Petrogenesis and volcanology of anorogenic rhyolites: a special issue dedicated to Bill Bonnichsen
Petrogenesis and volcanology of anorogenic rhyolites: a special issue dedicated to Bill Bonnichsen
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非造山流纹岩的岩石成因和火山学：比尔·邦尼克森 (Bill Bonnichsen) 特刊
DOI：
10.1007/s00445-007-0137-2
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发表时间：
2007
影响因子：
3.5
通讯作者：
W. Leeman
中科院分区：
文献类型：
--
作者：
M. McCurry;E. H. Christiansen;W. Leeman
大体积高温火山岩的出现显然局限于大陆地区，是长期以来向大陆地壳输入大量能量的表现。在美国西部，这种岩浆作用主要发生在新生代大盆地和外佩科斯（西德克萨斯州）火山区的伸展环境中。在晚新生代蛇河平原-黄石省特别多产，形成了穿越爱达荷州南部的时间海侵“热点”轨迹，在那里，流纹岩被挤压成大型熔岩流，甚至更大的熔结凝灰岩。个别喷发的范围至少为100 km 3的熔岩流和多达3,000 km 3的熔结凝灰岩。累积量的岩浆生产可能超过10 - 5公里3，使这个省的地球上最多产的流纹岩喷流。这些流纹岩的特征是岩浆温度高（有时超过1，000 °C），无水斑晶组合，低氧逸度和A型微量元素化学。在所有这些方面，“非造山”流纹与“造山”背景下的岩浆形成鲜明对比（即，大盆地和科罗拉多高原的会聚边缘和中新生代钙碱性岩浆，包括
The occurrence of large volume, high-temperature silicic volcanic rocks is apparently confined to continental regions and is a manifestation of significant energy input into the continental crust over extended time periods. In the western United States, such magmatism occurs predominantly in extensional settings in the Cenozoic Great Basin and TransPecos (west Texas) volcanic provinces. It is particularly prolific in the late Cenozoic Snake River Plain-Yellowstone province that forms a time-transgressive ‘hot spot’ track across southern Idaho, where rhyolites were extruded as large lava flows and even larger ignimbrites. Volumes of individual eruptions range up to at least 100 km 3 for the lava flows and to as much as 3,000 km 3 for the ignimbrites. Cumulative volumes of silicic magma produced likely exceed 10 5 km 3 , making this province one of the most prolific rhyolite outpourings on Earth. These rhyolites are characterized by high magmatic temperatures (sometimes exceeding 1,000°C), anhydrous phenocryst assemblages, low oxygen fugacities, and A-type trace element chemistry. In all these respects the “anorogenic” rhyolites contrast sharply with silicic magmas from “orogenenic” settings (i.e., convergent margins and mid-Cenozoic calcalkaline silicic magmas of the Great Basin and Colorado Plateau including