Hawaii bibliographic database     

Thomas L. Wright  Taeko Jane Takahashi 《Bulletin of Volcanology》1998,59(4):276-280

 The Hawaii bibliographic database has been created to contain all of the literature, from 1779 to the present, pertinent to the volcanological history of the Hawaiian-Emperor volcanic chain. References are entered in a PC- and Macintosh-compatible EndNote Plus bibliographic database with keywords and abstracts or (if no abstract) with annotations as to content. Keywords emphasize location, discipline, process, identification of new chemical data or age determinations, and type of publication. The database is updated approximately three times a year and is available to upload from an ftp site. The bibliography contained 8460 references at the time this paper was submitted for publication. Use of the database greatly enhances the power and completeness of library searches for anyone interested in Hawaiian volcanism. Received: 1 June 1997 / Accepted: 17 September 1997  相似文献   

腾冲火山岩年龄问题评述   总被引：1，自引：0，他引：1  

上官德树 《云南地质》2012,(3):391-395

腾冲火山及火山岩是国内新近纪火山及其喷发物九大分布区之一,研究程度较广较深,喷发序列岩石定岩及年龄值资料丰富,综合评述并指出今后研究方向。  相似文献   

Precursory seismicity of the 1994 eruption of Popocatépetl Volcano,Central Mexico   总被引：1，自引：1，他引：0  

Servando De la Cruz-Reyna  Izumi Yokoyama  Alicia Martínez-Bringas  Esteban Ramos 《Bulletin of Volcanology》2008,70(6):753-767

Popocatépetl Volcano is located in the central Mexican Volcanic Belt, within a densely populated region inhabited by over 20 million people. The eruptive history of this volcano indicates that it is capable of producing a wide range of eruptions, including Plinian events. After nearly 70 years of quiescence, Popocatépetl reawakened in December 21, 1994. The eruptive activity has continued up until the date of this submission and has been characterized by a succession of lava dome growth-and-destruction episodes, similar to events that have apparently been typical for Popocatépetl since the fourteenth century. In this regime, the episodes of effusive and moderately explosive activity alternate with long periods of almost total quiescence. In this paper we analyze five years of volcano-tectonic seismicity preceding the initial eruption of the current episode. The evolution of the V-T seismicity shows four distinct stages, which we interpret in terms of the internal processes which precede an eruption after a long period of quiescence. The thermal effects of a magma intrusion at depth, the fracturing related to the slow development of magma-related fluid pathways, the concentration of stress causing a protracted acceleration of this process, and a final relaxation or redistribution of the stress shortly before the initial eruption are reflected in the rates of V-T seismic energy release. A hindsight analysis of this activity shows that the acceleration of the seismicity in the third stage asymptotically forecast the time of the eruption. The total seismic energy release needed to produce an eruption after a long period of quiescence is related to the volume of rock that must be fractured so imposing a characteristic threshold limit for polygenetic volcanoes, limit that was reached by Popocatépetl before the eruption.  相似文献   

New physical characterization of the Fontana Lapilli basaltic Plinian eruption,Nicaragua   总被引：1，自引：1，他引：0  

L. Costantini  C. Bonadonna  B. F. Houghton  H. Wehrmann 《Bulletin of Volcanology》2009,71(3):337-355

The Fontana Lapilli deposit was erupted in the late Pleistocene from a vent, or multiple vents, located near Masaya volcano (Nicaragua) and is the product of one of the largest basaltic Plinian eruptions studied so far. This eruption evolved from an initial sequence of fluctuating fountain-like events and moderately explosive pulses to a sustained Plinian episode depositing fall beds of highly vesicular basaltic-andesite scoria (SiO₂ > 53 wt%). Samples show unimodal grain size distribution and a moderate sorting that are uniform in time. The juvenile component predominates (> 96 wt%) and consists of vesicular clasts with both sub-angular and fluidal, elongated shapes. We obtain a maximum plume height of 32 km and an associated mass eruption rate of 1.4 × 10⁸ kg s⁻¹ for the Plinian phase. Estimates of erupted volume are strongly sensitive to the technique used for the calculation and to the distribution of field data. Our best estimate for the erupted volume of the majority of the climactic Plinian phase is between 2.9 and 3.8 km³ and was obtained by applying a power-law fitting technique with different integration limits. The estimated eruption duration varies between 4 and 6 h. Marine-core data confirm that the tephra thinning is better fitted by a power-law than by an exponential trend.  相似文献   

