Following magma: The pathway of silicic magmas from extraction to storage during an ignimbrite flare-up, Taupō Volcanic Zone, New Zealand
Following magma: The pathway of silicic magmas from extraction to storage during an ignimbrite flare-up, Taupō Volcanic Zone, New Zealand
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跟随岩浆：在新西兰陶普火山区火成岩爆发期间，硅质岩浆从提取到储存的路径
DOI：
10.1016/j.epsl.2023.118053
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发表时间：
2023
影响因子：
5.3
通讯作者：
Gualda, Guilherme A.R.
中科院分区：
文献类型：
--
作者：
Smithies, Sarah L.;Harmon, Lydia J.;Allen, Sydney M.;Gravley, Darren M.;Gualda, Guilherme A.R.
非常大的火山岩浆系统可以产生数万至数千立方公里的非常演化的流纹岩岩浆，这些岩浆在破火山口形成事件中喷发。这些岩浆系统可能包含多个岩浆泥体，从中提取和储存可喷发的贫结晶岩浆。我们研究的压力，岩浆提取的糊状物和存储的可喷发的岩浆体从七个破火山口形成的喷发在中央陶波火山区，新西兰，在350万年至240万年的熔结凝灰岩耀斑。对于第一次，我们使用流纹岩熔体地质压力计算提取和存储压力相同的浮石碎屑（代表岩浆包裹），揭示了每次喷发是由多个，成分不同，糊状和可喷发的岩浆体。一些可喷发的物体与岩浆泥连续储存;但是，平均而言，我们的计算显示，可喷发的岩浆的单个包裹储存在比其提取深度浅2.6公里的地方，这表明岩浆在喷发前的积累中迁移了相当大的垂直距离。闪焰包括三种不同的岩浆系统几何形态：（1）成熟型，多个可喷发岩浆体在地壳浅部相邻（2）浅部可喷发岩浆体与浅部糊状堆积体直接接触的“糊状模型”型;（3）“垂直离散”型，可喷发的岩浆体储存在不同的深度，也可能从单独的泥质体中提取。耀斑开始于一个“成熟”型系统，其中有非常大的（>2200 km 3岩浆）Whakamaru群喷发。在华卡玛鲁火山之后，喷发规模较小（喷发50 - 150立方千米的岩浆），最初有很深的“垂直离散”的岩浆系统。随后的爆发揭示了一个新系统的垂直扩展，直到最后一次爆发（Ohakuri）有一个“成熟”型组织。这一系列的耀斑喷发暗示了非常大的岩浆系统如何在地质学上很短的时间内（100 kyrs）从一个垂直离散的岩浆体拼凑成一个成熟的岩浆系统，浅存储区和成分不均匀的岩浆泥下面空间和垂直成熟。
Very large silicic magma systems can generate tens to thousands of cubic kilometres of very evolved, rhyolitic magmas that erupt in caldera-forming events. These magma systems may incorporate multiple bodies of magma mush, from which eruptible, crystal-poor magma is extracted and stored. We examine the pressure of magma extraction from the mush and storage of eruptible magma bodies from seven caldera-forming eruptions in the central Taupō Volcanic Zone, New Zealand, during a 350 ka to 240 ka ignimbrite flare-up. For the first time, we use rhyolite-MELTS geobarometry to calculate extraction and storage pressures for the same pumice clasts (representing magma parcels), revealing that each eruption was fed by multiple, compositionally distinct, mush and eruptible magma bodies. Some of the eruptible bodies were stored contiguously with the magma mush; but, on average, our calculations reveal that individual parcels of eruptible magma were stored ∼6 km shallower than their extraction depths, demonstrating that magmas migrate an appreciable vertical distance in the build-up to eruption. The flare-up includes three different geometries of magmatic system: 1) a “mature” type in which multiple eruptible magma bodies sit adjacent to each other in the shallow crust (∼100 MPa) and are in contact with the top of a vertically extensive, heterogeneous mush system; 2) a “mush model” type in which a shallow eruptible magma body is directly in contact with a shallow mushy cumulate; and 3) a “vertically discretised” type in which eruptible magma bodies are stored at different depths and may also be extracted from separate mush bodies. The flare-up began with a “mature” type system, with the very large (>2200 km3magma) Whakamaru Group eruptions. Following Whakamaru, the eruptions were smaller (erupting 50 – 150 km3magma), and initially had deep, “vertically discretised” magma systems. The subsequent eruptions reveal the vertical expansion of a new system, until the last eruption (Ohakuri) had a “mature”-type organisation. This sequence of flare-up eruptions hints at how very large silicic magma systems can spatially and vertically mature over a geologically short timeframe (∼100 kyrs) from a patchwork of vertically discretised magma bodies to a mature magma system with a shallow storage zone and compositionally heterogeneous magma mush beneath.
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主教凝灰岩：喷发地层学的新见解
DOI：
--
发表时间：
1997
期刊：
The Journal of geology
影响因子：
--
作者：
C. Wilson;W. Hildreth
通讯作者：
W. Hildreth
数字共享@密歇根理工大学 数字共享@密歇根理工大学 攀登地壳阶梯：岩浆储存深度演化 攀登地壳阶梯：火山爆发期间岩浆储存深度演化
DOI：
--
发表时间：
--
期刊：
影响因子：
--
作者：
A. Boin;M. van Eeten
通讯作者：
M. van Eeten
影响因子：
3.9
作者：
Blundy J
通讯作者：
Blundy J
影响因子：
3.7
作者：
Gualda GA;Pamukcu AS;Ghiorso MS;Anderson AT Jr;Sutton SR;Rivers ML
通讯作者：
Rivers ML
智利大体积 Cardones Ignimbrite 的岩石成因；复杂岩浆-糊状系统的发育和不稳定
影响因子：
3.9
作者：
M. E. van Zalinge;R. Sparks;J. Blundy
通讯作者：
J. Blundy