Nuees ardentes of 22 November 1994 at Merapi volcano, Java, Indonesia
Nuees ardentes of 22 November 1994 at Merapi volcano, Java, Indonesia
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DOI：
10.1016/s0377-0273(00)00144-x
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发表时间：
2000-07-01
影响因子：
2.9
通讯作者：
Voight, B
中科院分区：
文献类型：
--
作者：
Abdurachman, EK;Bourdier, JL;Voight, B
1993年11月22日，与默拉皮火山圆顶坍塌有关的裸岩向西南偏南方向移动了6.5公里，总共积累了大约250万至300万立方米的沉积物。受损面积为9.5 km（2），被两个nuee ardente相、一个传统的“Merapi型”山谷填充块和灰排相和一个火山碎屑涌相所覆盖。近端沉积物反映了数十个nudes ardentes的堆积，具有许多附属流动单元。远源沉积物的组织较为简单，只有少数个别事件达到>3.5 km的距离。Turgo山北部的地层关系表明，浪涌沉积物是一种特别移动的nuees ardentes相，也沉积了通道块和灰流相。他们进一步表明，超出河道边缘的涌浪相与块灰排相底部局部发育的细粒子层横向相关。目击者报告表明，在博勇河远端的块状和灰排相的侵位可能是在Turgo村的涌浪相的破坏和沉积之后的一个短时间间隔内发生的。地层学与目击者报告雅阁。涌浪相是由稀释的涌浪流侵位的，从同一个圆顶塌陷的nuee ardente分离出来，作为一个单独的流动单元，随后侵位在Boyong山谷的远端块和灰存款。剥离发生在更高的海拔，可能在坡折处或以上，海拔约2000米。这种水流分离使浪涌电流能够在景观上抄近路，并使其存款就位，即使块和灰行继续在博勇海峡中曲折地向南移动。圆顶倒塌裸ardente活动形成了大部分的喷发，这是伴随着几乎没有显着的垂直峰会爆炸活动。(C)2000 Elsevier Science B.V.保留所有权利。
Nudes ardentes associated with dome collapse on 22 November 1993, at Merapi volcano traveled to the south-southwest as far as 6.5 km, and collectively accumulated roughly 2.5-3 million cubic meters of deposits. The damaged area comprises 9.5 km(2) and is covered by two nuee ardente facies, a conventional "Merapi-type", valley-fill block-and-ash Row facies and a pyroclastic surge facies, The proximal deposits reflect the accumulation of dozens of nudes ardentes, with many subsidiary flow units. The distal deposits are more simply organized, as only a few individual events reached to distances >3.5 km, The stratigraphic relationships north of Turgo hill indicate that the surge deposits are a facies of particularly mobile nuees ardentes that also deposited channeled block-and-ash flow facies. They further suggest that the surge facies beyond the channel margins correlate laterally with a finer-grained sublayer locally developed at the base of the block-and-ash Row facies. Eyewitness reports suggest that the emplacement of the block-and-ash Row facies in the distal part of the Boyong river may have followed, by a short time interval, the destruction and deposition of the surge facies at Turgo village, The stratigraphy is in accord with the eyewitness reports. The surge facies was emplaced by a dilute surge current, detached from the same dome-collapse nuee ardente that, as a separate flow unit, subsequently emplaced the distal block-and-ash deposit in the Boyong valley. The detachment occurred at higher elevations, likely at or above the slope break at about 2000 m elevation. This flow separation enabled the surge current to shortcut over the landscape and to emplace its deposit even as the block-and-ash Row continued its tortuous southward movement in the Boyong channel. Dome-collapse nude ardente activity formed the bulk of the eruption, which was accompanied by virtually no significant vertical summit explosive activity. (C) 2000 Elsevier Science B.V. All rights reserved.