熔体包裹体对长白山天池火山千年大喷发的指示意义   总被引：2，自引：2，他引：0  

李霓  樊祺诚  孙谦  盘晓东 《岩石学报》2008,24(11):2604-2614

长白山天池火山在全新世曾有过几次喷发,其中距今约1000年发生过大规模布里尼式爆炸喷发（即“千年大喷发”）,其喷发产物——灰白色碱流质浮岩和喷发柱垮塌形成的火山碎屑流分布范围极广,除长白山区外,在朝鲜半岛和日本北部也有大量浮岩降落和堆积。根据野外较大范围的系统采样、镜下观察和测试分析,在天池火山千年大喷发产物的碱性长石晶屑中发现了两组颜色、形态、化学成分迥异的“火口组”和“圆池组”熔体包裹体,对揭示天池火山千年大喷发的成因具有重要意义。根据电子探针分析结果,“火口组”熔体包裹体成分为英安岩和粗面英安岩,寄主晶多为透长石;“圆池组”熔体包裹体成分为粗面英安岩和流纹岩,寄主晶为歪长石。相对“火口组”熔体包裹体,“圆池组”包裹体具有高SiO2、高H2O和高Cl含量的特点,化学成分也更为演化,可能是天池火山千年大喷发时岩浆结晶分异后期的产物。两组包裹体的存在为千年大喷发前的层状地壳岩浆房和成分并非单一提供了证据,它们可能是在同次大喷发的不同序列中喷出的。由于地幔岩浆注入地壳岩浆房,导致不同层位岩浆的扰动和混合作用,因挥发分出溶在岩浆房最顶部形成挥发分梯度和过饱和,最终触发了天池火山的千年大喷发,对当时的气候环境造成过较大影响。  相似文献   

地壳硅质岩浆演化的动力学机制SCIEI北大核心CSCD     

张吉衡  郑向雪  孙金凤  陈璟元  杨进辉 《岩石学报》2022,38(5):1481-1498

硅质岩浆的成因及演化机制研究是认识大陆地壳成分结构演化机制的关键途径。地壳硅质岩浆储库的基本性质及其演化的动力学过程是制约硅质岩浆演化及其多样性的根本原因,也是受到广泛关注的前沿和热点问题。本文总结了硅质岩浆储库的基本性质及其演化机制研究的相关进展,重点探讨了岩浆体系演化的动力学机制,即其物质成分及温度压力条件的动态演化过程,亦即岩浆储库在补给驱动下的存留、活化、分异、喷发过程。经由累积生长的方式形于地壳浅部的硅质岩浆储库以晶粥为主要赋存形式,具有较低的温度压力范围和高硅高结晶度高粘度的特征。岩浆储库的基本性质导致其自身不具有持续演化的能力,只有在基性岩浆补给的驱动下才能长时间存留分异或快速活化喷发。基性岩浆的补给及其携带的热及流体/挥发份深刻地改变了岩浆储库的物质成分及物理条件,是导致硅质岩浆分异演化或喷发的根本原因。本文还结合研究进展探讨了东南沿海地区中生代火山-侵入岩的成因演化机制及相关问题。  相似文献   

Variability in eruptive dynamics associated with caldera collapse: an example from two successive eruptions at Batur volcanic field,Bali, Indonesia     

