Timescales from magma mixing to eruption in alkaline volcanism in the Eifel volcanic fields, western Germany
Timescales from magma mixing to eruption in alkaline volcanism in the Eifel volcanic fields, western Germany
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德国西部埃菲尔火山田碱性火山活动从岩浆混合到喷发的时间尺度
DOI：
10.1007/s00410-020-01715-y
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发表时间：
2020
影响因子：
3.5
通讯作者：
G. Wörner
中科院分区：
文献类型：
--
作者：
C. Sundermeyer;Jochen Gätjen;Lena Weimann;G. Wörner
对成分分带的Laacher See Tephra矿床的最终镁铁质喷发产物中的橄榄石晶体中的扩散剖面进行了测量，以确定Laacher See火山(12.9 KYR)喷发之前的补给和喷发触发事件。这些产物代表了储层底部声岩和侵入玄武岩的混合产物，可能与喷发事件有关。此外，还分析了来自10个玄武质玄武岩圆锥体和MAAR矿床(东艾菲尔)和两个霞石(西艾菲尔)中的橄榄石晶体，以限制第四纪玄武岩岩浆中橄榄石的历史。来自Laacher的橄榄石晶体看到混合体的核心成分(Fo83-89)不同，并显示出与东艾菲尔玄武岩中的橄榄石相反的带状地幔，具有高Fo87.8-89，这些橄榄石是在附近较老的天花锥中喷发的。在晶体边缘，杂交种中的橄榄石发育成正常的带状过度生长(FO86.5-87.5)。东埃菲尔玄武岩中的橄榄石具有相似的分带和核心成分(FO80-88)，但镁橄榄质地幔较少(FO83-88)，这表明这些玄武岩的原始程度低于那些补充Laacher See储层的玄武岩(>； Fo89)。西艾菲尔霞石中的橄榄石显示出与拉切尔(Foacher See)相似的地幔(Fo87.5-90)，但具有正常的分带和高Fo核(Fo88-92)。这表明，Laacher See杂交岩中的橄榄石是在玄武岩与声石杂交之前被来自较老堆积物的接近原生的玄武岩夹带的。扩散模拟表明，从夹带到喷发之间的最大时间尺度为30-400天，与从玄武质斯科石锥体中计算出的橄榄石的时间尺度(10-400天)相当。
Diffusion profiles in olivine crystals from the final mafic eruption products of the compositionally zoned Laacher See tephra deposit were measured to identify recharge and eruption-triggering events prior to the eruption of the Laacher See volcano (12.9 kyr). These products represent the hybrids of mixing between phonolite and intruding basanite at the bottom of the reservoir, which is likely related to the eruption-triggering event. Additionally, olivine crystals from ten basanitic scoria cones and maar deposits (East Eifel) and two nephelinites (West Eifel) were analyzed to constrain histories of olivine in Quaternary basanite magmas. Olivine crystals from the Laacher See hybrids vary in core composition (Fo83–89) and show reversely zoned mantles with high Fo87.8–89 compared to olivine in East Eifel basanites erupted in nearby, older scoria cones. Towards the crystal margin, olivine in the hybrids develop a normally zoned overgrowth (Fo86.5–87.5). Olivine from East Eifel basanites show similar zonation and core compositions (Fo80–88) but have less forsteritic mantles (Fo83–88) indicating that these basanites are less primitive than those recharging the Laacher See reservoir (> Fo89). Olivine in the West Eifel nephelinites show mantles similar to those from Laacher See (Fo87.5–90), but have normal zoning and high-Fo cores (Fo88–92). This indicates that olivine in the Laacher See hybrids were entrained by a near-primary basanite from older cumulates just before hybridization of the basanite with the phonolite. Diffusion modeling indicates maximum timescales between entrainment and eruption of Laacher See of 30–400 days that are comparable to those calculated for olivine from basanitic scoria cones (10–400 days).
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影响因子：
5.3
作者：
K. Lynn;T. Shea;Michael O. Garcia;F. Costa;M. Norman
通讯作者：
K. Lynn;T. Shea;Michael O. Garcia;F. Costa;M. Norman
影响因子：
3.1
作者：
K. Lynn;T. Shea;Michael O. Garcia
通讯作者：
K. Lynn;T. Shea;Michael O. Garcia
改进了 RESET 晶格中重要的晚第四纪欧洲火山灰地层的年龄估计
影响因子：
4
作者：
Bronk Ramsey C
通讯作者：
Bronk Ramsey C
破解橄榄石分区密码：区分晶体生长和扩散
影响因子：
5.8
作者：
Shea, Thomas;Lynn, Kendra J.;Garcia, Michael O.
通讯作者：
Garcia, Michael O.
冰岛地下快速穿地壳岩浆运动
影响因子：
18.3
作者：
Mutch E
通讯作者：
Mutch E