Kilauea East Rift Zone Magmatism: an Episode 54 Perspective
Kilauea East Rift Zone Magmatism: an Episode 54 Perspective
复制标题
基拉韦厄东部裂谷带岩浆作用：第 54 集视角
DOI：
10.1093/petrology/egg048
复制
发表时间：
2003
影响因子：
3.9
通讯作者：
G. Meeker
中科院分区：
文献类型：
--
作者：
C. Thornber;C. Heliker;D. Sherrod;J. Kauahikaua;A. Miklius;P. Okubo;F. Trusdell;J. Budahn;W. Ridley;G. Meeker
1997年1月29日±30日，在活动基拉韦厄火山喷口上方1±4公里的纳帕陨石坑之下，持续稳定的熔岩流出被纳波火山口下方的浅层伸展作用短暂中断。一次长达23小时的喷发(第54集)是由1983年第1幕形成的与1963年和1968年早期裂谷带喷发形成的裂隙重叠或梯形形成的裂隙接踵而至的。1994±1999年喷发间隔期(包括第54幕)的综合地球物理和岩石学资料揭示了与裂谷带长期喷发有关的各种浅层岩浆条件。喷口附近的熔岩样本记录了喷发前岩浆的成分、温度和结晶度的很大范围。在斑晶±液体关系和基拉韦厄矿物温度计的支持下，导致第54幕的裂谷带伸展导致了近共熔岩浆与冷却到1100℃的离散岩浆体的混合。混合模型表明，自1963年至1968年以来隔离在纳帕陨石坑下的岩浆占第54幕期间喷发的混合混合的32±65%。地球物理测量支持开放系统岩浆沿着活动的东裂谷管道被动地移入沿着浅层伸展带的闭合系统裂谷储集层。第55幕早期的地球物理和岩石学数据证明，在该建筑物的岩浆补充过程中，与第54幕有关的岩浆逐渐冲刷。
On January 29±30, 1997, prolonged steady-state effusion of lava from Pu'u'O'o was briefly disrupted by shallow extension beneath Napau Crater, 1±4 km uprift of the active Kilauea vent. A 23-h-long eruption (episode 54) ensued from fissures that were overlapping or en echelon with eruptive fissures formed during episode 1 in 1983 and those of earlier rift zone eruptions in 1963 and 1968. Combined geophysical and petrologic data for the 1994±1999 eruptive interval, including episode 54, reveal a variety of shallow magmatic conditions that persist in association with prolonged rift zone eruption. Near-vent lava samples document a significant range in composition, temperature and crystallinity of pre-eruptive magma. As supported by phenocryst±liquid relations and Kilauea mineral thermometers established herein, the rift zone extension that led to episode 54 resulted in mixture of near-cotectic magma with discrete magma bodies cooled to 1100 C. Mixing models indicate that magmas isolated beneath Napau Crater since 1963 and 1968 constituted 32±65% of the hybrid mixtures erupted during episode 54. Geophysical measurements support passive displacement of open-system magma along the active east rift conduit into closed-system rift-reservoirs along a shallow zone of extension. Geophysical and petrologic data for early episode 55 document the gradual flushing of episode 54 related magma during magmatic recharge of the edifice.