O.?ReubiEmail author  I.?A.?Nicholls 《Bulletin of Volcanology》2004,66(2):134-148

Batur volcanic field (BVF) in Bali, Indonesia, underwent two successive caldera-forming eruptions, CI and CII (29,300 and 20,150 years b.p., respectively) that resulted in the deposition of dacitic ignimbrites. The respective ignimbrites show contrasted stratigraphies, exemplify the variability of dynamics associated with caldera-forming eruptions and provide insights into the possible controls exerted by caldera collapse mechanisms. The Ubud Ignimbrite is widespread and covers most of southern Bali. The deposits consist dominantly of pyroclastic flow with minor pumice fall deposits. The intra-caldera succession comprises three distinct, partially to densely welded cooling units separated by non-welded pyroclastic flow and fall deposits. The three cooling units consist of pyroclastic flow deposits only and together represent up to 16 distinct flow units, each including a thin, basal, lithic-rich breccia. This eruption was related to a 13.5×10 km caldera (CI) with a minimum collapsed volume of 62 km³. The floor of caldera CI is inferred to have a piecemeal geometry. The Ubud Ignimbrite is interpreted as the product of a relatively long-lasting, pulsating, collapsing fountain that underwent at least two time breaks. A stable column developed during the second time break. Discharge rate was high overall, but oscillatory, and increased toward the end of the eruption. These dynamics are thought to reflect sequential collapse of the CI structure. The Gunungkawi Ignimbrite is of more limited extent outside the source caldera and occurs only in central southern Bali. The Gunungkawi Ignimbrite proximal deposits consist of interbedded accretionary lapilli-bearing ash surge, ash fall, pumice lapilli fall and thin pyroclastic flow deposits, overlain by a thick and massive pyroclastic flow deposit with a thick basal lag breccia. The caldera (CII) is 7.5×6 km in size, with a minimum collapsed volume of 9 km³. The CII eruption included two distinct phases. During the first, eruption intensity was low to moderate and an unstable, essentially phreatomagmatic column developed. During the second phase, the onset of caldera collapse drastically increased the eruption intensity, resulting in column collapse. The caldera floor is believed to have subsided rapidly, producing a single, short-lived burst of high eruption intensity that resulted in the deposition of the uppermost massive pyroclastic flow.Editorial responsibility: T. Druitt  相似文献   

Complex changes in eruption dynamics during the 79 AD eruption of Vesuvius     

Lucia Gurioli  Bruce F. Houghton  Katherine V. Cashman  Raffaello Cioni 《Bulletin of Volcanology》2005,67(2):144-159

The 79 AD eruption of Vesuvius included 8 eruption units (EU1–8) and several complex transitions in eruptive style. This study focuses on two important transitions: (1) the abrupt change from white to gray pumice during the Plinian phase of the eruption (EU2 to EU3) and (2) the shift from sustained Plinian activity to the onset of caldera collapse (EU3 to EU4). Quantification of the textural features within individual pumice clasts reveals important changes in both the vesicles and groundmass crystals across each transition boundary. Clasts from the white Plinian fall deposit (EU2) present a simple story of decompression-driven crystallization followed by continuous bubble nucleation, growth and coalescence in the eruptive conduit. In contrast, pumices from the overlying gray Plinian fall deposit (EU3) are heterogeneous and show a wide range in both bubble and crystal textures. Extensive bubble growth, coalescence, and the onset of bubble collapse in pumices at the base of EU3 suggest that the early EU3 magma experienced protracted vesiculation that began during eruption of the EU2 phase and was modified by the physical effects of syn-eruptive mingling-mixing. Pumice clasts from higher in EU3 show higher bubble and crystal number densities and less evidence of bubble collapse, textural features that are interpreted to reflect more thorough mixing of two magmas by this stage of the eruption, with consequent increases in both vesiculation and crystallization. Pumice clasts from a short-lived, high column at the onset of caldera collapse (EU4) continue the trend of increasing crystallization (enhanced by mixing) but, unexpectedly, the melt in these clasts is more vesicular than in EU3 and, in the extreme, can be classified as reticulite. We suggest that the high melt vesicularity of EU4 reflects strong decompression following the partial collapse of the magma chamber.Editorial responsibility: D.B. Dingwell  相似文献   

Multiple levels of magma storage during the 1980 summer eruptions of Mount St. Helens, WA   总被引：1，自引：0，他引：1  

