K2O图上的投影,表明了白头山火山岩的演化主要是受碱性长石的分离结晶所控制,但在从粗面岩到石英粗面岩的演化过程中涉及少量斜长石组分的分离结晶。用最小二乘法对白头山火山岩的成因及其演化过程进行了定量模拟。所得结果与岩相学和岩石化学的分析结果相吻合,证实了白头山火山岩是由长白山玄武岩分离结晶形成的成因假说。根据热力学计算和过碱性岩石的高温高压实验,推测岩浆形成温度分别为1074—928℃,形成压力约在2-3kb。 相似文献
3.
吉林省白头山火山岩的微量元素及其岩石学意义 总被引：2，自引：0，他引：2
白头山火山岩中含有一套粗面岩—钠碱流岩,与下伏的长白山玄武岩组成一个岩石系列。在白头山火山岩中,REE、Zn、Zr等元素十分富集,而过渡元素及Sr、Ba等元素极其贫 化。REE配分具明显的Eu负异常,许多不相容元素在岩石系列中表现出良好的线性关系。依据微量元素行为的数学模式对这些特征进行定性分析和定量模拟,其结果表明白头山火山岩是由长白山玄武岩岩浆经结晶分异形成的。 相似文献
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Volatile emission during the eruption of Baitoushan Volcano (China/North Korea) ca. 969 AD 总被引：33，自引：1，他引：32
3 [magma volume (DRE): 24 ± 5 km3]. The main phase (ca. 95 vol.%) is represented by comenditic tephra deposited dominantly as widespread fallout blankets and
proximal ignimbrites. The eruption column is estimated to have reached ca. 25 km and thus entered the stratosphere. A late
phase (5 vol.%) is represented by trachyte emplaced chiefly as moderately welded ignimbrites. The comendites contain ∼ 3,
and the trachytes 10–20 vol.% phenocrysts, mainly anorthoclase, hedenbergite, and fayalite. Primary glassy melt inclusions
with no signs of leakage were found only in phenocrysts in the comenditic tephra, whereas those in phenocrysts in the trachytes
are devitrified. The comendite magma is interpreted to have been generated by fractional crystallization from a trachyte magma
represented by melt inclusions in the phenocrysts in the comendite tephra. The mass of volatiles emitted to the atmosphere
during the eruption was estimated using the petrologic method. The average H2O concentration of the comenditic matrix glass is 1.5 wt.% (probably largely secondary) and of the corresponding melt inclusions
∼ 5.2 wt.%. Melt inclusions in feldspar and quartz present the highest halogen concentrations with a calculated average for
chlorine of 4762 ppm and for fluorine of 4294 ppm. The comenditic matrix glasses are represented by a fluorine-rich (3992 ppm
F) and fluorine-poor group (2431 ppm F), averaging 3853 ppm for chlorine. Only 20% of all sulfur analyses of the comenditic
matrix glasses and melt inclusions are above the detection limit of ≥ 250 ppm S. The difference between pre- and post-eruptive
concentration of H2O is at least 3.7 ± 0.6 wt.% H2O taking into consideration re-hydration of the matrix glass and possible leakage of melt inclusions. The difference between
pre- and post-eruptive concentrations of the halogens amounts to 909 ± 90 ppm Cl, and 1863 ± 280 ppm and 302 ± 40 ppm F. The
difference for S was estimated based on the average of the maximum S concentrations in the melt inclusions (455 ppm S) and
the detection limit, resulting in 205 ± 40 ppm S. The calculated mass of volatiles injected into the atmosphere, based on
the erupted magma volume and volatile data, is 1796 ± 453 megatons for H2O, 45 ± 10 megatons for chlorine, 42 ± 11 megatons for fluorine, and 2 ± 0.6 megatons for sulfur. The 969 ± 20 AD eruption
of Baitoushan Volcano, one of the largest eruptions of the past 2000 years, is thought to have had a substantial but possibly
short-lived effect on climate.
Received: 25 July 1998 / Accepted: 8 September 1999 相似文献
5.
Zhengfu?GuoEmail author Jiaqi?Liu Shuzhen?Sui Qiang?Liu Huaiyu?He Yunyan?Ni 《中国科学D辑(英文版)》2002,45(6):530-539
On the basis of the study of volcanic products during 1199–1200AD eruption of Baitou Mountain (Baitoushan), the released volatile
content was estimated by comparing Cl, F, S, H2O concentrations of undegassed glass inclusions with those of degassed matrix glasses. The calculations show that volatile
yields, released from the melt, are 109.88 × 106 ton of HCl, 196.80 × 106 ton of HF, 1477.84 × 106 ton of H2O, 23.14 × 106 ton of SO2, which could have formed 35.43 x106 ton of H2SO4 aerosol in the atmosphere. They could have substantial effect on paleoclimate and paleo-environment. 相似文献
6.
白头山铷矿床是甘肃北山地区新近发现的典型花岗伟晶岩脉型铷稀有金属矿床,以该矿床为研究对象,开展了土壤地球化学测量方法技术研究。初步确定花岗伟晶岩脉型铷稀有金属矿床的岩石和土壤中的通用指示元素组合为Rb、Be、Bi、Tl、Li、K 2O;北山地区勘查铷稀有金属矿床的土壤地球化学测量的最佳采样粒级为-4~20目,最佳采样层位为残积层。试点测量结果表明,研究确定的土壤地球化学测量方法可以完整地圈定已知的铷矿化范围,迅速缩小找矿靶区,为后续异常查证等工作布署提供准确的地球化学依据,为北山地区找寻铷稀有金属矿产提供了一种新的方法技术。同时试点测量在已知矿区外围发现了新的具有找铷矿前景的靶区,有望获得新的找矿进展,为同类地区寻找铷稀有金属矿产提供了示范。 相似文献
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