Origins of the 1954–1960 Lavas, Kilauea Volcano, Hawaii: Major element constraints on shallow reservoir magmatic processes
Origins of the 1954–1960 Lavas, Kilauea Volcano, Hawaii: Major element constraints on shallow reservoir magmatic processes
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1954-1960 年夏威夷基拉韦厄火山熔岩的起源：浅层储层岩浆过程的主要元素限制
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
C. Stanley
中科院分区：
文献类型：
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作者：
J. Russell;C. Stanley
在1954-1960年期间，夏威夷的基拉韦厄火山喷发了四次：1954年(Halemaumau)和1959年(Kilauea Iki)发生了顶峰喷发，1955年和1960年在下东部裂谷带发生侧翼喷发。我们的分析表明，每次喷发的熔岩的化学成分仅通过观察到的斑晶组合的分馏和分选来联系。我们利用皮尔斯元素比值图作了以下观察和推论：1)每次喷发的守恒元素比值P/K的变化小于分析不确定度的预期。因此，我们不能否认这一假设：每一套熔岩代表着一套同岩浆成分。2)当四组熔岩分析中的每一组都被绘制在以Si/K和[0.5(Mg+Fe)+1.5Ca+2.75Na+0.25Al]/K为轴线的皮尔斯元素比值图上时，数据符合1.0的斜率。因此，我们不能否定这样的假设：每个数据集中的化学变化与OL±PL±AU的排序一致。3)4组熔岩的平均P/K值相同。因此，我们不能否认这个假设：1954-1960年的熔岩起源于同一批岩浆或具有相同P/K值的多个岩浆。最后，使用Kilauea数据套件(1959：SG-05)中的MOST镁玻璃分析，我们用基于热力学的计算模拟了分异路径。这些计算预测了一条液体下降线，这与从岩石和玻璃分析中推断的路径一致。因此，模拟为我们的假设提供了额外的检验，并证实了假设的分化模型。此外，这些计算表明，分化发生在不到0.3 Gpa的温度范围内，范围在100°C到150°C之间。
In the 1954–1960 period, Kilauea Volcano, Hawaii, erupted four times: summit eruptions occurred in 1954 (Halemaumau) and 1959 (Kilauea Iki) and flank eruptions occurred in the lower East rift zone in 1955 and 1960. Our analysis demonstrates that the chemical compositions of lavas from each eruption are related solely through fractionation and sorting of the observed phenocryst assemblages. We have used Pearce element ratio diagrams to make the following observations and inferences: 1) The conserved element ratio P/K for each eruption has less variance than is expected from analytical uncertainty. Thus, we cannot reject the hypothesis: Each set of lavas represents a comagmatic suite of compositions. 2) Where each of the four groups of lava analyses is plotted on a Pearce element ratio diagram with axes of Si/K and [0.5(Mg+Fe)+1.5Ca+2.75Na+0.25Al]/K, the data fit a slope of 1.0. Therefore, we cannot reject the hypothesis: The chemical variation in each data set is consistent with sorting of OL±PL±AU. 3) Each of the 4 groups of lavas has the same mean P/K ratio. As a result, we cannot reject the hypothesis: The 1954–1960 lavas originated from a single magma batch or several magmas with identical P/K values. Finally, using the most magnesian glass analysis in the Kilauea data suite (1959: SG-05), we have modelled the differentiation path with thermodynamic-based calculations. These calculations predict a liquid line of descent that is consistent with the path inferred from rock and glass analyses. Therefore, the simulations provide an additional test of our hypotheses and corroborate the postulated differentiation model. Additionally, these calculations suggest that differentiation took place at less than 0.3 Gpa and extended over a temperature range of between 100°C and 150°C.