K. V. Cashman  S. M. McConnell 《Bulletin of Volcanology》2005,68(1):57-75

Transitions in eruptive style—explosive to effusive, sustained to pulsatory—are a common aspect of volcanic activity and present a major challenge to volcano monitoring efforts. A classic example of such transitions is provided by the activity of Mount St. Helens, WA, during 1980, where a climactic Plinian event on May 18 was followed by subplinian and vulcanian eruptions that became increasing pulsatory with time throughout the summer, finally progressing to episodic growth of a lava dome. Here we use variations in the textures, glass compositions and volatile contents of melt inclusions preserved in pyroclasts produced by the summer 1980 eruptions to determine conditions of magma ascent and storage that may have led to observed changes in eruptive activity. Five different pyroclast types identified in pyroclastic flow and fall deposits produced by eruptions in June 12, July 22 and August 7, 1980, provide evidence for multiple levels of magma storage prior to each event. Highly vesicular clasts have H₂O-rich (4.5–5.5 wt%) melt inclusions and lack groundmass microlites or hornblende reaction rims, characteristics that require magma storage at P≥160 MPa until shortly prior to eruption. All other clast types have groundmass microlites; P_H20 estimated from both H₂O-bearing melt inclusions and textural constraints provided by decompression experiments suggest pre-eruptive storage pressures of ∼75, 40, and 10 MPa. The distribution of pyroclast types within and between eruptive deposits can be used to place important constraints on eruption mechanisms. Fall and flow deposits from June 12, 1980, lack highly vesicular, microlite-free pyroclasts. This eruption was also preceded by a shallow intrusion on June 3, as evidenced by a seismic crisis and enhanced SO₂ emissions. Our constraints suggest that magma intruded to a depth of ≤4 km beneath the crater floor fed the June eruption. In contrast, eruptions of July and August, although shorter in duration and smaller in volume, erupted deep volatile-rich magma. If modeled as a simple cylinder, these data require a step-wise decrease in effective conduit diameter from 40–50 m in May and June to 8–12 m in July and August. The abundance of vesicular (intermediate to deep) clast types in July and August further suggests that this change was effected by narrowing the shallower part of the conduit, perhaps in response to solidification of intruded magma remaining in the shallow system after the June eruption. Eruptions from July to October were distinctly pulsatory, transitioning between subplinian and vulcanian in character. As originally suggested by Scandone and Malone (1985), a growing mismatch between the rate of magma ascent and magma disruption explains the increasingly pulsatory nature of the eruptions through time. Recent fragmentation experiments Spieler et al. (2004) suggest this mismatch may have been aided by the multiple levels at which magma was stored (and degassed) prior to these events.Editorial responsibility: J Stix  相似文献   

Ground deformation of Papandayan volcano before, during, and after the 2002 eruption as detected by GPS surveys     

Hasanuddin Z. Abidin  H. Andreas  M. Gamal  Ony K. Suganda  Irwan Meilano  M. Hendrasto  M. A. Kusuma  D. Darmawan  M. A. Purbawinata  A. D. Wirakusumah  F. Kimata 《GPS Solutions》2006,10(2):75-84

Papandayan is an A-type active volcano located in the southern part of Garut Regency, about 70 km southeast of Bandung, Indonesia. Its earliest recorded eruption, and the most violent and devastating outburst, occurred in 1772. The latest eruptions occurred in the period from 11 November–8 December 2002, and consisted of phreatic, freatomagmatic, and magmatic types of eruption. During the latest eruption period, GPS surveys were conducted at several points inside and around the crater in a radial mode, using the reference point located at the Papandayan observatory, about 10 km from the crater. At the points closest to the erupting craters, GPS displacements up to a few decimeters were detected, whereas at the points outside the crater, the displacements were at the centimeter level. The magnitude of displacements observed at each point also showed a temporal variation according to the eruption characteristics. The results show that deformation during eruption tends to be local, e.g. just around the crater. The pressure source is difficult to be properly modeled from GPS results, due to the limited GPS data available and differences in topography, geological structure, and/or rheology related to each GPS station.  相似文献